Evaluation of the Strength and Abrasion Resistance of ...docs.trb.org/prp/15-3369.pdf · 1 Evaluation of the Strength and Abrasion Resistance of Pervious Concrete ... 28 third concrete

Evaluation of the Strength and Abrasion Resistance of Pervious Concrete Mixes Using 1

Three Types of Cements (GU, GUL, nanocement) 2 3

Mattia Longhi, Visiting Scholar at the University of Waterloo 4 M.Sc. Candidate 5 DICAM-Department of Civil, Chemical, Environmental, and Materials Engineering 6 School of Engineering, University of Bologna 7 Viale Risorgimento 2, 40136 Bologna, Italy 8 E-mail: [email protected] 9

10

Marcelo Gonzalez, M.Sc. 11 Ph.D. Candidate, Centre for Pavement and Transportation Technology 12 Department of Civil and Environmental Engineering 13

Faculty of Engineering, University of Waterloo 14 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1 15

Phone: +1-519-888-4567× 33872, Fax: +1-519-888-4300 16

E-mail: [email protected] 17

18

Sonia Rahman, B.Sc 19 M.Sc. Candidate, Centre for Pavement and Transportation Technology 20 Department of Civil and Environmental Engineering 21

Faculty of Engineering, University of Waterloo 22 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1 23 Phone: +1 226 606 4449 24

E-mail: [email protected] 25

26

Susan L. Tighe, Ph.D., P.Eng. 27 Professor, Canada Research Chair in Sustainable Pavement and Infrastructure Management 28

Norman W. McLeod Professor of Sustainable Pavement Engineering 29 Director of Centre for Pavement and Transportation Technology 30

Department of Civil and Environmental Engineering 31 Faculty of Engineering, University of Waterloo 32 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1 33

Phone: +1-519-888-4567× 33152, Fax: +1-519-888-4300 34 E-mail: [email protected] 35 36

Cesare Sangiorgi, Ph.D 37 Assistant Professor in Pavement Engineering 38

DICAM-Department of Civil, Chemical, Environmental, and Materials Engineering 39 School of Engineering, University of Bologna 40 Viale Risorgimento 2, 40136 Bologna, Italy 41 E-mail: [email protected] 42

43

Corresponding Author: Mattia Longhi 44 Number of words: 3919 + 2250 (nine figures) + 1250 (five tables) + 6 (6 eq.) = 7425 45 46

mailto:[email protected]

tel:519-888-4567%20x%2033872



Longhi, Gonzalez, Rahman, Tighe, Sangiorgi 1

ABSTRACT 1 2 Pervious concrete can potentially provide various environmental benefits as a stormwater best 3 management practice and is usually designed for low volume applications. It has an open void 4

structure which allows water to infiltrate and percolate to the ground, without altering the natural 5 hydrologic cycle. In this way, several problems related to the stormwater management can be 6 mitigated. 7 8 With regard to pervious concrete pavement performance, permeability is the key functional 9

design property. However, compressive strength, flexural strength and abrasion resistance are 10 also important properties. 11 12 Currently in North America, the application of General Use Limestone (GUL) cement is 13

becoming more common because it has a lower carbon footprint; CO2 emissions during the 14 cement production are reduced by approximately 10%. At the same time, nanotechnology 15

applied in cement base materials is receiving increasing attention due to the potential to obtain 16 better long term performance. 17

18 In this research two types of cement, General Use (GU) and GUL, were used in the pervious 19 concrete to determine if they would impact performance. Secondly, nanomaterials were added to 20

pervious concrete to examine if it could improve strength and durability of pervious concrete 21 pavement without adversely impacting permeability. 22

23 The control mix includes the application of GU cement, the second mix incorporates GUL 24 cement and the third mix includes the application of 2.5% nanosilica with GUL cement. 25

26

The test results show that the three different mixes behave statistically the same. However, the 27 third concrete mix with the nanosilica was shown to perform better in terms of abrasion. 28

29 30 31

32 33

34 35 36

37

38 39 40

41 42 43 44 45 46


INTRODUCTION 1 2 According to Henderson et al. (1), pervious concrete is a sustainable type of pavement material 3 which allows water to percolate through the layer, due to its pervious structure (1). This type of 4

concrete mixture has no fine aggregates and insufficient cement paste to fill the voids (2). As a 5 result, the mix contains high void content, ranging 15 to 20%, and thus is a highly permeable 6 material. The main characteristics of these mixes are: the low Water/Cement (W/C) ratio and a 7 low concrete slump. The optimal void content range of pervious concrete pavement ranges from 8 15% to 20% (1). 9

10 This permeable material is a viable solution when it comes to reducing surface run-off on roads. 11 In addition, the excess water and associated demand on a stormwater management system is 12 reduced significantly. The pervious concrete pavement is suitable for low speed applications, 13

such as: driveways, residential streets, paths, sidewalks, shoulders and parking lots. 14 15

The most important functional property of a pervious concrete pavement is permeability. This is 16 related to the void content of the mix and how it can potentially change over time. However, a 17

balance between the void content and strength of the mix must be obtained since a higher void 18 content may result in a less durable material (1). Compressive strength (CS), flexural strength 19 (FS) and abrasion resistance (ABR) are also important properties to evaluate pavement 20

performance of the top layer. 21 22

General use (GU) cement is the most common type of cement used in the North America. It is 23 composed of calcium silicates and aluminium-iron containing clinker phases and other 24 compounds. It is suitable for most conventional concrete applications such as pavements, 25

buildings, bridges, tanks, reservoirs and pipes. However, on average, the production of one ton of 26

cement produces 0.92 ton of CO2 (3). 27 28 General Use Limestone (GUL) cement is a class of portland cement containing limestone. The 29

application of GUL cement is becoming more prevalent in North America due to its lower 30 carbon footprint. Europe started to adopt usage in 2000, but many European countries started its 31

utilization one decade prior to that date (3). Since 2005, many studies in North America were 32 conducted on portland cement containing up to 15% of limestone, in efforts to produce concrete 33

in a more environmentally-friendly manner. The key advantage of the GUL cement is that it has 34 a lower carbon footprint during manufacturing. This is because the limestone is added directly to 35 the cement mix and does not need to be burned in the rotating kiln. Also, the limestone is a softer 36 material than the clinker and thus takes less energy to grind to the same fineness (4). 37

38 Nanotechnology, which involves manipulating materials smaller than 100 nm, is gaining 39 increased attention in concrete applications. In particular, adding nanomaterials in cement-based 40

materials can potentially result in superior performance in terms of compressive strength and 41 abrasion response (5). 42 43 Currently, few papers discuss the application of GUL and nanoconcrete in pervious concrete 44 pavements. In this research three different types of pervious mixes are compared in terms of 45 compressive strength, flexural strength and abrasion resistance. The first mix, defined as the 46


control concrete includes the application of GU cement. The second mix incorporates the GUL 1

cement while the third mix includes the application of 2.5% nanosilica with the GUL cement. 2 3 This study was conducted at the Centre of Pavement and Transportation Technology (CPATT), 4

at the University of Waterloo (UW) in collaboration with the Cement Association of Canada 5 (CAC) and the Natural Science and Engineering Research Council of Canada (NSERC). 6 7

OBJECTIVES AND SCOPE 8 9

The objectives of this paper are the following: 10 11 1) To evaluate the effects of using two different types of cement in pervious concrete. 12 13

2) To examine the impact that the inclusion of nanosilica has on pervious concrete. 14 15

This study involved a laboratory examination of the materials and associated performance 16 parameters namely compressive strength, flexural strength, abrasion resistance and permeability. 17

Laboratory samples were cast in order to perform the various experiments. 18

19

LITERATURE REVIEW 20 21 As cities develop, countries grow in size and population, the urbanization with structures, roads, 22

and industry grows as well. These significant changes create a series of problems related to 23 stormwater management; the most common issue is controlling the water volume (6). There are 24 three main consequences of urbanization of stormwater management: 25

26

1) The hydrologic balance is modified due to a lower amount of water infiltration to the ground. 27 2) An increase in the rates of flow to receptors is observed, which can lead to flooding control 28 problems. 29

3) Stormwater quality decreases during runoff. 30 31

A new global concept of sustainable infrastructure has been developed in recent years to reduce 32 the impact of urbanization and the problems that come with it on the environment. 33

34 Pervious concrete pavements can provide many sustainable benefits (6). According to Kevern et 35 al. (7), the porosity of the pervious concrete is created by the reduction or elimination of fine 36 aggregates from the mix design. Porosity or permeability in pervious concrete is the most 37

important functional consideration. However, in order to obtain a durable and strong product, 38 other properties must be considered. 39 40

GU cement is the most commonly manufactured type of cement in the world. It is composed of 41 hydraulic calcium silicates and it is manufactured through the blending of raw mineral at high 42 temperatures in cement rotary kilns. Rotary kilns produce an intermediate product called clinker. 43 The production of this product leads to a release of carbon dioxide (8). 44 45


Nowadays there is a greater focus on environmentally-friendly materials, thus several study 1

cases related to GUL cement were conducted. According to Bushi et al. (9), this kind of cement 2 has a lower carbon footprint and is 10% better in terms of greenhouse gas emissions. By 3 reducing the amount of clinker in the cement mix, both thermal energy use and CO2 emissions 4

are reduced. 5 6 Currently, another application which is becoming popular is the use of nanotechnology in rigid 7 pavements. The size of the calcium silicate hydrate (C-S-H) phase is only within the range of a 8 few nanometers. This component is partially responsible for the strength of the cement base 9

materials and has significant impact on the performance of concrete. Thus, nanotechnology has 10 the potential to enhance the properties of the material, improve mechanical performance, 11 durability and sustainability (10). 12

13

MATERIALS AND METHODS 14 15

Materials 16 17

The materials used in this research include the following: GU cement, GUL cement, water, 18 coarse aggregates, nanosilica in fine powder, and four different kinds of admixture: air-19 entraining admixture, set retarding admixture, high-range water-reducing (HRWR) admixture, 20

and viscosity-modifying admixture. The coarse aggregates were provided by Sarjeant Co. Ltd, a 21 private Canadian aggregate company. The mix design and associated aggregates were selected as 22

being a typical mix for usage in cold climates. The relative density of the aggregates is 2700 23 kg/m

3 and the gradation is reported below in Table 1. 24

25

TABLE 1 Pervious Concrete Aggregate Gradation 26

Sieve size

Cumulative

Weight

Retained

Individual %

Retained

Cumulative %

Retained

Sample %

Passing

% Pass Lower

Limit

% Pass Upper

Limit

19 mm 0 0.00 0.00 100.00 100 100

13.2 mm 150 1.50 0.02 98.50 90 100

9.5 mm 3050 29.00 0.31 69.50 40 70

4.75 mm 9750 67.00 0.98 2.50 0 15

Pan 10000 2.50 / / 0 0

27 28 A gradation curve is reported in Figure 1; no fine aggregates were used in this research. 29

30 31 32 33 34 35 36 37 38 39


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

FIGURE 1 Gradation curve of aggregates. 21 22

A chemical admixture is any material other than cement, aggregates, or water added to the batch 23 in a small amount (11). Several types of admixtures are available, depending on their functions. 24

Four of them are used in this pervious concrete pavement research: 25

1) Air-entraining admixture; 26 2) Set-retarding admixture; 27 3) HRWR admixture; and 28

4) Viscosity-modifying admixture. 29 30

The air-entraining admixture creates tiny bubbles of uniform size, distributed homogeneously in 31 the mix to improve the workability of the concrete (11). The set-retarding admixture extends the 32 duration of setting of the concrete without affecting the ultimate strength; in this way it remains 33 workable for longer than usual (11). HRWR admixture (superplasticizer) is a chemical, generally 34 in liquid form, which has two main functions namely: provision of high slump and it provides an 35

improved ability to reduce water content with resultant gain strength. This kind of admixture also 36 improves the workability of the concrete. It does not modify the characteristics of the material, 37

but reduces the friction in the fresh mix in a way so that the concrete can flow freely for a long 38 period (11). The viscosity-modifying admixture provides flexibility in mixture proportioning and 39 batching and provides an increased resistance to segregation that help facilitate the placement 40 and consolidation (11). 41 42

The properties of the nanosilica used in this research are (12): 43 44 1) Material: Silicon Dioxide nanopowder (Nano SiO2). 45

2) Purity: > 99%. 46

Gradation Curve

0

20

40

60

80

100

120

19 mm 13.2 mm 9.5 mm 4.75 mm Pan

Sieve Size

% P

as

sin

g

Sample % Passing

% Pass Lower Limit

% Pass Upper Limit


3) Average Particle Size: 15 nm. 1

4) Color: White Powder. 2 5) Specific Surface Area (SSA): 100 m

2/g. 3

6) Morphology: Spherical. 4

5

Mixture Design and Proportions 6 7 In order to prepare the sufficient number of samples for testing, two mixes for each type of 8 cement were prepared. The amount of materials used, for 1 m

3 of mix, is provided in Table 2. 9

10

TABLE 2 Mixture Proportions 11

Material Quantity Density (Kg/m3) Yield (m

3)

GU, GUL cement (Kg) 422 3150 0.134

Water (L) 148 1000 0.148

Coarse Aggregates (Kg) 1962 2700 0.727

Air-entraining admixture (ml) 105 1100 0.000

Set-retarding admixture (ml) 956 1000 0.001

HRWR admixture (ml) 287 1200 0.000

Viscosity-modifying admixture

(ml) 172 1200 0.000

12

In the last two mixes 2.5% of nanosilica (nano SiO2) was added, by the weight of cement, which 13 amounted to 10.55 Kg of nano SiO2. The W/C ratio was kept constant for all six batches at 0.35. 14 The volume of each batch was 0.021 m

3. The GU cement was applied in the first two batches, 15

whereas the GUL cement was used in the other two. Finally, a small amount of nanosilica was 16 mixed with the GUL cement, in order to obtain the third type of pervious concrete in this 17

research (last two batches). 18

19 Fresh Pervious Concrete Properties 20 21 Fresh pervious concrete mixes were prepared in a drum mixer in the laboratory, at The 22

University of Waterloo. The procedure used in this project is listed below: 23 24 1) Pour in the drum mixer 0.40 L of water, air-entraining admixture, set-retarding admixture, 25 coarse aggregates. Mix until all the aggregates are evenly coated. 26 2) Place cement either GU, GUL in the mixer for one minute. 27

3) Pour in 1.9 L of water while the mixer is still running. Mix for two minutes. 28 4) Add HRWR admixture to 0.40 L of water and pour into the mixer. Mix for two minutes. 29 5) Add viscosity-modifying admixture in the last 0.40 L of water. Pour into the mixer and mix 30 for two minutes. 31

32 For the batches which contain nanosilica during step 3, place nanosilica in the 1.9 L of water 33 before adding to mixture. This is to avoid the inhalation of nanomaterial particles. The mixing 34 procedure is shown in Figure 2a. 35

36


1 FIGURE 2 a) Nanosilica added in the batch b) slump test. 2

3 Testing of Fresh Pervious Concrete Properties 4 5 After all the steps were completed, the slump test was performed on the fresh pervious concrete 6 as shown in Figure 2b. In accordance with ASTM C1688/C1688M-12 (13), the density and the 7

void content were also measured. 8

9

Preparation of Hardened Pervious Concrete Test Specimens 10 11 After the measurements, the casting of the fresh pervious concrete was performed. In the first, 12

third and fifth batch, sixteen test specimens were obtained: six 100 mm x 200 mm cylinders for 13 compressive strength and ten 152 mm x 75 mm cylinders for abrasion resistance test. 14

In the second, fourth and sixth batch, six test specimens were casted: three 100 mm x 200 mm 15 cylinders for the permeability test and three 100 mm x 100 mm x 360 mm beams for flexural 16

strength. 17 All the specimens were compacted using a Standard Proctor Hammer, in accordance with ASTM 18 C1688/C1688M-12 (13). The pervious concrete was compacted in two equal layers, with the 19

Standard Proctor Hammer dropped 20 times per layer and distributed evenly across the surface 20 area of the layer. 21

After twenty-four hours the specimens were demolded carefully, in accordance with ASTM 22 C192/C192M-13a (14). Afterwards, they were placed in a curing room, inside the concrete 23 laboratory, until they reached their required time to be tested. 24

25

Testing of Hardened Pervious Concrete 26 27 Tests on the hardened specimens were performed at 7 and 28 days for compressive strength and 28

abrasion resistance as shown in Figure 3a and 3b, and at 28 days for flexural strength (Figure 4). 29 Three compressive strength tests and five abrasion resistance tests were conducted at 7 and 28 30 days in accordance with ASTM C39/C39M-12 (15) and ASTM C944/C944M-12 (16) 31

respectively. Following ASTM C78/C78M-101

(17), three flexural strenght tests were 32 conducted at 28 days. 33 34

a) b)


The abrasion machine, owned by CPATT at the UW, uses the rotating cutters method. The test is 1

performed for two minutes and after that time the loss of weight for each sample is reported. The 2 setup was properly built in order to obtain a double vertical load of 197 N and a rotation speed of 3 200 rpm, in accordance with ASTM C944/C944M-12 (16). Abrasion test simulates wear on 4

concrete pavement surface. 5 6 Although abrasion occurs in the long term performance, examination at 7 days was performed in 7 order to investigate the behaviour of the pervious concrete when early opening of pervious 8 concrete pavements to traffic may be required. 9

10

11 FIGURE 3 a) Apparatus for Compressive Strength; b) Abrasion Test with Rotating Cutter 12

Drill. 13 14

a) b)


1 FIGURE 4 Flexural Frame. 2 3

RESULTS AND DISCUSSIONS 4 5

Properties of Fresh Pervious Concrete 6 7 The properties of fresh pervious concrete are reported in Table 3, in accordance with ASTM 8

C1688/C1688M-12 (13). As is shown, the slump is always 0 mm (as can be seen in Figure 2b), 9 due to the lack of fine aggregates. 10

11

TABLE 3 Properties of Fresh Pervious Concrete according to ASTM C1688/C1688M-12 12

Types of cement Density (Kg/m3) Void Content (%) Slump (mm)

GU (1st batch) 2024.51 19.13 0

GU (2nd

batch) 2027.34 19.01 0

GUL (3rd

batch) 2038.65 18.56 0

GUL (4th

batch) 2066.94 17.43 0

GUL+ Nano SiO2 (5th

batch) 2059.87 18.86 0

GUL+ Nano SiO2 (6th

batch) 2052.80 19.15 0

13 The void content obtained is within a good range and indicates that the material will be durable. 14

Good void content values go from 15% to 20%. 15 If the void content is too high it can potentially result in less durable material, especially in 16 freeze thaw environments which can subsequently lead to major maintenance costs in the field. 17


Properties of Hardened Pervious Concrete 1 2 Compressive Strength 3 The results obtained from the compressive strength are shown in Figure 5. It is clear that test 4

specimens made with GU cement and with GUL cement behave similarly. Nanomodified 5 pervious concrete showed better resistance; however the difference is not significant (see 6 statistical analysis). 7 8 9

10

11 12 13

14 15

16

17 18 19

20 21

22 23 FIGURE 5 Compressive Strength at 7 days and 28 days. 24 25

Flexural Strength 26

Regarding this test, all three types of pervious concrete behave in a similar way. The typical 27 range reported for flexural strength is from 1 MPa to 3.8 MPa (18). 28

29 30 31

32 33

34 35 36

37

38 39 40

41 42 43 44 45 FIGURE 6 Flexural Strength performed at 28 days. 46

Compressive Strength

0

5

10

15

20

25

30

35

GU GUL NANOCONCRETE

Types of Pervious Concrete

Co

mp

res

siv

e S

tre

ng

th (

Mp

a)

7 Days

28 Days

Flexural Strength

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

GU GUL NANOCONCRETE


Mo

du

lus o

f R

up

ture

(M

pa)

28 Days


Abrasion Response 1

In this test, the third mix performed better after 7 days than after 28 days: the nanomodified 2 pervious concrete is stronger initially and is characterized by better bonds between the cement 3 paste and the coarse aggregates (see Figure 7). Results are consistent with previous studies which 4

demonstrate that nanosilica can enhance the Internal Transition Zone (ITZ) between paste and 5 aggregates. This enhancement of the bonding generates a better abrasion response in concrete 6 materials (12). Moreover, pervious concrete made with GUL cement does not perform as well as 7 the GU cement because the surface of the GUL cement is rougher than the surface made with 8 GU cement (see Figure 8). 9

10 11 12 13

14 15

16 17

18 19 20

21

22 23 24

25

26

27 FIGURE 7 Abrasion Response performed at 7 days and 28 days. 28

29

Abrasion Test

0

2

4

6

8

10

12

14

16

18

GU GUL NANOCONCRETE


Lo

ss

of

We

igh

t (g

)

7 Days28 Days


1 FIGURE 8 left) test specimen made with GU; right) test specimen made with GUL. 2 3 Permeability 4 The permeability of the pervious concrete was measured with a Gilson permeameter. In this test, 5

100 mm x 200 mm cylinders were wrapped in a latex sleeve to reduce and ideally eliminate the 6 horizontal drainage (6). Figure 9 shows how the test was performed. 7 8

9 FIGURE 9 Permeability test performed at the CPATT laboratory. 10 11


The cylinders were placed inside the larger tier and were sealed to the smaller top tier with the 1

plumber putty. The permeameter was filled with water: the time it took the water to fall ten 2 centimeters was recorded. In all cases Darcy’s Law (Equation 1) was used to determine the 3 coefficient of permeability of the pervious concrete. 4

5

6 Where: 7

8 K is the coefficient of permeability, cm/sec. 9 a is the inside cross-sectional area of the permeameter, 38.32 cm

2 for the smaller, upper 10

tier. 11 L is the length of the sample, the thickness of the core or pervious concrete, cm. 12

A is the cross-sectional area of the drainage of the permeability, 167.53 cm2. 13

t is the elapsed time between h1 and h2, seconds. 14

h1 is the initial head, cm. 15

h2 is the final head, cm. 16 17 The purpose of the permeability testing is to evaluate changes in the coefficient of permeability 18

for each mix. The mean K for each mix was found as follows: 19 20

1) K1 (GU) = 7.2 cm/min. 21 2) K2 (GUL) = 4.7 cm/min. 22 3) K3 (Nanoconcrete) = 9.9 cm/min. 23

24

25 Statistical analysis 26 27

Table 4 presents the results for the statistical analysis of all the tests performed at 7 days and at 28 28 days. For 7 day old concretes, results for compressive strength and flexural strength present 29

high variability, since the COV for compressive strength is more than 10%, as is defined in 30 ASTM C39 (15). However, results at 28 days old concretes for compressive strength and flexural 31

strength are consistent, since the Coefficient of Variation (COV) is less than 10%. The results of 32 the ABR tests are consistent in both cases (7 and 28 days) because the highest COV was found to 33 be 23%; according to ASTM C944 (16) a COV of 36% is allowed for a single operator. 34 Permeability test presents high variability too, mainly in the mix with GUL cement. Differences 35 in the level of compaction may have caused this high variability in the permeability tests. 36

37 38

39 40 41 42 43 44 45

Eq. 1


TABLE 4 Statistical analysis derived from the tests performed at 7 and 28 days 1

Hardened Pervious Concrete

Properties Type of Mix

Statistical Properties

Mean STDV COV

Results at 7 days

Compressive Strength (MPa)

GU 21.7 1.2 5.3

GUL 22.2 3.2 14.2

Nanoconcrete 26.4 2.8 10.5

Abrasion Response (Loss of weight, g)

GU 11.3 1.9 16.6

GUL 16.4 2.6 15.8


Results at 28 days

Compressive Strength (MPa)

GU 24.4 1.2 4.8

GUL 24.5 2.2 8.9


Flexural Strength (MPa)

GU 3.4 0.2 6.1

GUL 3.2 0.2 6.5


Abrasion Response (Loss of weight, g)

GU 7.9 1.3 16.3

GUL 8.5 2.0 23.0


Permeability K(cm/min)

GU 7.2 1.6 22

GUL 4.7 2.4 51

Nanoconcrete 9.9 1.1 11

2 3 An analysis of variance was carried out in order to verify the statistical differences amongst the 4 tests performed in the different mixes. The null hypothesis assumes that there is no significant 5

difference between the means (i) of each group (1 = 2 = 3). The assumed level of 6

significance was = 5% (19). If ≤ c than the evidence is insufficient to reject the null 7

hypothesis and therefore 1 = 2 = 3. The equations used in the analysis are as follows: 8 9

10 11

12 13

14 15

Eq. 2

Eq. 3

Eq. 4


1 2

3 4

Where: 5 6 x: is the mean of the entire sample (grand mean). 7 r: is the number of the groups. 8 n: is the size of the sample. 9

q1: is the sum of squares between the means of the groups. 10 q2: sum of squares within the groups. 11

v0: is a quotient. 12

c: is the solution obtained from the F-Distribution Table with degrees of freedom (r – 1, n – 13

r) and = 5% (19). 14

15 Table 5 presents the calculations for the analysis of variance. Table 5 shows that for CS, FS and 16 ABR the hypothesis test is valid, which means that all three different mixes behave statistically 17

the same. With regard to the permeability test, the hypothesis test was rejected, which indicates 18 that the means are statistically different. Since the K value for nanoconcrete is higher, this 19 implies that nanosilica is potentially able to enhance permeability. 20

21

22

TABLE 5 Analysis of Variance regarding tests at 28 days 23

24 25

26 27 28

29

Parameters for calculations Compressive

Strength

Flexural

Strength

Abrasion

Response Permeability

24.4 3.4 7.9 7.2

2 24.5 3.2 8.5 4.7

27 3.5 8.6 9.9

X 25.3 3.4 8.3 7.3

R 3 3 3 3

N 9 9 15 9

5 5 5 5

q1 13.6 0.1 0.9 40.4

q2 20.3 0.3 34.2 18.9

v0 2.0 1.2 0.2 6.4

C 5.14 5.14 3.89 5.14

Null Hypothesis Result 1 = 1 = 1 = 1

Eq. 5

Eq. 6


CONCLUSIONS AND RECOMMENDATIONS 1 2 The following conclusions based on the research presented in this paper include: 3 4

1) The GUL cement is a good alternative to GU cement since compressive strength and flexural 5 strength were found to be same statistically. 6 2) Regarding the ABR test, the GUL paste creates a surface which is rougher than the surface of 7 pervious concrete made with GU cement. This fact can lead to raveling of aggregates from the 8 pervious concrete layer. 9

3) Adding a small amount of nanosilica in the mix can initially enhance the quality of pervious 10 concrete in terms of ABR. Better bonding was found in the abrasion test at 7 days compared with 11 28 days. 12 4) The level of compaction of pervious concrete test specimens can greatly affect the 13

performance in terms of permeability as shown in the statistical analysis. 14 15

ACKNOWLEDGMENTS 16

17 The authors sincerely acknowledge the support of the Cement Association of Canada, NSERC, 18 BASF company which provided the chemical admixtures, “The Sarjeant co. Ltd” which provided 19 the aggregates, Holcim’s and St. Mary’s Cement for the cement. The authors also are grateful to 20

the technicians of the concrete laboratory at the UW and especially to Kathy Hui for the writing 21 services. 22

23 REFERENCES 24

25 1) Henderson, V., Tighe, S. L., Norris, J. Behaviour and Performance of Pervious Concrete 26

Pavement in Canada. Prepared for the presentation at the Advances in Pavement Design and 27 Construction Session of the 2009 Annual Conference of the Transportation Association of 28 Canada, Vancouver, British Columbia. 29

2) Kosmatka, S., B. Kerkhoff, R. D. Hooton, and R. J. McGrath. Design and Control of Concrete 30 Mixtures. Cement Association of Canada (CAC), 8

th Canadian Edition, Ottawa, ON, Canada, 31

2011. 32 3) Thomas, Michael D.A., Hooton, R. Doug. The Durability of Concrete Produced with Portland 33

Limestone Cement: Canadian Studies. Portland Cement Association 2010. 34 4) Hooton, R. D., Nokken, M., & Thomas, M. D. A. (2007). Portland Limestone Cement: state-35 of-the-art report and gap analysis for CSA A 3000. Cement Association of Canada Research. 36 5) Gopalakrishnan, K., B. Birgisson, and P. Taylor. Nanotechnology in Civil Infrastructure: A 37

Paradigm Shift. Springer, 2011. 38 6) Henderson V. Evaluation of the Performance of Pervious Concrete Pavement in the Canadian 39 Climate. PhD Thesis presented in Waterloo, Ontario, Canada, 2012. 40

7) Kevern, J., Wang, K., Suleiman, M.T., and Schaefer, V.R. Pervious Concrete Construction: 41 Method and Quality Control. Submitted to NRMCA Concrete Technology Forum: Focus on 42 Pervious Concrete, May 24-25, 2006, Nashville, TN. 43 8) Michael, J. Gibbs, Peter S., David, C., CO2 emissions from cement production. Good Practice 44 Guidance and Uncertainty Management in National Greenhouse Gas Inventories. 45


9) Bushi, L., Jamie M., An Environmental Life Cycle Assessment of Portland-Limestone and 1

Ordinary Portland Cements in Concrete. Prepared for Cement Association of Canada, January 2 2014. 3 10) Bjorn, B., Anal, K. M., Georgene, G., Mohammad, K., Konstantin, S., Transportation 4

research Circular, Number E-C170: Nanotechnology in concrete materials, a synopsis. 5 Transportation Research Board of the national Academies, December 2012. 6 11) Russel, Peter. Concrete admixtures. 1983. 7 12) Gonzalez, M., Lima, A., Tighe, S. L. Abrasion Response for Nanoconcrete for Rigid 8 Pavements and its Impacts on Friction. Submitted for Presentation at the 93

rd TRB Annual 9

Meeting and Publication in the 45th

Transportation Research Record: Journal of the 10 Transportation Research Board. 11 13) American Society for Testing and Materials (ASTM). Standard Test Method for Density and 12 Void Content of Freshly Mixed Pervious Concrete. ASTM C1688/1688M-12. ASTM 13

International, Philadelphia, U.S.A., 2012. 14 14) American Society for Testing and Materials (ASTM). Standard Practice for Making and 15

Curing Concrete Test Specimens in the Laboratory. ASTM C192/192M-13a. ASTM 16 International, Philadelphia, U.S.A., 2013. 17

15) American Society for Testing and Materials (ASTM). Standard Test Method for 18 Compressive Strength of Cylindrical Concrete Specimens. ASTM C39/39M-12. ASTM 19 International, Philadelphia, U.S.A., 2012. 20

16) American Society for Testing and Materials (ASTM). Standard Test Method for Abrasion 21 Resistance of Concrete or Mortar Surfaces by the Rotating-Cutter Method. ASTM C944/944M-22

12. ASTM International, Philadelphia, U.S.A., 2012. 23 17) American Society for Testing and Materials (ASTM). Standard Test Method for Flexural 24

Strength of Concrete (Using Single Beam with Third-Point Loading). ASTM C78/78M-101

. 25 ASTM International, Philadelphia, U.S.A., 2010. 26

18) Tennis, D. Paul, Leming, L. Michael, Akers, J. David. Pervious Concrete Pavements. 27 Portland Cement Association. 2004. 28 19) Kreyszig, E. Introductory Mathematical Statistics-Principles and Methods. 1970. 29

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