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TABLES
MINIMUM REQUIREMENTS FOR SUBMISSION OF SAMPLES
MATERIALS MNIMUM TESTING
REQUIREMENTS
MINIMUM QUANTITY/VOLUME OF
MATERIALS FOR EACH SAMPLE
SUBMITTED
1. Cement 1 sample per 2000 bags 10 kg
2. Asphaltic material 1 sample per 40T or 200 drums
5L
3. Aspahlt mix 1 sample per 130T 20 kg
4. Aggregates
a. coarse aggregate
b. fine aggregate
1 sample per 1,500 m3
70 kg
50 kg
5. Soil aggregates
a. Classification
b. Routinary tests
c. MDR test and CBR
1 sample per 1,500 m3
20 kg
50 kg
50 kg
6. Non – Reinforced Concrete Pipes 2 pipes min./0.5% of no. of pipes
2 pipes
7. Reinforced Concrete Pipes 1 sample per 50 pipes or 2% of # of
pipes
1 pipe (1 m length)
8.Steel pipe (galvanized) 1 sample per 500 lengths 2 pcs Of 100 mm long taken from both ends
w/ thread
9. Concrete hollow blocks (CHB)
a. strength
b. moisture content
1 sample per 10,000 units
3 units
3 units
10. Steel bar 1 sample per 10T 1 m
11. Steel sheet (galvanized) 1 sample per 100 sheets 3 pcs 60mm x 60mm
12. Wire strand 1 sample per 20T 2 m
13. Gabion 1m x 2m
14. Paints 1 sample per 100 cans 1 - 4L can
15. Joint – filler (pre – molded) 1 – 400mm x 400mm
16. Curing compound 1L
17. Concrete cylinder 1 sample per 75 m3 1 set (3 cylinders)
18. Concrete beam 1 sample per 75 m3 or 1 day
pouring 1 set (3 cylinders)
19. Concrete core 5 holes for every km/lane
20. Asphalt core 1 core for every 100m
21. Water
a. Chemical analysis
b. Sediment load analysis
500 ml
500 ml
22. Structural steel/sheet 1 sample per 50T Reduced section as prescribed
23. Hydrated lime 1 sample per 100T
2
COMPOSITION AND STRENGTH OF CONCRETE FOR USE IN STRUCTURE
Class of
concrete
Minimum
cement
content per
cu. m
kg (bags)
Maximum
water –
cement ratio
kg/kg
Consistency
range in
slump
mm (inch)
Designated
size of coarse
aggregate
square
opening –
std. mm
Minimum
compressive
strength of
150mm x
300mm
concrete
cylinder @ 28
days
MN/m2 (psi)
A 360 (9) 0.53 50 -100 (2 –
4)
37. 5 – 4.75
(1 ½ - No. 4) 20.7 (3000)
B 320 (8.5) 0.58 50 -100 (2 –
4)
50.0 – 4.75 (2
- No. 4) 16.5 (2400)
C 380 (9.5) 0.55 50 -100 (2 –
4)
12. 5 – 4.75
(½ - No. 4) 20.7 (3000)
P 440 (11) 0.49 100 max ( 4
max)
19.0 – 4.75
(3/4 - No. 4) 37. 7 (5000)
Seal 380 (9.5) 0.58 100 – 200 (4
– 8)
25.0 – 4.75 (1
- No. 4) 20.7 (3000)
PAYMENT ADJUSTMENT FOR PAVEMENT WITH DEFICIENCY IN STRENGTH
Deficiency in strength of concrete pavement
Percent (%)
Percent (%) of
contract price
Allowed
Less than 5 100
5 to less than 10 80
10 to less than 15 70
15 to less than 20 60
20 to less than 25 50
25 or more 0
PAYMENT ADJUSTMENT FOR PAVEMENT WITH DEFICIENCY IN THICKNESS
Deficiency in the
average thickness
per lot(mm)
Percent (%) of
contract price
per lot
0 – 5 100
6 – 10 95
11 – 15 85
16 – 20 70
21 – 25 50
more than 25 removed and replaced (no payment)
3
COMMON LABORATORY TESTS
Kind of material Type of test Test duration per sample
(min. # of days)
Cement Physical and chemical 8
Coarse aggregate Grading 3
Specific gravity 3
Absorption 3
Abrasion 1
Unit weight 1
Fine aggregate Grading 3
Specific gravity 3
Absorption 3
Unit weight 1
Soil aggregates mixture
(subbase, base and surfaces
courses
Grading 3
Liquid limit 3
Plastic limit 3
Compaction 3
CBR 7
Abrasion 1
Asphalt Physical 4
Paint Physical and chemical 4
Concrete cylinder Compressive 1
Concrete beam Flexural 1
Concrete core Cutting of sample 1
LIMITATIONS/VARIATIONS
ITEM
104 (Embankment)
ITEM
105 (Subgrade
preparation)
ITEM
200 Aggregate
Subbasecourse
1TEM
201 Aggregate
Base Course
ITEM
202 Crushed
Aggregare
ITEM
203 Lime stabilized
Road mix base
course
ITEM
300 Aggregate
Surface course
Abrasion loss 50%
max
50%
max
45%
max
45%
max
Plastic index 6% max
12%
max 6% max
6%
max
4% to
10%
4% to
9%
Liquid limit 30% max
35%
max
25%
max
25%
max
35%
max Permitted ±20mm ±10mm +15mm,
4
variation from
design
THICKNESS
OF LAYER
-5mm
Permitted
variation from
design LEVEL
OF SURFACE
+20mm,
-30mm
+10mm,
-20mm
-5mm, -
10mm
+15mm,
-5mm
Permitted
surface
irregularity
measured by 3-
m straight edge
30mm 20mm 5mm 5mm
Permitted
variation from
design cross fall
or camber
±0.5% ±0.3% ±0.2% +0.2%
Permitted
variation from
design
longitudinal
grade over 25m
length
±0.1% ±0.1% ±0.1% +0.1%
California
Bearing Ratio
25% min 80% min
80%
min 100% 80% min
DIMESION OF PILES
Length of pile Ø (1m from the butt) Minimum
tip Ø minimum maximum
less than 12m 300mm 450mm 200mm
12m to 18m 320mm 450mm 180mm
more than 18m 350mm 500mm 150mm
REMOVAL OF FORMS
Scope of work Minimum time Minimum % of design
strength
Centering under girders,
beams, frames or arches 14 days 80%
Floors slabs 14 days 70%
Walls 1 day 70%
Columns 2 days 70%
Sides of beams and all other
vertical surfaces 1 day 70%
SIEVE SIZES
NO. 200 0.075mm NO. 20 0.840mm
NO. 100 0.150mm NO. 16 1.180mm
NO. 60 0.300mm NO. 12 1.700mm
NO.50 0.250mm NO. 10 2.000mm
NO. 40 0.425mm NO. 8 2.360mm
NO. 30 0.600mm NO. 4 4.750mm
5
DETAILS OF WELDS
Size of fillet weld Maximum thickness of part
5mm 13mm
6mm 19mm
8mm 32mm
10mm 51mm
13mm 152mm
16mm 152mm and above
MINIMUM LAP FOR SPLICING
GRADE 40 GRADE 60
Tension 24 times bar Ø 36 times bar Ø
Compression 20 times bar Ø 24 times bar Ø
MINERAL FILLER SHALL BE GRADE WITH IN THE FF. LIMITS (703-A)
Sieve size Mass % passing
NO. 30 100
NO. 50 95 – 100
NO. 200 70 – 100
HYDRATED LIME SHALL CONFORM TO THE FF. REQUIREMENTS (701)
Sieve size Mass % passing
NO. 20 100
NO. 200 85 – 100
MINIMUM WEIGHT OF SAMPLE FOR MOISTURE CONTENT
Sieve No. (passing) Weight
NO. 40 25 grams
NO. 10 50 grams
NO. 4 200 grams
½” 300 grams
1” 500 grams
2” 1000 grams
6
REVIEW
QUESTIONS
1. What is the sample for compressive strength determination of a structural concrete?
Answer: concrete cylinder sample
2. What is the test to determine the consistency of concrete?
Answer: Slump test
3. What is the length required for RSB sample for quality test?
Answer: 1.0 m/10,000kg/size/shipment
4. How many samples should be taken for every 75 cu.m fresh concrete?
Answer: 1 set consist of 3-pcs sample
5. What is the required size of test specimen for G.I. sheets?
Answer: 3 pcs-60mm x 60mm in 1 sht/100shts
6. What kind of paint that has a reflectance or beads?
7
Answer: Reflectorized paint
7. What is that construction material that has a property of being a dark brown to black cementitious
material in which the predominating substance is bitumen?
Answer: asphalt
8. For how long or how many hours shall a bituminous prime coat be left undisturbed?
Answer: 24 hours
9. What is the rate of application of bituminous tack coat?
Answer: 0.2 to 0.7 L/sq. m
10. What is the penetration grade of blown asphalt?
Answer: 0 to 30 penetration grade
11. What kind of sample is taken for flexural test?
Answer: concrete beam sample
12. What are the tests needed for the 2.650 cu.m Item 201 (Aggregate Base Course)?
Answer: CBR, abrasion, GPCD
13. How many grading tests are required for a 3,200 cu.m selected borrow topping (Item 104)?
Answer: 3 grading tests
14. As a materials Engineer, what will you recommend if you find out that the materials to be used as
Item 200 if finer than the required materials?
Answer: blend Item 200 with coarser materials
15. What is the standard specification for LL and PI of Item 201?
Answer: maximum of 25% and maximum of 6% respectively
16. What is the CBR requirement for Item 201?
Answer: 80% maximum
17. What asphalt is used for sealing weaken plane joint of concrete pavement?
Answer: Blown Asphalt
18. What is Item 311 of the DPWH Specification (Blue Book)?
Answer: Portland Cement Concrete Pavement
19. What is the machine used for abrasion test?
Answer: Los Angeles Abrasion Machine
20. How to determine the degree of compaction of Items 104, 200, & 201?
Answer: by Field Density Test
21. What is the formula in obtaining the value of PI?
Answer: Liquid Limit minus Plastic Limit
22. What are the other terms for sieve analysis?
Answer: Grading Test, Particle Size Distribution Test, Mechanical Analysis
8
23. What is the degree of compaction of the soil if the wet density is 2,200 kg/m3, with an actual
moisture content of 10.2% and a maximum dry density of 1,960 kg/m3?
Answer: 101.86%
24. How many concrete cores shall be taken for one (1) kilometer concrete pavement?
Answer: 5 holes/km/lane
25. What is the moisture content of the soil having an original weight of 162.5 grams and an oven –
dried weight of 138.2 grams?
Answer: 17.58%
26. If the group index of a soil is high, what indication does it mean?
Answer: the soil is clayey
27. As a Materials Engineer, how can you determine that the sample placed in the oven is already oven –
dried?
Answer: if the sample reaches its constant weight
28. In oven drying a sample for test, what temperature shall be maintained?
Answer: 110 ± 5°C
29. Why is it that cooling an oven dried sample before weighing is advisable?
Answer: because it can affect its weight
30. What is the difference between hygroscopic moisture content from natural moisture content?
Answer: HYGROSCOPIC MOISTURE CONTENT is the moisture content of an air – dried
sample while NATURAL MOISTURE CONTENT is the moisture content of the original
sample from the field.
31. For how many bags of cement does a 10 kgs sample represents?
Answer: 2000 bags
32. For 15, 000 kgs RSB, how many samples shall be submitted for Quality Test?
Answer: 2 pcs – 1 m sample
33. An admixture is being introduced to the fresh concrete mixture for heavily reinforced concrete
structure using a pumpcrete to pump out the fresh concrete mix, what admixture should it be?
Answer: Superplasticizer
34. What is the use of blown asphalt?
Answer: as joint filler and water proofing
35. What asphalt is commonly known as hot asphalt or penetration grade asphalt?
Answer: Asphalt Cement
36. How many days does the sample for Immersion – Compression Test be soaked in water?
Answer: 4 days @ 50°C
37. If ductility test is for asphalt, _____ is for cement?
Answer: Magnesium Oxide, Insoluble Residue, Loss on Ignition
9
38. Paint is composed of _____
Answer: 35% vehicle, 50% pigment, 15% beads
39. What is the size of tamping rod used in tamping concrete sample?
Answer: 16 mm Ø and 610 mm long with hemispherical tip
40. What is the temperature to be maintained when curing sample after its initial curing?
Answer: 23°C ± 1.7°C
41. Concrete cylinders are cured and ready for test. Temperature between 63°F to 85°F are permitted for
a period not to exceed _____ hours immediately prior to test if free moisture is maintained on the
surface of the specimen at all times.
Answer: three (3)
42. The molds of specimen not to be transported shall be removed after initial curing of _____ hours and
should be cured to the standard curing temperature of 73.4 °F ± 3°F
Answer: Twenty – four (24)
43. High plasticity index means _____ of a soil?
Answer: high degree of compressibility
44. Sample to be used for liquid limit and plastic limit tests should pass to what sieve?
Answer: No. 40 (0.425 mm)
45. What compaction rammer shall used if the specs given for Moisture – Density Relation Test (MDR)
is T – 180?
Answer: 4.54 kg with 457 mm drop
46. A bean mold measuring 6” x 6” x 20 is to be used for sampling concrete, how many blows/tamps per
layer shall be applied?
Answer: 60 blows/layer
47. If asphalt mix having a weight of 3,020g and an aggregate weighing 2,865.98g, what is the % asphalt
by weight of mix?
Answer: 5.10%
48. What is the material used for Bituminous Prime Coat?
Answer: Cut – back asphalt
49. In Item 303, application of cover aggregates shall be evenly spread over the surface at the rate of
approximately _____?
Answer: 0.004 to 0.007 m3/m
2
50. Applying the tolerance of 0.4% for asphalt content to your answer in prob. 47, what is the acceptable
range of asphalt content?
Answer: 4.7% to 5.5%
51. An embankment having a PI of 30%, LL of 40% and GI of 0, what is the degree of compaction for
this kind of soil?
Answer: 95% degree of compaction
10
52. The minimum cement factor for concrete Class “A” is 9 bags/cu.m, how about for concrete Class
“B”?
Answer: 8 bags/cu.m
53. Quality control testing in a DPWH project is the responsibility of the_____?
Answer: Contractor
54. As Materials Engineer, when is the right time to start sampling and testing aggregates?
Answer: Once the source is identified
55. The minimum compressive strength for concrete Class “P” is 5,000 psi, what is the minimum
compressive strength for concrete Class “C”?
Answer: 3,000 psi
56. The volume of concrete mixer per batch shall not exceed the mixer’s nominal capacity in cu.m as
shown on the manufacturer’s standard plate on the mixer, except that an overload up to _____
percent above the mixer’s nominal capacity may be permitted provided concrete test data for
strength, segregation, and uniform consistency are satisfactory, and provided that no spillage of
concrete takes place.
Answer: Ten (10)
57. Where do we take additional cores when the measurement of any core taken from pavement is
deficient in thickness by more than 25 mm?
Answer: at no less than 5 meter intervals parallel to the centerline in each direction from the
affected location
58. Under what climatic condition do we use lower penetration grade or hard asphalt?
Answer: hot climate (cold climate – higher penetration grade or soft asphalt)
59. What is the basis for the acceptance or rejection of any construction material?
Answer: Materials test results/reports
60. Penetration test is for asphalt: cement is to _____?
Answer: consistency
61. Slump test is a very important test in fresh concrete to determine _____?
Answer: consistency of concrete
62. How many samples should be taken for an asphalt mix for each full day’s operation?
Answer: at least one but not to exceed three samples
63. The thickness of asphalt core using a caliper is based on how many measurements?
Answer: four (4)
64. The thickness of concrete core using a caliper is based on how many measurements?
Answer: nine (9)
65. Failed samples do not necessarily mean that the structure it represents is defective, why?
Answer: may be the sampling is incorrect
66. The specification calls for a 1: 2:4 concrete mix. In a one bagger mixer, which of the following
amount of water is most likely required for the mix?
Answer: 20 liters
11
67. The spot test on asphalt is used to determine ______.
Answer: overheating during the process of manufacture
68. How many samples shall be submitted for test if 315 pails of flat wall enamel paint are to be used in
the project?
Answer: four (4) pails
69. Aggregate Sub – base course has a volume of 5, 000 cu.m and to be laid in a 15cm compacted depth.
How many samples shall be submitted for CBR test and for sieve analysis?
Answer: 2 samples for CBR and 17 samples for sieve analysis
70. How many samples shall be submitted for quality test if 60 tons of Bituminous Prime Coat is to be
used in the project?
Answer: Two (2) samples
71. How many compaction tests shall be conducted for Item 201 having a volume of 8,250 cu.m?
Answer: Six (6) compaction tests
72. What composed of Materials Quality Control Monthly Reports?
Answer: Summary of field tests and status of test
73. What is the required mixing of mortar for Item 505 (Stone Masonry)?
Answer: 1 part cement and 2 parts sand by volume with sufficient water
74. What is the required mixing of mortar for Item 500 (Pipe Culverts and Storm Drains)?
Answer: 1 part cement and 2 parts sand by volume with sufficient water
75. Before the project starts, the materials Engineer or the technician must have a program on how many
samples for each item of work should be tested based on the minimum testing requirements. What
program or report is this?
Answer: Quality Control Program
76. If sample splitter is not available for use in reducing samples for test, what is the alternative way of
reducing sample for testing size?
Answer: apply quartering method and get two opposite sides as sample
77. The road will not be opened to traffic until test specimens molded and cured have attained the
minimum strength requirements. If such tests are not conducted prior to the specified age the
pavement shall not be operated to traffic until _____ days after the concrete was placed.
Answer: Fourteen (14)
78. As the work progresses, the Materials Engineer should know how many sample has been submitted
and tested and how many samples are to be submitted, in other words the ME must refer to what
report so that he/she may be updated on the balance and on file quality test of the construction
materials being used in the project?
Answer: Status of Test
79. It is the minimum moisture content at which the soil can be molded without breaking or crumbling
up to 1/8” (3.2 mm).
Answer: Plastic Limit
12
80. The _____ is expressed as the moisture content corresponding to 25 blows.
Answer: Liquid Limit
81. The concrete has been tested for consistency by the use of a slump cone with base and tamping rod.
After the test, the height of concrete measured is 178 mm. what is the slump of the concrete?
Answer: 127 mm
82. What is the rate of revolution per minute of an abrasion Machine used for testing the mass percent of
wear?
Answer: 30 – 33 rpm
83. If the design of concrete mix has the following corrected batch weights: cement = 40 kgs, fine
aggregates = 65 kgs, coarse aggregate = 115 kgs, and water = 15 liters. What is your actual batch
weights for 1 cu.m Class “A” concrete?
Answer: 360 bags of cement; 585 kgs of fine aggregates; 1035 kgs coarse aggregates; 130 liters
water
84. After the soil has been tested in an Abrasion Machine, the mass % of wear computed is equal to
21%. If this material is for Item 201, does it pass the DPWH specs?
Answer: Yes, because the specs is 50% maximum
85. Quality Control Assurance Report should be submitted every _____?
Answer: week
86. One of the duties of Materials Engineer is to see to it that all the construction materials be tested:
Answer: before it is incorporated into work
87. What is the maximum depth or roadway embankment per horizontal layer in loose measurement?
Answer: 200 mm loose measurement
88. Why is it that 6 samples are needed for quality test of concrete masonry?
Answer: 3 samples for compressive strength and 3 samples for absorption
89. Sample submitted for test should have a tag bearing the name of the project, the quantity represented,
kind of sample, original source, who sampled and who submitted it, the date sampled and date
submitted and etc. What is the common name of that tag for you as Materials Engineer?
Answer: Sample Card
90. If course aggregate like embankment is to be placed in layers, how many layers should a 40 cm thick
Aggregate Base Course is placed?
Answer: Three (3)
91. The ME should always be alert of his schedule with regards to the number of days of a quality test
that takes place. Since not all construction materials can be tested just for a day or even a week so,
what is the lead time should he consider for a quality test of a cement sample?
Answer: One (1) month
92. CBR Sample for test has been compacted but it should be soaked for how many days before testing?
Answer: Four (4)
93. If sieve analysis and plasticity test are used for Soil Classification, what test that its result be used in
field density test?
13
Answer: Compaction Test or Moisture Density Relation Test
94. Heavy rains occur the night before prior to your scheduled field density test, are you going to pursue
your schedule? Why?
Answer: No, because the moisture content is high and can affect the result
95. Checking the gradation of composite aggregates and asphalt content of asphalt mix can be done by
what test?
Answer: Extraction Test
96. What is the device used in testing for liquid limit test?
Answer: liquid limit device with grooving tool
97. What apparatus is used in plastic limit test?
Answer: glass plate
98. How long does a vibrator be inserted in a concrete mix?
Answer: not to exceed 15 seconds at 50 – 60 cm interval
99. Along the slope of high embankment _____ is provided as an erosion control measures and also to
improve the stability of the slope.
Answer: Berm
100. In soil and sub – surface explorations for flood control design of foundation condition, a soil sample
was taken for field and laboratory tests. The test required for soil was taken, except
Answer: specific gravity, abrasion, water content, Atterberg Limits, gradation, compaction, relative
density
101. Structure crossing above such covered underground drainage conduit shall be laid at least _____
above the top of the conduit.
Answer: 1.0 m, 0.5 m, 1.5 m, 2.0 m
102. Class of stones for riprap ranging from 30 kgs to a maximum of 70 kgs with at least 50% of the
stones weighing more than 50 kgs.
Answer: Class B
103. Class of stones for riprap ranging from 15 kgs to a maximum of 25 kgs with at least 50% of the
stones weighing more than 20 kgs.
Answer: Class A
104. Class of stones for riprap ranging from 60 kgs to a maximum of 100 kgs with at least 50% of the
stones weighing more than 80 kgs.
Answer: Class C
105. Class of stones for riprap ranging from 100 kgs to a maximum of 200 kgs with at least 50% of the
stones weighing more than 1500 kgs.
Answer: Class D
106. The maximum size of stone for stone masonry.
Answer: 150 mm
107. The maximum size of aggregate for item 300.
Answer: 1 inch
14
108. Required maximum liquid limit for Item 300.
Answer: 35%
109. Required plasticity index range on Item 300.
Answer: 4% to 9%
110. Range of sand size.
Answer: 2.0 mm to 0.050 mm Ø
111. The ratio of the volume of voids to volume of solids
Answer: void ratio
112. The ratio of the weight of water to the weight of solids
Answer: moisture content
113. Significance of grading test are, except
Answer: Gives particle size distribution, measures permeability, capillarity, measures the potential
cohesion of soil
114. Significance of plasticity index are, except
Answer: indicates compressibility, permeability, indicates the clay fraction of a binder material,
measures the shearing resistance of soil
115. Properties of concrete are, except
Answer: workability, strength, durability, cracking
116. In roadway construction test on sub grade, the following will determine the economical thickness,
except
Answer: embankment, base, surfacing, sub-base
117. The relative consistency of a cohesive soil in natural state.
Answer: Liquidity Index
118. In Atterberg limit, the following are determined, except
Answer: shrinkage limit, liquid limit, plastic limit, group index
119. Minimum time for removal of forms and false works for centering under girders, beam, frames and
arches.
Answer: 14 days (minimum % of design strength – 80%)
120. Minimum time for removal of forms and false works for floor slabs.
Answer: 14 days (minimum % of design strength – 70%)
121. Minimum time for removal of forms and false works for walls.
Answer: 1 day (minimum % of design strength – 70%)
122. Minimum time for removal of forms and false works for columns.
Answer: 2 days (minimum % of design strength – 70%)
123. Minimum time for removal of forms and false works for side of beams and all other vertical
surfaces.
Answer: 1 day (minimum % of design strength – 70%)
15
124. Amass of solid reinforced concrete cast around the head of a group of piles to ensure that act as a
unit to support the imposed load
Answer: Pile cap
125: An embankment shall be compacted layer by layer.
Answer: 150 mm
126. Class of concrete deposited in water.
Answer: Class Seal
127. Class of concrete used in all superstructures and heavily reinforced substructures. The important
parts of the structure included are slabs, beams, girders, columns, arch ribs, box culverts, reinforced
abutments, retaining walls, and reinforced footings.
Answer: Class A
128. Class of concrete used in footings, pedestal, massive pier shafts, pipe bedding and gravity walls,
unreinforced or w/ only a small amount of reinforcement.
Answer: Class B
129. Class of concrete used in thin reinforced sections, railings, pre-cast piles, cribbing, and for filler in
steel grid floors.
Answer: Class C
130. Class of concrete used in pre – stressed concrete structures and members.
Answer: Class P
131. Height of dropping concrete to the point of deposit
Answer: 1.50 m
132. Reflectorized Thermoplastic Pavement Markings
Answer: Item 612
133. Permitted variation from the design thickness of layer for Item 300
Answer: + 15 mm and – 5 mm
134. Item 310 shall have a mass percent of air voids with range of _____
Answer: 3% to 5 %
135. Dowel bars for PCCP shall be _____
Answer: plain bars
136. Concrete beam sample when tested by Third – Point Method shall have a flexural strength of _____
when tested in 14 days.
Answer: 3.80 MPa
137. When the required thickness of Item 200 is more than 150 mm, the aggregate sub – base shall
spread and compacted in ____
` Answer: two or more layers
16
138. Item 202 shall have a minimum soaked CBR value of _____
Answer: 80%
139. Permitted variation from design thickness of layer for Item 201.
Answer: ± 10 mm
140. Sieve designation standard (in mm) for 0.425 mm to alternate US standard
Answer: No. 40
141. If slag is used as course aggregate for Item 311, the minimum density is _____
Answer: 1,120 kg/m3
142. Minimum price allowed of contract for deficiency in strength of concrete specimens for PCCP
which 10% to less than 15%
Answer: 70%
143. This joint is also called cold joint. It is constructed when there is an interruption of more than 30
minutes in the concreting operation
Answer: Transverse Construction Joint
144. Minimum variation of the surface from the testing edge of the straight edge between contacts with
the surface in Item 310
Answer: 6.0 mm
145. Portland Cement Treated Plant Mix Base Course after the completion of the final rolling, the
surface will be treated with bituminous curing seal, how much is the rate of application?
Answer: 0.5 L/m2 to 1.0 L/m
2
146. In Item 201, the volume required in the project is 10,000 cu.m. The required number of CBR test is
_____
Answer: four (4)
147. Slump test of concrete determines the following, except
Answer: workability, fluidity, consistency, job density
148. The significance of liquid limit are the ff., except
Answer: measures the shearing resistance of soil, measures the potential cohesion of soil, fineness
and shape of grain, Atterberg limits
149. In soil classification, 35% or less passing No. 200 sieve are the ff., except
Answer: A-1, A-2, A-3, A-4
150. To evaluate the performance quality of a soil as a highway subgrade material
Answer: Group Index
151. If the paving of concrete pavement will be done at the rate 200 ln.m, half width per paving day,
how many sets of concrete beam samples shall be required. Given: A = 115,000 sq.m, width = 6.50
m, thickness = 230 mm
Answer: 353 sets
152. The required liquid limit for selected borrow toppings
17
Answer: 30%
153. The maximum plastic limit for selected borrow toppings
Answer: 6%
154. Soil is considered unsuitable material when the liquid limit and plastic limit exceeds
Answer: 80% and 55% respectively
155. Soil is considered unsuitable when the material density is
Answer: 800 kg/cu.m or lower
156. The plasticity index is determined in accordance with
Answer: AASHTO T 90
157. The liquid limit is determined in accordance with
Answer: AASHTO T 89
158. The required compaction of embankment, layer by layer
Answer: 95%
159. The minimum compaction trial of embankment
Answer: 10 m wide by 50 m long
160. At least how many in – situ density tests should be carried out for each 500 m2
of each layer of
compacted fill?
Answer: three (3)
161. Maximum plasticity index for Item 200
Answer: 12%
162. Maximum liquid limit for Item 200
Answer: 35%
163. Maximum size of grading requirement for Item 200
Answer: 2”
164. The Los Angeles Abrasion Test for aggregate sub-base course is determined in accordance with
Answer: AASHTO T 96
165. The required abrasion loss for Item 200
Answer: 50%
166. The minimum CBR required for Item 200
Answer: 25%
167. The required soaked CBR for aggregate sub-base course is determined by
Answer: AASHTO T 193
168. Minimum required percent compaction of each layer of aggregate sub-base course
Answer: 100%
18
169. In – place density determination of aggregate sub-base course material shall be made in accordance
with
Answer: AASHTO T 191
170. In some areas where the conventional base course materials are scarce or non – available, the use
_____ allowable percent weathered limestone (anapog) blended with crushed stones or gravel.
Answer: 40% (60% - crushed stones or gravel)
171. Maximum size of aggregate for base course material under grading B
Answer: 1 ½ inch
172. Maximum required percent abrasion loss for Item 202
Answer: 45%
173. Maximum required mass percent shall have at least one (1) fractured face of Item 202
Answer: 50%
174. Minimum required soaked CBR for Item 202
Answer: 80%
175. Maximum size of aggregate for Item 202 under grading A
Answer: 1 ½ inch
176. Maximum size of aggregate for Item 201 under grading A
Answer: 2”
177. Maximum size of aggregate for Item 202 under grading B
Answer: 1 inch
178. This item consists of a foundation for surface course composed of soil aggregate, lime, water in
proper proportion, road – mixed and constructed on a prepared subgrade/subbase.
Answer: Lime Stabilized Road Mix Base Course (Item 203)
179. The required plasticity index for Item 203
Answer: 4% to 10%
180. Maximum required mass percent of wear for the aggregate on Item 203
Answer: 50%
181. Maximum size of aggregate for Item 203 under grading A and B
Answer: 2”
182. Item number for water?
Answer: Item 714
183. In Item 203, how much is the required mass percent of lime to be added to the soil aggregate?
Answer: 3% to 12%
184. Minimum soaked CBR for Item 203
Answer: 100%
185. Required percent compaction for Item 203
19
Answer: 100%
186. Equipment to be used for initial rolling
Answer: Pneumatic tire roller
187. Equipment to be used for final rolling
Answer: 3 – wheel tandem type steel wheel roller
188. The test on asphalt cement consisting of heating the asphalt in an open cup and passing a small test
flame
Answer: flash point
189. It is a manually – operated device for deriving a measurement of roughness from the surface profile
which may be expressed in terms of International Roughness Index.
Answer: Merlin Road Roughness Measuring Device
190. It is used for the rapid in – situ measurement of the structural properties of existing pavement with
unbound granular properties.
Answer: Dynamic Cone Penetrometer
191. What is the thinnest cut – back asphalt?
Answer: MC – 3000
192. In the construction of bridges projects, what is the method used to determine the casting length of
the regular piles?
Answer: Test Pitting
193. It is an equipment which is used to measure differential deflection between joints of a concrete
pavement, to determine the modulus of the existing slabs for use in the design of an overlay, and to
determine the remaining life of existing pavement.
Answer: Falling Weight Deflectometer
194. What is the equipment used to pinpoint rebars, conduits, pipes, nails and other metals embedded in
concrete before cutting or drilling?
Answer: Rebar Locator
195. What is the instrument or equipment used to measure for surface test of concrete and asphalt
pavements as soon as he concrete has hardened sufficiently or as soon as the asphalt mix has been
initially compacted?
Answer: 3 – meter straight edge
196. What is the latest state of the art equipment consuming radioactive material which is commonly
used in the compaction control of earth and asphalt road construction and in the measurement of
moisture content?
Answer: Nuclear Density Gauge
197. It is an instrument used to measure pavement deflections resulting from vehicle wheel loadings.
The results of the elastic deformation tests are used to evaluate the structural condition of roads, and
to help in the design of road strengthening measures and road capacity improvement.
Answer: Benkelman Beam and Deflection Logger
20
198. What is the instrument that is used for examining the quality of rigid materials such as rocks and
concrete? This instrument is a non – destructive portable instrument with dimensions of 110 mm x
180 mm x 160 mm and its main uses includes the determination of concrete strength (either in – situ
or pre – cast),also to determine the presence of voids, cracks and other imperfections.
Answer: Pundit Ultrasonic Concrete Tester
199. Soil stabilizing agent
Answer: Lime – for silty and clayey soil
Cement – fro sandy soil
200. Water content at which soil passes from plastic to liquid state.
Answer: LIQUID LIMIT
201. Water content at which soil passes from semi – solid to plastic state.
Answer: PLASTIC LIMIT
202. Water content at which soil passes from solid to semi – solid.
Answer: SHRINKAGE LIMIT
203. Steel bars placed along longitudinal joints to hold the adjoining slabs together are called _____
Answer: tie bars
204. The concrete pavement surface shows high spots of 15 mm in a 3 – m straight edge. The concrete in
the area represented by these high spots _____
Answer: shall be removed and replaced (but if high spots being noted exceeds 3 mm but not
exceeding 12 mm, it shall be ground down only.
205. The calibration of the Universal testing machine is conducted _____
Answer: Once a year
206. What is the sampling requirement of bituminous mixture?
Answer: 1 sample per 130 tonnes
207. What is the depth of the thermometer inserted in the bituminous mixture?
Answer: 2”
208. In the design of bituminous mix, the design criteria for stability under the Marshall Stability
Method for heavy traffic is ____
Answer: 1800 lbs
209. The stability criteria of the Marshall Stability Method is the maximum load resistance that a
specimen will develop at _____
Answer: 60°
210. Bituminous mix specimens are compacted at how many blows at each end for a heavy traffic design
under the Marshall Stability Method?
Answer: 75 blows
211. In a penetration test, if the penetration is 9. What is the grade of the asphalt?
Answer: 85 – 100
21
212. In case of scarcity or non – availability of Type I Portland cement, what type of pozzolan shall be
used?
Answer: Portland Pozzolan Cement Type 1P
213. The required flexural strength of concrete beam sample of Item 311 when tested by the midpoint
method.
Answer: 4.50 MPa
214. The required forms to be used in concrete pavement are _____
Answer: Steel forms of an approved section
215. Sowing of the weakened plane joints shall be done usually at _____
Answer: Within 24 hours
216. Removal of forms of concrete pavement
Answer: 24 hours
217. The required slump of concrete using slip – form method of paving is _____
Answer: 1 ½ inches
218. Deficiency in strength of concrete specimen wherein no payment of contract price allowed is _____
Answer: 25% or more
219. What is the length of a lot of pavement when a single traffic lane is poured?
Answer: 1,000 ln.m
220. What is the length of a lot of pavement when two lanes lane are poured concurrently?
Answer: 500 ln. m
221. What is the required size of concrete beam sample?
Answer: 150 mm x 150 mm x 525 mm
222. What is the required number of set of concrete beam specimens to be taken from each 330 sq. m of
pavement of fraction thereof placed each day?
Answer: 1 set
223. What is the required compressive strength that concrete piles be moved?
Answer: 80% of the designed 28 – day compressive strength
224. The required circular pin diameter used to bend 10 – 20 mm Ø reinforcing steel.
Answer: 6d (20 mm – 25 mm Ø = 8d: 28 mm Ø and above = 10d)
225. The mixing speed of the transit mixer during batching.
Answer: 4 to 6 rpm
226. What is the slump of concrete Class A deposited in water?
Answer: 10 to 20 cm
227. This item shall consist of preparing and treating an aggregate base course preparatory to the
construction of a bituminous surface course.
Answer: Prime Coat
22
228. What item no. is Bituminous Surface Treatment?
Answer: Item 304
229. What is the required tolerance for bituminous material in job – mix formula for Item 310?
Answer: ± 0.4%
230. This item consists of an application of bituminous material with or without the application of
aggregate on existing bituminous surface?
Answer: Seal Coat
231. Job – mix tolerance for temperature in the mixture for Item 310.
Answer: ± 10°C
232. What is the size of the sample in Item 310 taken for each full day’s operation?
Answer: 150 mm x 150 mm or 100 mm Ø
233. What is the required temperature of mix in item 310 when placed?
Answer: 107°C
234. The required speed in rolling in Item 310.
Answer: 5 kph
235. It is the resulting difference in elevation across a joint or crack.
Answer: faulting
236. In core specimen asphalt mix thickness determination, it shall have a diameter of at least ______
Answer: 100 mm
237. In batching concrete mix, the accuracy of cement content shall be _____
Answer: ± 1.0 mass %
238. Minimum thickness measured perpendicular to the slope using Class D stones for riprap.
Answer: 800 mm (Class A – 300 mm; Class B – 500 mm; Class C – 600 mm)
239. This item shall consist of preparing and bearing an existing bituminous or cement concrete surface
with bituminous materials preparatory to the construction of bituminous surface course.
Answer: Tack Coat
240. What is the rate of application of bituminous seal coat using asphalt cement?
Answer: 0.9 to 1.8 lit/m2
241. What is the rate of application of bituminous seal coat using cut – back asphalt?
Answer: 1.5 to 3.0 lit/m2
242. What is the maximum tolerance of the variation of the surface of Item 310 from the testing edge of
the straight edge between any two contacts with the surface?
Answer: 6 mm
243. What is the minimum dry compressive of Item 310?
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Answer: 1.40 MPa
244. What is the required Index of Retained Strength of Item 310 when tested by AASHTO T 65?
Answer: 70% minimum
245. Job – mix tolerance in Item 310 for grading, passing No. 4 and larger sieve.
Answer: ±7
246. Job – mix tolerance in Item 310 for grading, passing No 8 to No. 100 (inclusive).
Answer: ±4
247. .Job – mix tolerance in Item 310 for grading, passing No. 200 sieve.
Answer: ±2
248. The property of asphalt mix to resist deformation from imposed load.
Answer: stability
249. The property of asphalt mix to resist the detrimental effects of air, water, temperature and traffic.
Answer: durability
250. The property of asphalt mix to withstand repeated flexing caused by the passage of wheel loads.
Answer: fatigue resistance
251. The property of asphalt mix to bend slightly without cracking and to conform to gradual settlements
and moments of the base and subgrade.
Answer: flexibility
252. The range of aggregates composition in Item 310.
Answer: 92% to 95%
253. What is the test on asphalt in order to determine the effect of water on the cohesion of the mix?
Answer: Immersion – Compression Test
254. In temperate countries like the Philippines, what is the most commonly used grade of asphalt
cement?
Answer: 60 – 70 and 85 – 100
255. To determine the thickness _____ of asphalt, Immersion – Compression Test is performed.
Answer: stability
256. Percent air voids will _____ as percent asphalt increases in Marshall Stability.
Answer: decrease
257. To determine the temperature of delivered asphalt mix, what apparatus is used?
Answer: armored thermometer
258. Peat and muck soils are considered as:
Answer: highly organic soils
259. Why is it that a trial section is conducted in sub – base or base course construction?
24
Answer: to check the suitability of materials, efficiency of the equipment used and the
construction method.
260. What does it mean when there is bleeding in a newly paved asphalt road?
Answer: excessive asphalt content
261. A good subgrade soil should have the following:
Answer: low liquid limit and low plastic limit
262. Concrete samples may be tested at an earlier stage in order to _____
Answer: determine the trend of its strength development
263. What is the test criterion for reinforced concrete pipe tested in a three – edge bearing test machine?
Answer: 0.3 mm crack
264. In testing concrete cylinder sample, the applied load should be continuous without shock at a
constant rate within the range of _____
Answer: 20 to 50 psi/second (compression); 125 – 175 psi/second (flexural)
265. Cement which has been in storage for a long period of time and that there is already doubt as to its
quality should:
Answer: be retested prior to use
266. It is a process of improving the properties of soil to make it more suitable for a particular purpose.
Answer: Stabilization
267. Two tests are done in one lot sample. The test differs from each other, third test is taken. What will
be this test?
Answer: referee test
268. If no beam sample taken to determine the strength of concrete pavement, is it allowed in DPWH
specs to use core samples to determine the strength. What is the required compressive strength?
Answer: Yes, 3,500 psi at 14 days
269. Tact coat must be at what condition prior to the application of asphalt mix?
Answer: tacky
270. The use of sea water in reinforced concrete may _____
Answer: induce risk of corrosion in reinforcing steel
271. Subgrade having a CBR value of 2% or less is considered _____
Answer: weak subgrade
272. Subgrade having a CBR value of 15% or more is considered _____
Answer: very stable
273. Subgrade other than those defined in the two above categories is considered ___
Answer: normal
274. What are the three (3) major groups of soil?
Answer: granular soil, fine grained soil, organic soil
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275. What is the significance of field density test?
Answer: to determine the degree of compaction of soil. It is also a control test in embankment
construction to ensure adequate compaction.
276. Weighing hot sample is not advisable because it affects the accuracy of the result. True or false?
Answer: true
277. How to prepare or to come up with an air – dried sample?
Answer: air dry the sample under the heat of the sun
278. If it is impossible to air – dry the sample under the heat of the sun, what alternative should be used?
Answer: oven – dry the sample @ 60°C
279. Sample for compaction test should pass to what sieve size?
Answer: Method A & B – use sample passing No. 4
Method C & D – use sample passing ¾ inch
280. What is the difference between T – 99 and T – 180 compaction test method?
Answer: T – 99 uses 2.5kg (5.5lbs) rammer with a 12” drop while T – 180 uses 4.54 kg (10lbs)
rammer with an 18” drop.
281. What is particle size analysis?
Answer: It is the determination of particle size distribution in soils by sieve, hydrometer or a
combined analysis
282. What kind of water shall be used in laboratory test especially if it deals with chemicals?
Answer: distilled water
283. Liquid limit brass cup w/ sample is raised and allowed to drop sharply on the base through a height
of _____?
Answer: 10 mm
284. How many rotations per second will the crank of a liquid limit be rotated?
Answer: 2 rps
285. In doing a plastic limit test, to what Ø will the soil thread begin to break?
Answer: 3.2 mm (1/8”)
286. What is specific gravity?
Answer; It is used in a gravimetric – volumetric relationship in soils (or defined as the ratio of
the wt. in air of an equal volume of water at a stated temperature)
287. What is the approximate area for density control strips?
Answer: 335 sq. m
288. What Item of work is embankment?
Answer: Item 104
289. What kind of material for Item 200?
Answer: Aggregate sub – base course
26
290. What is the required particle size for selected borrow for toppings under Item 104?
Answer: All particle size will pass sieve 75 mm or 3” openings and not more than 15 mass %
will pass 0.075 mm. (AASHTO T 11)
291. What is the minimum degree of compaction for Item 200 and 201?
Answer: 100%
292. What is the highest point in the moisture density curve of the moisture density relation test or
compaction test?
Answer: Maximum dry density (MDD) and Optimum moisture content (OMC)
293. What is the required size of calibrated sand used for field density test (FDT)?
Answer: Any clean, dry, free – flowing, uncemented sand passing No. 10 and retained No. 200
sieve
294. What is the standard diameter of an orifice of an FDT sand cone?
Answer: ½ inch (12.7 mm)
295. What are the apparatus used in FDT?
Answer: sand cone, jug (at least 4 liters), guide plate, moisture cans, calibrated sand, weighing
scale, oven with temperature control, chisel or digging tool, plastic bags and labeling materials
(tag name)
296. How many hours does a fine aggregate tested for specific gravity and absorption be soaked in
water?
Answer: 15 to 19 hours
297. How to determine if the fine aggregate reaches the saturated dry condition?
Answer: It is determined by the use of cone test for surface moisture. If the molded shape of
fine aggregate slumps slightly, it indicates that it has reached a surface dry condition
298. What are the tests required for concrete aggregates?
Answer: Fine aggregate = grading, specific gravity, absorption, dry unit weight: Coarse
aggregate = grading, specific gravity, absorption, dry unit weight an d abrasion
Note: Soundness test is also performed as per request
299. What are the size or diameter and weight of cast – iron spheres used in abrasion test?
Answer: Approximately 46.8 mm Ø and each weighing between 390 – 455 grams
300. What is the required total weight of sample for abrasion test of coarse aggregate, grading A with 12
as number of spheres?
Answer: 5,000 grams ± 25 grams
301. What is significance of abrasion test?
Answer: It evaluates the structural strength of coarse aggregate. It gives an indication of
quality as determined by resistance to impact and wear. It also determines whether the
aggregates will have degradation during traffic or rolling.
27
302. What is the sieve used in sieving materials for abrasion test?
Answer: No. 12 (1.70 mm)
303. At what age should a concrete beam sample be tested for flexural test?
Answer: 14 days
304. How to compute the flexural strength of concrete beam sample tested at third point?
Answer: R = PL
bd2
305. How to compute the flexural strength of concrete beam sample tested at center point?
Answer: R = 3PL
2bd2
306. What is the size of the tamping rod used is sampling concrete?
Answer: 16 mm Ø and 610 mm long with the tamping end rounded to a hemispherical tip of
the same Ø as the rod.
307. Concrete masonry (hollow blocks) if subject to test, how many samples are required?
Answer: 6 pcs/10,000 units (12 pcs if more than 10,000 units)
308. What is the strength requirement for load bearing concrete masonry units?
Answer:
Individual = 5.5 MPa (800 psi) minimum
Average (for 3 samples) = 6.9 MPa (1000 psi) minimum
309. What is the strength requirement for non – load bearing concrete masonry units?
Answer:
Individual = 3.45 MPa (500 psi) minimum
Average (for 3 samples) = 4.5 MPa (600 psi) minimum
310. What is the significance of testing reinforcing steel bars?
Answer: To determine the yield and tensile strength of the bar as well as its elongation and is
used to classify the bars into grade.
311. What is the significance of bending test for RSB?
Answer: To evaluate the ductile properties of RSB
312. What is the required testing requirement for paints?
Answer: 1 can (gal or pail)/ 100 cans (gal or pail)
313. SS – l or SS – lh is what kind of asphalt?
Answer: slow – setting emulsified asphalt
314. For how many hours or how long shall a bituminous prime coat be left undisturbed?
Answer: 24 hours
315. What kind of asphalt is used as tack coat?
Answer: cut – back asphalt
316. One (1) set of concrete cylinder sample shall be taken for every how many pieces of RCCP?
Answer: 25 pieces
28
317. What is being determined in a core sample from asphalt pavement?
Answer: thickness and density of pavement
318. All records regarding quality control such as accomplishment, daily activities, weather, etc. are
recorded in a _____
Answer: Materials logbook
319. The Standard Penetration Test (SPT) is an in – situ test that measures what?
Answer: depth of soil layer
320. The main problem associated with wrong practice of conveying concrete is called _____
Answer: segregation
321. A one – lane road with a pavement width of 3.5 m and shoulder width of 0.5 m on each side of the
pavement was designed to have subbase and base courses with a combined thickness of 300 mm. If
the thickness of the subbase is 125 mm, the spreading and compaction of the base and subbase
courses shall be carried out in _____?
Answer: three (3) layers over the full width of 4.5 m
322. During the application of the first half of the anticipated load a _____ rate of loading shall be
permitted?
Answer: higher
323. Quality of factory – produced RCCP may be best established through what?
Answer: Test of concrete pipe samples
324. Soft and unstable soils were encountered during the course of subgrade preparation. If you were the
ME assigned to the project, what is the most effective and cheaper method that you would
recommend to stabilize the soil prior to the construction of the subbase course?
Answer: geotextiles
325. How many times per layer should a concrete specimen molded in a 6” x 6” x 21” beam mold be
rodded?
Answer: 63 blows/layer
326. Rolling of bituminous mix shall be discontinued whenever it begins to produce excessive _______
or _______.
Answer: pulverizing of the aggregate, displacement of the mixture
327. In placing concrete, the required temperature should be less than ____
Answer: 29ºC
328. How many concrete cylinder samples is required for a 300 pcs RCCP?
Answer: 12 sets
329. If concrete cylinder is not available for a 300 pcs RCCP, how many pipes shall be subjected to test?
Answer: 6 pcs RCCP
29
330. If there is a necessity to add water to the concrete mix in order to increase its workability (provided
concrete does not excced specified slump), how many minutes after the initial time of mixing does
adding water be permitted?
Answer: not exceeding 45 minutes and that water – cement ratio is not exceeded.
331. What are the two (2) types of bitumen that are commonly used in the bituminous mixture?
Answer:
TAR – is a viscous liquid obtained from the distillation of coal or wood.
PETROLEUM ASPHALT – are the products of the distillation of crude oil.
332. What are the three (3) major petroleum asphalts?
Answer: Asphalt cement, cut – back asphalt, emulsified asphalt
333. What are the solvents of cut – back asphalts?
Answer:
GASOLINE – for rapid – curing type
KEROSENE – for medium curing type
DIESEL – for slow curing type
334. Emulsified asphalts are either _____ or _____.
Answer:
CATIONIC EMULSION – works better with wet aggregates and in cold
weather. It is a positively charge electron.
ANIONIC EMULSION - adheres better to aggregates which have positive charge. It is a
negatively charge electron.
335. What is the bituminous material used in Item 310?
Answer: asphalt cement
336. What greatly affects the service of asphalt cement?
Answer: grade and quantity of asphalt
337. What influences primarily the grade of asphalt selected?
Answer: climatic condition
338. How many weeks do the producer of asphalt mix or the contractor shall submit the job – mix
formula?
Answer: three (3) weeks
339. Who will approve the job – mix formula?
Answer: DPWH PE and ME
340. The job – mix formula contains provisions the following:
Answer:
a. grading of aggregates
b. percentage and type of asphalt
c. temperature of aggregates and asphalt
d. temperature of mixture upon delivery or time of compaction
341. When tar is used, what is the temperature that the mixture shall be placed?
Answer: 66ºC to 107ºC
342. When is the right time to compact in order to attain the required density?
Answer: when the mixture is still hot and workable
30
343. What is to be done in order to determine the number of passes that would attain the required
density?
Answer: trial section
344. What needs to be controlled during the mixing and compaction and is of great significance in the
strength of the resulting pavement?
Answer: temperature
345. In Item 310, how is rolling be done?
Answer: It should begin from the sides and proceed longitudinally parallel towards the center
line, each trip overlapping one half the roller’s width.
346. After the final rolling, what will be checked?
Answer: degree of compaction
347. The compacted pavement shall have a density equal to or greater than _____
Answer: 95% of the laboratory compacted density
348. When will the traffic be permitted to utilize the pavement?
Answer: when the pavement has cooled to atmospheric temperature
349. How do we take sample from the finish pavement?
Answer: by the use of core drill or saw
350. What is the allowable slump of a workable concrete if not vibrated?
Answer: 40 mm – 75 mm
351. What is the allowable slump of a workable concrete if vibrated?
Answer: 10 mm – 40 mm
352. When concrete is mixed in a central mixing plant, what is the time of mixing?
Answer: not less than 50 seconds or more than 90 seconds
353. In transporting concrete, what is the time elapsed from the time water is added to the mix until the
concrete is deposited in – place at the site?
Answer: It shall not exceed 45 minutes if hauled in non – agitating trucks and 90 minutes if
hauled in truck mixers or agitators
354. How is concrete consolidated?
Answer: by the use of vibrator inserted in the concrete vertically
355. If the lanes are concreted separately, what kind of joint in a form of a keyway is used?
Answer: longitudinal construction joint
356. What kind of bar is placed perpendicular to the joint stated in the preceding problem?
Answer: deformed steel tie bars
357. What is the depth of the weaken plane joint when sawed with a concrete saw?
Answer: not less than 50 mm
31
358. The width of the weaken plane joint is _____
Answer: not less than 6 mm
359. What shall be done if cracks appear at or near the joint prior to the time of sawing?
Answer: sawing shall be omitted
360. Tie bars shall not be coated or painted with _____
Answer: asphalt or other materials
361. What is the material that is used as a load transfer device held in a position parallel to the surface
and center line of the slab of pavement?
Answer: dowel
362. To protect dowels from corrosion and to facilitate sliding in concrete, it shall be coated with _____
Answer: thin film of bitumen
363. The surface of the pavement shall be roughened by means of _____
Answer: brooming
364. What is the depth of corrugation produced by brooming in the surface of the pavement?
Answer: 1.5 mm
365. The surface of a newly put concrete when has sufficiently set shall be cured for a period of _____
Answer: 72 hours
366. The curing of the pavement is done by means of the following:
Answer:
a. by covering the concrete with mats saturated with water
b. by thoroughly wetting the pavement
c. by ponding
d. by applying curing compound immediately after finishing of the surface
367. When is the right time to seal the joints?
Answer: after the curing period or before it is opened to traffic
368. What is the difference between Item 504 and Item 505 (bluebook ’95)?
Answer: the placement of stone or boulders and the ratio of cement and fine sand
369. The ME of the contractor is directly under the supervision of the _____?
Answer: Materials Engineer of the DPWH
370. The requisites in transporting samples of the laboratory is _____
Answer: Well packed in durable containers to avoid damages in transit, accompanied by a
sample card filled up in detail and duly signed by the ME
371. Who has the power to recommend the acceptance or rejection of construction materials for use in
the project based on test results?
Answer: Materials Engineer of the DPWH
372. It is a chemical composition of asphalt that gives color and hardness.
Answer: asphaltene
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373. The mineral filler which is used in the bituminous mix is passing sieve?
Answer: No. 200
374. Cold mix asphalt is used in _____
Answer: pothole patching
375. VMA means
Answer: Voids in Mineral Aggregates
376. The compaction temperature in molding the bituminous mixture specimen
Answer: 124ºC
377. The mixing temperature of bituminous mix is
Answer: 163ºC
378. The heating temperature of bituminous mix is
Answer: 121ºC - 188ºC
379. The heating temperature of aggregates ranges from
Answer: 177ºC - 191ºC
380. The maximum absorption content of CHB
Answer: 240 kg/m3
381. The maximum moisture content of CHB
Answer: 45%
382. SPT means
Answer: Standard Penetration Test
383. A tube sampler is used in sampling undisturbed sample
Answer: Shelby tube
384. Used in sealing undisturbed sample
Answer: wax
385. A tube sampler used in sampling disturbed sample
Answer: split spoon sampler
386. It is a dynamic test used in the field to obtain rapid empirical results which can be used to estimate
shear strength and bearing capacity
Answer: Standard Penetration Test
387. A type of coring bit used in rock coring
Answer: diamond bit
388. CQCA means
Answer: Certificate of Quality Control Assurance (submitted weekly)
389. The specific gravity of asphalt ranges from
33
Answer: 1.01 – 1.04
390. The type of electron present in rapid curing emulsified asphalt?
Answer: cationic
391. How many group of three in – situ densities are required if the compacted volume of embankment
laid was estimated to be 1,500 cu. m with a thickness of 200 mm/layer?
Answer: fifteen (15)
392. The allowable % variation in mass of deformed reinforcing steel is
Answer: 6% maximum under nominal stress
393. The maximum allowable % phosphorous content of a deformed and plain billet steel bar is
Answer: 0.06%
394. Tensile and yield strengths of steel bars?
Answer:
TENSILE STRENGTH YIELD POINT
GRADE 40 483 MPa 276 MPa
GRADE 60 621 MPa 414 MPa
GRADE 75 689 MPa 517 MPa
395. Plasticity index is an indication of percent
Answer: clay content
396. The condition of the soil to be tested in the laboratory compaction test is
Answer: air – dried condition
397. The method in the determination of density of soil in – place
Answer: Sand cone method
398. Air –dry sand used in the density apparatus is passing
Answer: sieve No. 10 retained No. 200
399. Which of the following items does not need CBR?
Answer:
a. subbase materials
b. surfacing materials
c. base course materials
400. In abrasion test, the abrasive charge shall consist of cast – iron spheres or steel spheres.
Answer:
GRADING A – 12 spheres
GRADING B – 11 spheres
GRADING C – 8 spheres
GRADING D – 6 spheres
401. In truck mixing, the minimum number of revolutions after all ingredients including water is in the
drum is
Answer: 100 rpm
34
402. A maximum time of _____ shall be permitted for wet mixing, lay down and finishing when this
method is used (Item 206)
Answer: two (2) hours
403. Traffic shall be prohibited from traveling at the speeds in excess of _____ until the asphaltic
material has set.
Answer: 40 kph
404. Mortar shall be used within _____ after its preparation
Answer: 90 minutes
405. In placing concrete for slab, using buggies, the correct method that should be followed is
Answer: concrete should be dumped into the face of the previously placed concrete.
406. There is a failure of flexural strength in the pavement, if you are the ME of your firm, what will
you recommend?
Answer: conduct recoring
407. When loads have been arriving at the spreader with the material peaked or doomed up and a load
suddenly appears in which the material lies flat, it indicates
Answer: excessive asphalt
408. Where and when was the first use of Portland cement?
Answer: Bellafontaine, Ohio (1893)
409. The curve in the logarithmic scale where the 25th
blow is projected in order to determine the
liquid limit of the soil.
Answer: Flow curve
410. Percentage of wear represents the value of _____
Answer: abrasion loss
411. In the design of concrete mix, what is the volume of water in the concrete mix that produces a
slump of 76.2 mm?
Answer: 24.7 liters
412. The standard fineness modulus of sand is about _____
Answer: 2.75
413. The standard packaging weight of cement
Answer: 40 kg/bag
414. It is an impervious membrane applied to concrete pavement before its initial setting that prevents
rapid evaporation of water from the mix.
Answer: curing compound
415. The type of paint that is used for zone marking, traffic lanes and parking spaces which is rapid
drying, resistant to abrasion and weather conditions and possess improved visibility at night.
Answer: reflectorized paint
35
416. An ingredient in the paint that gives reflection during night time.
Answer: glass beads
417. The paint which is used on concrete or masonry units.
Answer: Latex
418. The average loss in weight of three specimens in zinc coating test.
Answer: Triple spot test
419. One the three specimens in the triple spot test with lightest coating.
Answer: Single spot test
420. The type of paint that is used in wood surfaces. It is a special type of paint made with varnish as
the vehicle.
Answer: Enamel
421. Group index is an empirical number ranging from 0 to 20 under average conditions of good
drainage and adequate compaction. The supporting value of a material as subgrade may be assumed as
an inverse ratio to its group index, that is a group index of zero indicates
Answer: good subgrade material
422. It determines the target density which is constructed at the beginning of the work on each course of
material to be compacted.
Answer: Control strips
423. The instrument used in placing concrete in water in a compact mass in its fina position.
Answer: tremie with 250 mm Ø
424. The maximum specific gravity of thermoplastic paint.
Answer: 2.15
425. The softening point of a thermoplastic paint.
Answer: 102.5ºC
426. The maximum drying time of thermoplastic paint.
Answer: 10 minutes
427. The rate of application of traffic paint.
Answer: 0.33 lit/m2
428. The maximum drying time of traffic paint.
Answer: 15 – 30 minutes
429. The minimum weight of sample for reflectorized paint.
Answer: 10 kg
430. The apparatus used to measure the thickness or height of compacted bituminous paving mixture.
Answer: vernier caliper
431. It is used in calculating the unit weight of the mixture of the degree of compaction of the asphalt
pavement.
36
Answer: Bulk specific gravity of compacted bituminous mixtures using saturated surface dry
specimens.
432. The solvent in the extraction of bitumen.
Answer: gasoline
433. The percent of bitumen is computed based on
Answer: mass of dry aggregates
434. The method used to determine the grading of aggregate extracted from bituminous mixture.
Answer: Mechanical analysis of extracted aggregates
435. A device used to determine the relative hardness of asphalt.
Answer: penetrometer
436. Volatization test which measures the relative proportion of asphalt to oil.
Answer: Distillation
437. The measurement wherein the asphalt begins to melt.
Answer: Softening point
438. The Index of Retained Strength (IRS) is computed through the formula
Answer: (Wet Stability/Dry Stability) x 100%
439. The temperature requirement in initial rolling for Item 310.
Answer: 200˚F to 225˚F
440. What is the color of asphalt when it is overcooked?
Answer: yellowish brown
441. How many gradation ranges for Hot Plant Mix bituminous pavement are there in the blue book?
Answer: seven (7)
442. How many gradation ranges for Cold Plant Mix bituminous pavement are there in the blue book?
Answer: two (2)
443. The cored sample of asphalt pavement is measured at
Answer: approximately quarter points
444. Too much asphalt in the bituminous mixes causes
Answer: bleeding
445. What is the plasticity index of mineral filler?
Answer: not greater than 4
446. The wearing away of pavement surface caused by dislodging of aggregate particle.
Answer: raveling
447. The interconnected cracks forming a series of small blocks resembling an alligator’s skin or
chicken wire.
Answer: alligator cracking
37
448. It is prescribed in each project based on estimated quantities and specifies the kind and number of
test of each item of work.
Answer: Minimum Testing Requirements
449. If the coarse aggregates are subjected to five cycles of sodium sulfate soundness test, the weighted
loss shall not exceed
Answer: 10 mass %
450. If the fine aggregates are subjected to five cycles of sodium sulfate soundness test, the weighted
loss shall not exceed
Answer: 12 mass %
451. Additives used in concrete mixing.
Answer: admixtures
452. The test that determines the resistance of aggregates to disintegration by saturated solutions of
sodium sulfate or magnesium sulfate.
Answer: Soundness test
453. The design of concrete mix specified in the bluebook is based on
Answer: Absolute Design Method
454. The initial setting time of Portland cement is not less than
Answer: 45 minutes
455. The final setting time of Portland cement
Answer: 10 hours
456. The standard sand used in testing the mortar strength of Portland cement
Answer: Ottawa sand
457. The apparatus used to determine the fineness of Portland cement by air permeability
Answer: Blaine Air Permeability Apparatus
458. A mixture of cement and water is
Answer: cement paste
459. The apparatus used to determine the initial and final setting of Portland cement in the laboratory.
Answer: Gillmore needle
460. The compressive strength of cement mortar samples in 7 days is
Answer: 19.3 MPa
461. What is the appearance of the molded cement paste which fails to meet the autoclave?
Answer: crumbled
462. The critical number of days of curing of concrete
Answer: first seven (7) days
463. It is the equally as important as testing, and the sampler shall sue every precaution to obtain
samples that will show the nature and condition of the materials which they represent.
Answer: sampling
38
464. A soil sample received from the field for subsequent tests by reducing aggregations of particles
into sizes which will pass certain sieves.
Answer: disturbed samples
465. A procedure to recover relatively undisturbed soil samples suitable laboratory tests of structural
properties.
Answer: thin – walled tube sampling
467. The representative who will witness the testing of materials in an accredited laboratory.
Answer: government
468. Samples obtained from the field with minimum disturbance by using any drilling equipment that
provides clean hole before insertion of thin – walled tubes that is, both the natural density and moisture
content are preserved as much as practicable.
Answer: undisturbed samples
469. The type of additive that is used to delay the setting of fresh concrete.
Answer: retarder
470. The type of additive that is used to attain maximum early compressive strength of concrete.
Answer: accelerator
471. The best enemy of construction.
Answer: water
472. The following are considered unsuitable materials:
Answer:
a. Materials containing detrimental quantities of organic materials such as grass, roots
and sewage
b. Highly organic soils such as peat and muck
c. Soils with LL exceeding 80% and/or PL exceeding 55%
d. Soils with a natural moisture content exceeding 100%
e. Soils with very low natural density, 800kg/m3
f. Soils that cannot be properly compacted as determined by the engineer
473. What is the spec of mass % passing in sieve No. 200, grading A for aggregate base course?
Answer: 0 – 12%
474. The rate of application of special curing agent
Answer: 4 liter per 14 sq. m
475. The method of measurement for determining the depth of the river channel.
Answer: sounding
476. If the type of soil in Item 200 is non – plastic, what Atterberg limit test can be performed?
Answer: Liquid limit test
477. The minimum penetration of the preservatives into the surface of timber is
Answer: 20mm
39
478. The engineer shall be notified at least _____ before the treating process of timber.
Answer: 10 days
479. All grout shall pass through a screen with a _____ maximum clear opening.
Answer: 2mm
480. The allowable height of fall in driving piles to avoid injury using gravity hammer.
Answer: 2.5m – 3.5 (concrete)
4.5m (timber)
481. This increases the shearing strength of aggregates of any size, shape and gradation.
Answer: Compaction
482. In general, soils high value of this and plasticity index are poor as engineering materials.
Answer: liquid limit of fines
483. The recommended thickness of Hot Mix asphalt overlay depending on the expected traffic and the
modulus of the cracked and seated pavement section.
Answer: 3” to 5”
484. Stabilization and under sealing are recommended if the mean deflection is ____ or the differential
deflection is ____.
Answer: greater than 0.14”, greater than 0.002”
485. Super plasticizers can reduce the water content by _____ and increase the 24 – hour strength by
_____.
Answer: 25% to 35%, 50% to 70%
486. Loose material is removed from all joints, cracks and areas that have previously patched by
asphalt by _____ with nominal _____ air pressure.
Answer: power sweeping and air blowing, 100 psi
487. Admixtures which can help incorporate a controlled amount of air on the form moist in concrete
during mixing without significantly altering the setting or the rate of characteristic of concrete.
Answer: air entraining admixtures
488. It is the activity of monitoring planned scheduled against actual and by speed task to make – up
for the past or future loss of time.
Answer: Delivery control
489. Bowl – shaped holes of various sizes in the pavement surface.
` Answer: potholes
490. A form of plastic movement typified by ripples (surface waves) across the pavement.
Answer: corrugation
491. A form of plastic movement resulting in localized bulging of the pavement.
Answer: shoving
492. Longitudinal surface depression in the wheel paths.
Answer: rutting
40
492. It is the chief load – bearing of gravel road?
Answer: base or subbase course
493. The maximum distance of the discharge point from the point of deposit by pneumatic means.
Answer: 3 meters
494. It reduces the vertical compressive stress induced by traffic in the subbase and subgrade.
Answer: base course
495. Minimum separation of splices when staggered.
Answer: 40 times bar Ø
496. Consist of furnishing, placing and finishing concrete in all structures except pavements
conforming to the lines, grade and dimension.
Answer: Structural concrete
497. Minimum grouting pressure of bonding tendons.
Answer: 0.6984 MPa (100 psi)
498. The main cross member of Bailey bridge that carry the roadway structure.
Answer: transom
499. Coring sampling shall be done at _____ interval by using split spoon sampler and the depth
needed is _____.
Answer: one (1) meter, 30m
500. What is the diameter of split spoon sampler?
Answer: 50mm
501. The uniform sampling run in core drilling.
Answer: 1.50m length
502. The initial diameter of bore hole.
Answer: 76mm
503. What is the core bit diameter?
Answer: 67mm
504. The required spacing of bore holes along centerline of roads for 300 VPD traffic.
Answer: 250m (1.5m below subgrade)
505. The required spacing of bore holes along centerline of roads for less than 300 VPD traffic.
Answer: 500m (along centerline)
506. The required spacing of bore holes along centerline for new road on swampy or marshy ground.
Answer: 100m (2m along the centerline of new road)
507. The required spacing of bore holes for bridge project
Answer:
41
1 deep drill for each abutment (30m run)
1 boring for each pier for multi – span (3m into the bed rocks)
508. The required spacing and depth of bore holes over foundation area of dam.
Answer: 60m spacing, 30m intermediate along centerline
Depth = ½ times base width
509. For ports and harbors projects:
Answer: 30m to 150m; 1m below dredged bottom (12m minimum for piers & wharves)
510. For buildings (large area – greater than 930 m2):
Answer: 1 bore hole at each corner of the structure and one on the interior (9m below lowest
foundation)
511. For buildings less than 930 m2
Answer: two (2) boring at opposite corners
512. This reflector shall be the short type having a minimum base area of 180mm x 140mm.
Answer: Flush Surface Reflector
513. Occurs on PCCP when the cutting of weakened plane is delayed.
Answer: shrinkage cracking
514. What is the primary purpose in establishing design criteria in design?
Answer: consistency
515. Positional tolerance of duct tubes during casting operations.
Answer: ± 4mm
516. This method is usually adopted when there is no visible evidence of termite infestation.
Answer: Cordoning
517. This method is used when soil shows termite infestation.
Answer: Drenching
518. Moisture content of rough lumber should not exceed _____
Answer: 22%
519. Moisture content of dressed lumber should not exceed _____
Answer: 14%
520. Design pressure of glass in glazed position.
Answer: 244 kg/m2
521. The minimum pressure of testing water tank.
Answer: 1,033.50 KPa
522. The minimum energy per blow of diesel hammer on concrete/steel pile at each stroke.
Answer: 831.48 kg/m
523. The minimum distance allowed for the top portion of the splice below ground line or seabed.
42
Answer: 2.5 meters
524. Consist of the excavation of river beds, bottom of creeks or esteros and other bodies of water.
Answer: dredging
525. The slope of batter piles
Answer: 1:6
526. Longitudinal gutter grades shall not be flatter than ____
Answer: 0.12%
527. Allowance for sediments or debris provided in design
Answer: 20%
528. It is the digging of soil after the final marking of the building outline has been established on the
ground.
Answer: Minor excavation
529. It requires wide excavation of total extraction bearing capacity.
Answer: footing
530. This shall be conducted for buildings three (3) storey and above.
Answer: Boring test
531. The minimum depth of CHB wall footing of other minor structure on the ground.
Answer: 700mm
532. The minimum depth of footing on a well compacted fill.
Answer: 100mm
533. Typically a plain or reinforced concrete that is usually provided to support a column.
Answer: Spread footing
534. Gabion dimensions are subject to tolerance limit of _____ of the manufactured state.
Answer: ± 3%
535. A field density result of 88% degree of compaction obtained on the subgrade indicates that
Answer: compaction of the subgrade fails the compaction specs and needs additional
compaction
536. Liquid limit is usually
Answer: greater than plastic limit
537. The blue book requires that the base course be compacted at least
Answer: 100% modified proctor
538. As construction work progresses, you noticed that the delivered materials are different from the
on tested passed. If you are in doubt, what will you do?
Answer: conduct immediate re – testing for verification
539. Which of the following is not the responsibility of the Materials Engineer?
43
Answer:
a. sampling of material
b. analysis of test result of material
c. scheduling of delivery of materials
d. design of concrete mix
540. Measure of construction materials for concrete structure shall be
Answer: volume
541. The moisture density curve if different from each soil. Which of the ff statement is true?
Answer:
a. granular, well graded soil generally have fairly high maximum density at low
optimum moisture content
b. clay soil have lower densities at OMC than granular, well graded soil
c. granular, well graded soil have greater densities than uniform soil at OMC
d. none of the above
542. What should be done on the subbase course with existing moisture content of 10% higher than the
optimum moisture content?
Answer: dry out to reduce moisture, spread to the required thickness and compact
543. The DPWH specs provide _____ tolerance for asphalt pavement thickness
Answer: - 5mm
544. Geosynthetics may be used for
Answer: filtration or drainage, reinforcement, erosion control
545. Which of the ff. is not included in determining moisture content?
Answer:
a. beam balance
b. oven
c. moisture can
d. extruder
546. Steel bars are considered undersize if
Answer: its nominal diameter as determined by caliper doesn’t meet the manufactured size
547. Samples of aggregates for base course when tested for quality the requirements
except grading. What will you recommend?
Answer: reprocess the materials by blending
548. Concrete curing refers to
Answer: procedure done to maximize concrete strength
549. What is the most inferior type of soil as to its engineering properties?
Answer: organic
550. What is the testing soil that involves the application of energy and addition of water as lubricant?
Answer: Moisture – Density relation test
551. The dividing line between gravel and sand in concrete pavement is
Answer: No. 10
44
552. What is the volume of the mold using 6” for AASHTO T – 180 D method in compaction test?
Answer: 0.002124 m3
553. A material resulting from the disintegration, grinding or crushing of rock and which will pass
2.00mm sieve and be retained on the 0.075mm sieve
Answer: sand
554. What is ASTM?
Answer: American Society for Testing & Materials
555. What is AASHTO?
Answer: American Association of State Highway & Transportation Officials
556. DPWH thru Bureau of Research & Standards has prepared a revised laboratory
testing procedure manual, in order to have be consistent with the latest methods as prescribed
under
Answer: ASTM & AASHTO
557. What is the category of contractor that are required by DPWH to have laboratory equipments or
apparatus in pre – bidding qualifications?
Answer: large
558. What is the maximum size of aggregate used in Item 104?
Answer: ½ of the thickness
559. What kind of material that passes .001mm sieve?
Answer: colloids
560. In soaking sample for CBR, the water should at least _____ above the specimen
Answer: 25mm
561. A natural or prepared mixture consisting predominantly of stone, gravel or sand and containing
silt – clay materials
Answer: soil aggregates
562. A rock fragment usually rounded or semi – rounded with an average dimension between 75mm –
305mm
Answer: boulders
563. The process of cutting the branches around a tree on the roadside to make them denser and grow
straight.
Answer: Pruning
564. The road near or abutting a bridge.
Answer: Approach
565. Settlement of right of way problems should be done
Answer: before the construction work
45
566. Material that has the greatest load carrying capacity
Answer: sand and gravel
567. In hydrographic survey, sounding joints should be made at a maximum interval of
Answer: 20 meters
568. The use of geofabric material to increase the strength of the subgrade
material for road construction is classified as
Answer: Soil Reinforcement Method
569. What to recommend if the surface test of newly asphalted which showed a lump
Answer: remove and replace the pavement area with irregularity
570. Controlled Density Method in embankment construction involves
Answer: Depositing and spreading materials in layers of not more than 225mm depth, loose
materials and extending to the full width of the embankment
571. What type of cracks will appear on concrete if it was not cured immediately after final placement
especially during the first seven days?
Answer: Plastic shrinkage cracks
572. What is commonly used as curing media for fresh concrete?
Answer: Liquid membrane forming
573. What is the work sequence on cylinder specimen?
Answer: cylinder shall be prepared, cured and tested at the specified date
574. When to remove the false work of continuous structure?
Answer: when the 1st and 2
nd adjoining span on each side have reached the specified strength
575. It is generally either a soft soil composed largely of silt, clay, organic deposit or loose sand having
high void rather and usually not high water content
Answer: Weak Subgrade
576. What is Twelve – Inch Layer Method Embankment?
Answer: the material shall be deposited and spread in layers not more than 300 mm in depth
(12”) loose measure, parallel to the finished grade and extending to the full width of the
embankment
577. What is Rock Embankment Method?
Answer: the material shall be deposited on the fill and push over the end of the fill by means
of bulldozer. This method is only applicable to fill ≥ 1.2 m in depth. It shall not be placed
within 600 mm of the other grade
578. What is Hydraulic Fill Method Embankment?
Answer: the material shall be taken from borrow locations and shall be deposited so as to
form the grade and cross section and shall be thoroughly compacted
579. What is the principal factor used in determining the thickness of the pavement?
46
Answer: STRENGTH OF SUBGRADE (deterioration due to frustration move also be
considered)
580. What is Placing and Removing Surcharge Method Embankment?
Answer: were unsuitable material is present under the embankment corrective work consists
of placing a surcharge constructed to the full width of the road bed. The surcharge shall
remain in place until the embankment has reached stability or the required settlement
581. What is Hydraulic Construction Method Embankment?
Answer: this involves the introduction of water into the embankment to accelerate
consideration
582. Mixture of fine – grained aggregates, bituminous binder and water for surface sealing
Answer: slurry seal (bituminous slurry)
583. What is the formula for percentage of wear?
Answer:
Percentage of wear, % = (orig wt. – wt. retained @ sieve # 12) x 100
original wt.
584. Free bitumen on the surface of the pavement which creates a shiny, glass – like reflecting surface
that usually becomes quite sticky
Answer: bleeding
585. Occurring usually at the transverse cracks joint caused by excessive expansion of the slabs during
hot weather
Answer: buckling
586. The splitting of concrete surface material from the concrete pavement
Answer: crushing
587. The authorized hauling of materials in excess of the of the free haul distance
Answer: Overhaul
588. If slurry (wet) lime is employed, what is the typical slurry ratio?
Answer: 1 tonne lime : 2 cubic meter of water
589. What is the amount of cement to be added to the soil aggregates in Item 204?
Answer: 6 – 10 mass % of the dry soil
590. Who is the father of Soil Mechanics?
Answer: Dr. Karl Terzhagi
591. What is quality?
Answer: It the degree of excellence
592. What is control?
Answer: Is to regulate
593. What is quality control?
Answer: It is conformance to requirements
47
594. What is assurance?
Answer: it the degree of certainty
595. What are the two kinds of control activities?
Answer: Inspection and Testing
596. What is the minimum distance of water table from subgrade level?
Answer: 4 – 5 feet
597. What is the process of combining two or more soil in suitable properties to produce good grading
on gravel, sand, silt and clay?
Answer: Mechanic Stabilization
598. What is the common material employed in stabilizing the moisture content of soil or liquid and
hydroscope in nature? It is an aid in the compaction process by slowing the rate of evaporation of
moisture from the soil
Answer: Calcium chloride or rock salt
599. When do clay and granular soils become unstable?
Answer: Clay soil becomes unstable if moisture content increases. Granular material becomes
unstable if it has dried
600. Why do liquid asphalt was introduced in road construction aside from asphalt cement?
Answer: It was introduced in order to save heating costs and from convenience in road –
mixing or priming
601. The theory of concrete design mix is to
Answer: Optimize aggregate packing and optimizes properties of cement mortar
602. To optimize the properties of the cement mortar, one has to depend on
Answer: cement type, cement content and water content
603. What type of cement is the Ordinary Portland Cement (OPC)?
Answer: Type I
604. What type of cement is the Moderate Sulphate Resistant Portland Cement?
Answer: Type II
605. What type of cement is the Rapid Hardening Portland Cement?
Answer: Type III
606. What type of cement is the Low Heat Portland Cement?
Answer: Type IV
607. What type of cement is the High Sulphate Resistant Portland Cement?
Answer: Type V
608. What type of cement is the Portland Blast Furnace Slag Cement?
48
Answer: Type 1S
609. What type of cement is the Portland Pozzolan Cement?
Answer: Type 1P
610. Type I is for general use such as
Answer: pavements & sidewalks, buildings & bridges and tanks & water pipes
611. Type III cement is used for
Answer: early stripping of forms & high early strength
612. Type IV is used for
Answer: massive structures such as dams
613. Type V cement is used for
Answer: when sulphate content of groundwater is very high
614. The inventor of Portland cement was
Answer: Joseph Aspdin
615. Portland cement is composed of blended materials containing
Answer: calcium, alumina, iron and silica
616. The simple recipe of Portland cement is
Answer: 2 parts of crushed limestone, 1 part clay/pulverized shale, 1 pinch of iron ore, then 1
pinch of gypsum added to clinker
617. Pozzolan cement is composed of a raw material called
Answer: volcanic earth
618. The 75% compressive strength of Portland cement is composed of
Answer: C3S and C2S
619. The 25% setting time of Portland cement is controlled by
Answer: C3A and C4AF
620. When water is added to Portland cement, _____ process is developed
Answer: hydration
621. Calcium Silicate Gel (C–S–H) and lime [Ca(OH)2] are developed when _____ is added to
Portland cement
Answer: water
622. When Portland cement contains a low C3A, it means
Answer: the setting time is larger
623. Surplus lime [Ca(OH)2] in Portland cement when mixed with water takes care of the concrete’s
Answer: alkalinity
49
624. Coarse aggregates can be taken from
Answer: crushed rock, slags and river gravel
625. The water required for concrete mix should be
Answer: fresh water
626. Sea water is deleterious to concrete mix unless on admixture is added because it contains
Answer: chloride
627. The entrapped air in concrete is
Answer: accidental and unwanted
628. The entrained air in concrete is
Answer: deliberate and desirable
629. We use aggregate in concrete as
Answer: filler materials in concrete
630. Aggregates are important in concrete because they strongly influence:
Answer: the properties of concrete, its mix proportion and its economy
631. Which of the following is not deleterious material to concrete?
Answer:
a. calcium
b. chloride
c. coal
d. sulphate
632. Over sanded and under sanded mixture require more water to be workable, but making it
so will only result to sacrifice in
Answer: strength
633. Concrete in the area represented by the cores will be considered adequate if the average strength
of the cores is equal to or at least _____ of the specified strength, fc’ and no single core is less than
_____
Answer: 85% of f’c, 75% of f’c
634. Fine aggregate shall be rejected when it fails in the _____ for organic impurities
Answer: Colormatic Test
635. Portland cement may be/shall be rejected if:
Answer: it has partially set, it contains lumps of cake cement and it comes from a discarded or
used bag
636. A measurement of the coarseness or fineness of aggregates
Answer: fineness modulus
50
637. An excess water needed for absorption of coarse aggregates
Answer: free water
638. What do you mean by SSD?
Answer: Saturated Surface Dry
639. A general term relating to the character of a mix with respect to its fluidity
Answer: consistency
640. More silt and clay content to fine aggregates is
Answer: objectionable
641. Type A admixture is classified by ASTM C494 as
Answer: Water – reducing admixture
642. For core specimens, each lot will be divided into how many equal segments?
Answer: five (5)
643. The unit pressure greater than which progressive settlement occur leading to failure
Answer: bearing capacity
644. The recommended thickness of hot mixed asphalt overlay
Answer: 2”
645. In the test to determine the moisture content of samples, the beam balance should be sensitive up
to
Answer: 0.1g
646. If a sample can not be weighed within the prescribed time after being removed from the oven, it
will placed inside a
Answer: dessicator
647. Plastic and finely grain soil will require at least how many hours to dry ay constant weight/mass
Answer: 4 hours
648. A sample may be cooled at room humidity and must be weighed after it has been removed from
the oven within
Answer: 1 hour
649. Drying the material sample in the oven to constant weight at a prescribe temperature; the drying
time depends on the kind of soil and size of sample. A 25-gram sample of sandy material will be
dried in about
Answer: 2 hours
650. Test conducted for buildings 3 storeys and above
Answer: Boring Test
651. A test to determine the moisture content of soil
Answer: calcium tri – chloride
51
652. The aggregate crushing value of strong aggregate is
Answer: low
653. The kind of asphalt used in overlaying seated pavement
Answer: hot – mix asphalt
654. The minimum width of paved sidewalk
Answer: 1.5 m
655. The limit of water – cement ratio of concrete
Answer: 0.50 – 0.60
656. A cement which has a cementitious effect
Answer: Portland cement
657. A concrete where compression is induced before the application of working load so that tension
under these loads is reduced
Answer: Pre – stressing
658. What laboratory test is used in determining the phosphorus content of steel materials?
Answer: Phospho - molydate
659. What chemical property in the composition of steel material that will cause brittleness or cold
shortness when its content goes beyond 0.05% to 0.10%
Answer: phosphorous
660. Base or sub base is extended beyond each edge of proposed concrete pavement
Answer: 0.60 m
661. If you want to adjust the slump and the air content, how do you it?
Answer:
± 10 mm slump = ± 2 kg/m3 from (water)
± air entrapment = ± 3 kg/ m3 of average (water)
662. In non – entrained concrete, what is the range of % air entrained?
Answer: 3% - 0.2% (small – bigger aggregates)
663. In air – entrained concrete, what is the range of air entrained?
Answer: 8% - 3% (small – bigger aggregates)
664. For a constant water – cement ratio, what will happen if air content is involved?
Answer: the strength of concrete is reduced
665. What will happen if you lower the water – cement ratio and maintaining other values of its
ingredients?
Answer: it will acquire strength
666. What is the mixing time of concrete?
Answer:
1.5 m3 capacity mixer, T ≥ 60 seconds
Above1.5 m3 capacity mixer, T ≥ 90 seconds
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667. When cement is in contact with moist aggregates, batch made by mix will be disallowed beyond
____
Answer: 1 ½ hours
668. How many hours should an aggregate be washed and stockpiled before batching starts?
Answer: 12 hours prior to batching shall be stockpiled or binned for draining
669. When will truck mixing start?
Answer: mixing shall begin within 30 minutes upon cement has due added
15 minutes when wet aggregates is used, as 32ºC temperature is present
670. Concrete delivered by agitation of truck mixer must be discharged within 1 hour or 250
revolutions of the drum or Olader. Why?
Answer: to avoid over mixing and initial setting of concrete
671. In final computation of concrete in road to be paid, what is the maximum size of pipe that is
negligible in the volume computation?
Answer: pipes with Ø of 4” or less
