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Diploma Engineers’ Association
नि�र्मा��ण सुपरी�वे�क्षण तथा� गुणस्तरी नि�यन्त्रण
Construction Supervision andQuality Control
Rajendra P. Adhikari, Ph. D.20 Dec 2014 (5 Poush 2071)
Birganj,Nepal
2
नि�र्मा��णर्मा� प्रत्यक्ष सु�लग्� पक्षहरु
Employerनि�य�क्ता�
Consultant/Engineer
कन्सुल्टे�न्टे/ईन्जिन्%नि�यरी
Contractorनि�र्मा��ण व्यवेसु�य�
Development Partnersदा�त( नि�क�य
Suppliers/Sub-contractors
आप*त+कत��/सुवे-कन्ट्रा�क्टेरी
3
क� ह� अ�भवेहरु बाँ�1डौं3
• नि�र्मा��ण का�र्य�सं�ग संम्बन्धि�त नि�र्य�क्ता�का� का�रण नि�र्मा��णस्थलर्मा� दे�खि��� का� �� त�� निबषर्य/संन्देर्भ�हरु बत�उ��ह�सं$
• नि�र्मा��ण का�र्य�सं�ग संम्बन्धि�त पर�र्मार्श�दे�त� वा� इन्जिन्*नि�र्यरका� का�रण नि�र्मा��णस्थलर्मा� दे�खि��� का� �� त�� निबषर्य/संन्देर्भ�हरु बत�उ��ह�सं$
• नि�र्मा��ण का�र्य�सं�ग संम्बन्धि�त नि�र्मा��ण व्यवासं�र्य�का� का�रण नि�र्मा��णस्थलर्मा� दे�खि��� का� �� त�� निबषर्य/संन्देर्भ�हरु बत�उ��ह�सं$
4
नि�र्मा��णर्मा� सु�लग्� पक्षहरुक� भ*मिर्माक�नि�य�क्ता�
• य�%��क� छ�6टे• प7सु�क� %�ह�
कन्सुलटे�न्टे/ ईन्जिन्%नि�यरी• आय�%��क� निडौं%�इ�• सुपरिरीवे�क्षण तथा� गुणस्तरी नि�यन्त्रण
नि�र्मा��ण व्यवेसु�य�
• नि�र्मा��ण क�य� • स्पे�शि<नि=क� <� अ�सु�री री आय�%�� हस्त�न्तरीण
दा�त( नि�क�य
•निबाँक�सुक� ल�गु� आवेस्यक ऋण/अ�दा��क� व्यवेस्था� गु�@
आप*त+कत��/सुवे कन्ट्राकक्टेरी •नि�र्मा��ण सु�र्मा�ग्री� आप*त+ गु�@ तथा� सुवे कन्ट्रा�क्टेर्मा� क�र्मा गु�@
आय�%�� व्यवेस्था�प� क� ह� री कसुरी� गु�@?
5
आय�%�� व्यवेस्था�प�क� प्रर्माख तत्वेहरु
6
सुर्माय
गुणस्तरी ल�गुत
आय�%�� व्यवेस्था�प�क� चु�6त�हरु
• स्रो�त र सं�र्मा�ग्री�का� उचि/त परिर/�ल�• नि�र्मा��ण लक्ष प�र� ग�� स्रो�त र सं�र्मा�ग्री�का� एनिकाका3 त व्यवास्थ�प� ग���• त�निकाएका� संर्मार्यभिर्भत्रै� का�र्मा संम्पन्� ग���• त�निकाएका� ल�गतभिर्भत्रै का�र्मा संम्पन्� ग��� र• त�निकाएका� ग�णस्तर का�र्यर्मा ग���
7
आय�%�� अ�गुर्मा� चुक्र
8
क�य� य�%�� बाँ��उ��
प्रगुनित अ�गुर्मा� गु�@
=रीक अबाँस्था� र्मा�प�
गु�@/नि�न्जिFचुत गु�@
प्रगुनित प्रनितवे�दा� तय�री प��@ री
बाँझा�उ��
आवेस्यकत� अ�सु�री क�य�
य�%��र्मा� <�सु�ध� गु�@
ह�र्मा�ल� क� गु�� ख�%�क� ह� ? सुबाँ7ल� बाँझ्�� ढं�गुल� बाँ��उ��
सु�इटेर्मा� कनित क�र्मा भएक� छ? ��प्�� री सु� क�
निवेवेरीण %म्र्मा� प��@
क�य� य�%�� री प्रगुनितक� बाँ�चुर्मा� कत्ती�क� =रीक परी�क� छ पत्ती�
लगु�उ��
सु�इटेबाँ�टे प्र�प्त निवेवेरीण अ�सु�री प्रगुनित/नि�री�क्षण प्रनितवे�दा� तय�री प��@ री बाँझा�उ��
आय�%�� नि�यन्त्रणक� पक्षहरु
• संर्मार्य (Schedule)• ल�गत (Budget), तथा�• ग�णस्तर (Specification)
9
Time performance
Costperformance
Qualityperformance
क�य� य�%�� बाँ��उ� प्रय�गु गुरिरी�� सु�ध�हरु
1. Gantt chart, Linked bar chart and milestones chart
2. CPM/PERT3. Earned Value Analysis
10
Gantt chartबाँ�री चु�टे�
S. No.
Activities 1 2 3 4 6 7 8 9 10
1 Tender document preparation
2 Tender document issue
3 Tender document submission
4 Tender evaluation
11
Linked bar chartलिलङ्Q क बाँ�री चु�टे�
S. No.
Activities 1 2 3 4 6 7 8 9 10
1 Tender document preparation
2 Tender document issue
3 Tender document submission
4 Tender evaluation
12
लिलङ्Q कहरु
Milestones chartर्मा�इलस्टे�� चु�टे�
S. No.
Activities 1 2 3 4 6 7 8 9 10
1 Tender document preparation
2 Tender document issue
3 Tender document submission
4 Tender evaluation
13
र्मा�इल स्टे��हरु
Network diagram
14
Source: Construction Management, Rajendra P. Adhikari
PERT
15
The optimistic (आसु�बाँ�दाR) time estimate (Ote)The pessimistic (नि�री�सु�बाँ�दाR) time estimate (Pte)
The most likely (बाँढंS सु�भवे हु��) time estimate (Mlte)Expected (सु�चु�क�) time (Te)
Expected time
Te = Ote + 4Mlte + Pte 6
16
Exampletell me:(a) if every thing progress as you expect, say in
complete ideal situation how long it will take?
(b) if every thing goes wrong and encountered unexpected situations, say in worst condition how long it will take? And
(c) in carrying out such work what would be the normal duration?
17
Let’s say: in first case, the time required would be 10 weeks in second case 34 weeks, and in third 16 weeks.
18
The Expected Time
10 + (4 x 16) + 34te = 6
= 18 weeks
19
Cost optimizationImportance of time-cost analysis
(Gahlot & Dhir, 1992)
• क �7 आय�%��क� अवेलिध कनितसुम्र्मा छ�टेQय�उ� सुनिकन्छ ?
• आय�%��क� अवेलिध सुबाँभन्दा� कर्मा खचु�र्मा� कनितसुम्र्मा छ�टेQय�उ1� सुनिकन्छ ?
• आय�%��क� क � चु�1ह� अबाँलिधर्मा� सुर्माग्री आय�%��क� खचु� सुबाँभन्दा� कर्मा हुन्छ ?
20
आय�%��क� ल�गुत1. Direct cost (प्रत्यक्ष खचु�)-
labor, material, equipment costs
2. Indirect cost (अप्रत्यक्ष खचु�)
- insurance charge, administration charges etc.
21
अबाँलिध/सुर्माय अ�सु�री ल�गुतर्मा� दा�खिख�� शिभन्�त�
22
Descriptions Work days
Rate/day (Rs.)
Total (Rs.)
1 man working 1 shifts 6 200 1200Man working 2 shifts/day for 3 daysAdditional Rs. 50 for 2nd shift(200 + 250 = 450)1st day Rs.
3 450 1350
Man working 3 shifts/day for 2 daysAdditional Rs. 50 for 2nd shift; 100 for 3rd shift(200 + 250 + 300= 750)1st day Rs.
2 750 1500Any number of men working but duration
cannot be reduced beyond 2 days
Variation of direct cost with time
23
Cost (Rs.)
Rs. 500
Rs. 1000
Rs. 1500
Rs. 2000
2 4 6
Crash time Normal time
Crash cost
Normal cost
Cost slope
Normal time: performing an activity with the normally available resources.Normal cost: minimum direct cost; while performing in normal time duration.Crash time: minimum time in which activity can be performed.Crash cost: direct cost corresponding to the crash time.
24
Variation of indirect cost with time
25
Cost (Rs.)
Time
Cost optimization
26Time (Days)
Cost (Rs.)
Direct cost
Indirect cost
Total cost
Optimal time
Optimal cost
Earned Value Analysis (EVA)• Budgeted cost of work scheduled (त�निकएक�
क�र्मा सुम्पन्� गु�� ल�गुत अ�र्मा��/बाँ%�टे अ�सु�रीक� खचु�) (BCWS)
• Budgeted cost of work performed, which is also called Earned Value (सुम्पन्� गुरिरीएक� क�र्माक� ल�गुत अ�र्मा��/बाँ%�टे अ�सु�रीक� खचु�) (BCWP)
• Actual cost of work performed (सुम्पन्� गुरिरीएक� क�र्माक� बाँ�स्तनिवेक खचु�) (ACWP)
27
0
200
400
600
800
1000
1200
1400
1600
1800
2000
1 3 5 8 10 11
Time for BCWS
BCWP
ACWP
Cost Variance (CV)
28
Cost variance (CV) is the difference of Budgeted Cost of Work Performed (earned value) minus Actual Cost of Work Performed. It can be expressed as:
CV = BCWP – ACWP, where negative variance indicates cost overrun
0
200
400
600
800
1000
1200
1400
1600
1800
2000
1 3 5 8 10 11
Time for BCWS
BCWP
ACWP
Schedule Variance (SV)• Similarly, schedule variance (SV) is the
difference of Budgeted Cost of Work Performed (earned value) minus Budgeted Cost of Work Scheduled. It can be expressed as:
• SV = BCWP – BCWS, where negative variance indicates time overrun.
29
0
200
400
600
800
1000
1200
1400
1600
1800
2000
1 3 5 8 10 11
Time for BCWS
BCWP
ACWP
Cost performance (CP)
Cost performance can be obtained by multiplying earned value (BCWP) by Actual Cost of Work Performed (ACWP), which can be expressed as:
30
BCWPCP =
ACWP
0
200
400
600
800
1000
1200
1400
1600
1800
2000
1 3 5 8 10 11
Time for BCWS
BCWP
ACWP
Schedule performance (SP)
Schedule performance can be obtained by multiplying earned value (BCWP) by Budgeted Cost of Work Scheduled (BCWS), which can be expressed as:
31
BCWPSP =
BCWS
Example(Adhikari (2004), Construction Management)
• 50 units of plantation have to be done in 2 weeks period.
• Estimated plantation cost was Rs. 200/unit• Progress monitoring was done one week
after the work was completed • Only 40 % work was completed (as per
schedule 50 % has to be completed)• Actual cost was Rs. 250/unit
32
Here,• BCWS: 25 x 200 = Rs. 5000• BCWP: 20 x 200 = Rs. 4000• ACWP: 20 x 250 = Rs. 5000
33
Cost variance (CV)ल�गुतर्मा� शिभन्�त�
• CV = BCWP – ACWP• = 4000 – 5000 = - 1000
• CP = BCWP/ACWP 4000/5000 = 0.80Here, Total cost would be (50 units x Rs. 200)/0.80
= Rs. 12500
34
Schedule variance (SV)त�लिलक�र्मा� शिभन्�त�
• SV = BCWP – BCWS 4000 – 5000 = - 1000
SP = BCWP/BCWS 4000/5000 = 0.80
Here,Total completion time would be
2 weeks/0.80 = 2.5 weeks 35
Cost control (Budget control)ल�गुत नि�यन्त्रण
ल�गुत नि�यन्त्रण यह�1दा�खिख �7 <रु हुन्छ …
• Preparation of cost estimate (PPA 5)• Preparation of procurement plan ( PPA 6)• Selection of procurement method (PPA 8) • Price adjustment (PPA 55) • Arrangement of budget and construction site
(PPR 6)
36
Cost control ल�गुत नि�यन्त्रण
• Payment Certificates• Payments• Compensation Events• Tax• Currencies• Price Adjustment• Retention• Liquidated Damages• Bonus
37
Advance Payment Securities Day works Cost of Repairs
Quality Controlगुणस्तरी नि�यन्त्रण
• त्रै�टी: (Defects) पत्ता� लग�उ��• पर�क्षण ग�< (Tests)• त्रै�टी: सं�धा��< (Correction of
Defects)• �सं�धा�रिरएका� त्रै�टी:हरु (Uncorrected
Defects)
38
39
Technical Specificationप्र�निबाँलिधक स्पे�शि<नि=क� <�
• A technical specification is the generally accepted standard for construction specifications.
• It is considered best because it completely details the exact need or condition to be met.
• It requires the construction supervisor to account for every detail leaving little if nothing to chance.
• The challenge is to have a construction supervisor who is familiar with every detail of the construction process.
Documentationरी�कडौं� री�ख्��
• Daily Record Keeping• Daily Construction Report – date, project
name, location, weather condition (temperature, cloud, precipitation), meetings & decisions, record of visitors at site
• Location of construction underway• Sub-contractor, Personnel and equipment
working in each activity
• Descriptions of works being inspected• Decisions made regarding approval of materials
or of work, and corrective actions taken• Descriptions of problems or delays and resolution• Communication with contractor staff• Construction activities completed and/or
progress• Progress photos (where applicable)• Signature of the report preparer
41
• Inspecting and testing report format• Record drawings• Control of quality records• Daily construction QA logs and records• Inspection checklists and reports• Non-conformance reports• Material receiving reports, and• Monitoring and test data
42
गुणस्तरी नि�यन्त्रण
What is Quality?
• स्पे�चिर्शनि?का� र्श�र्मा� उल्ल�� र्भए अ��सं�रका� का�र्मा नि�र्मा��णस्थलर्मा� हु�� वा�
• स्पे�चिर्शनि?का� र्श�र्मा� उल्ल�� र्भए अ��सं�रका� नि�र्मा��ण का�र्य� हु��
Burj Dubai• Over 800 metres
(2625 feet) • More than 160
stories• Tallest building in
the world• Tallest free-standing
structure in the world
Project management specific/RPA_17.12.2009 45
Burj Dubai Construction Timeline
January 2004 Excavation started
February 2004 Piling started
March 2005 Superstructure started
January 2010 Official launch ceremony
46
Project management specific/RPA_17.12.2009 47
Dubai in 1990
The same street in 2003
Dubai in 2007
Dubai Downtown
48
Pyramid City in the Air(SHIMIZU CORPORATION)
49
• The Shimizu TRY 2004 Mega-City Pyramid is a proposed Shimizu Corporation project for the construction of a massive pyramid over Tokyo Bay in Japan.
• The structure would be more than 14 times as high as the Great Pyramid of Giza
• It would house 1,000,000 people.
50
• The structure would be 2000 meters (6,561 feet) tall measured from mean sea level
• This pyramid would help answer Tokyo's increasing lack of space
• The proposed structure is so large that it could not be built with current conventional materials, due to their weight.
• The design relies on the future availability of super-strong lightweight materials based on carbon nanotubes presently being researched.
What May be Quality?Japanese and American Business Deal)
• It may mean Zero Defects, an idea perfected by Japanese manufacturers who refuse to tolerate defects of any kind.
• US companies operated according to the premise of Acceptable Quality Level (AQL)
Difference in Attitude
• The difference between Acceptable Quality Level (AQL) and Total Quality Management (TQM) is the attitude toward quality.
• AQL says quality is characteristics of a product that meets or exceeds engineering standards.
• TQM says that quality is that quality of a product, which is so good that the customer would not think of buying from anyone else.”
What is Quality Assurance?
• Quality assurance, or QA refers to a program for the systematic monitoring and evaluation of the various aspects of a project, service, or facility to ensure that standards of quality are being met.
• Two key principles characterize QA: "fit for purpose" (the product should be suitable for the intended purpose) and "right first time" (mistakes should be eliminated).
• It is important to realize also that quality is determined by the intended users, clients or customers.
• QA is more than just testing the quality of aspects of a product, service or facility, it analyzes the quality to make sure it conforms to specific requirements and comply with established plans.
Steps for Quality Assurance Process
• Test previous article• Plan to improve• Design to include improvements and
requirements• Manufacture with improvements• Review new item and improvements• Test new item
Quality assurance vs.quality control
• Quality control emphasizes testing of products to uncover defects, and reporting to management who make the decision to allow or deny the release
• Quality assurance attempts to improve and stabilize production, and associated processes, to avoid, or at least minimize, issues that led to the defects in the first place.
• To prevent mistakes from arising, several QA methodologies are used.
• QA does not eliminate the need for QC: some product parameters are so critical that testing is still essential.
• QC activities are treated as one of the overall QA processes.
Elements of Quality Management System
• Organizational Structure• Responsibilities
• Procedures• Processes• Resources
• Customer Satisfaction• Continuous Improvement
Total Quality Management (TQM)
• Total – made up the whole• Quality – Degree of excellence a product or
service provides• Management – Act, art or manner of
handling, controlling, directing etc.
58
TQM Basic approach
1. A committed management2. Focused on customer3. Involvement and utilization of the total work
force4. Continuous improvement5. Treating suppliers as partners6. Establish performance measures for each
components/ persons
59
6. Bench marking7. Information technology8. Quality management systems9. Environment management system10.Quality function deployment (Customer
requirements led design)
60
11. Quality by design12. Failure mode analysis (Reliability)13. Product liability14. Total productive maintenance15. Management tools16. Statistical process control
61
ResponsibilitiesContractor responsibility
• Contractors are responsible for all activities necessary to manage, control and document work so as to ensure compliance with the contract plans and specifications.
62
Quality Control Requirement
• Contract clause :– Identifying defects (The PM)– Tests (The PM)– Correction of defects (The Contractor/PM)– Uncorrected defects (The PM)
63
Therefore QC and QA ?
• QC is the system established by the Contractor for achieving the quality as indicated in the drawing and/or specifications.
• QA should be the system of the Public Entity for assurance of that the quality will be achieved by the end of the project.
64
Contractor’s Responsibility
• In general contractor is responsible for all the activities necessary to ensure the achievement of the contract quality:– Contractors’ organization– Staff– Suppliers– Subcontractors
65
Public Entity’s Responsibility
• Review of the plans and specifications for:– Constructability– Operability, and– Environment compliance
66
Pre-construction activities
1. Prepare a written QA organizational operating plan (at the center level)
2. Review the site plan (field office)3. Review the work loads at the site and
determine the staffing needs4. Ensure that the staffs have a clear
understanding of QA/QC responsibilities5. Identify training needs, design and provide
training67
6. Review contractor’s QC plan and check the following:
• Does the QC plan adequately cover all features of the contract?
• Is the qualified QC staff adequately planned to maintain quality and conduct the tests?
• Has responsibility & authority rightly allocated to each staff?
• Is the channel of information flow rightly designed?• Review the lab setting for its appropriateness for required
tests• Are the definable components are rightly identified e.g. for
concreting work- formwork, reinforcing and other items, placement of concrete, mix design, etc.
• Accept the QC plan submitted by the contractor with subject to revision
68
Implementation1. Conduct coordination meeting with the contractor (by the RE)
for implementation of accepted QC/QA plan and prepare minutes of the meeting including the signature of the RE/PC/TL and the Contractor.
2. Verify test labs and or lab arrangement including its calibration
3. Spot check the contractors submittals4. Review the contractors daily QC reports5. Hold meetings at regular intervals6. Monitor for the contractor’s work procedures for tracking
construction defects/deficiencies7. Maintain record (well documentation)8. Be confirm that necessary “control” has been adopted 69
Guidelines for preparing QA Plan
• Identification of the activities and grouping them based on their criticality/importance
• Prepare inspection schedule• QC test schedule• Reporting process and formats• Define authority for control• Define process for correcting defects• Schedule meetings with contractor• Provide assistance as well as training• Define responsibility center
70
Check list to Control Quality (Example)
S. No. Activity When(Yes)
Who(No)
1 Set out and maintain records of surveying and bench marks
Date Name
2 Inspect and review contractors facilities at site
3 Maintain monthly meeting records
4 Inspect and review contractors survey and layout of works
5 Inspect and review contractors test procedures and reports
6 Inspect and review manufacturer’s production process
7 Inspect and review the equipment mobilized at site
71
Quality Assurance Programs Involve:
• Site office planning• Preparation of QA plan• Review of QC plan• Following and enforcing
CoC• Inspection• Documentation, and • Acceptance of the
works after completion
72
ExerciseQuality assurance plan
Activity/ material
Activities involved/ special features
Inspection/test required
Frequency and dates
Who is responsible for inspection/test report preparation
Who is responsible for control
Water quality at sourceWater quality at outlet of the reservoirWater quality at the tap of the user
73
PDCA Cycle
74
Plan Do
Act Check
75
धन्यबाँ�दा