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  • 1. 109 First International Conference on Construction In Developing Countries (ICCIDC–I) “Advancing and Integrating Construction Education, Research & Practice” August 4-5, 2008, Karachi,, Pakistan Quality Assurance and Control in the Construction of Infrastructure Services in Developing Countries – A Case Study of Pakistan Ammad Hassan Khan Assistant Professor, Department of Civil Engineering, University of Engineering and Technology, Lahore, Punjab, Pakistan ammadhk@hotmail.com Salman Azhar Assistant Professor,McWhorter School of Building Science, Auburn University, Auburn, Alabama, USA Arshad Mahmood Engineer,DESCON-CGGC(JV), Lahore,Punkab, Pakistan Abstract Quality is one of the critical factors in the success of construction projects. Quality of construction projects, as well as project success, can be regarded as the fulfillment of expectations (i.e. the satisfaction) of the project participants. The construction industry in Pakistan has been struggling with quality issues for many years. The construction costs can be significantly reduced if the construction industry embraces the concept of quality assurance and control that has been used with great success by service and manufacturing industries in Pakistan. However, unlike manufacturing and service industries, where a standard product is regularly produced, most products of the construction industry are one-offs, specially designed for a specific purpose. Hence, attainment of a quality level is difficult both to specify and to monitor. In this paper, a case study of the quality assurance and control during the execution of Taunsa Barrage Emergency Rehabilitation and Modernization Project contract packages ICB-01 (Sub-weir, downstream floor of barrage, instrumentation) has been presented. The Taunsa Barrage Project has been considered as a success story in the construction of infrastructure development projects in developing countries. The major part of the civil works of the Taunsa Barrage Project has been completed. This paper is focused on the quality assurance and control using the concept of quality, quality management system (QMS) and quality management system standards in the civil construction works. Keywords Quality, Quality Assurance, Quality Control, Civil Works, Infrastructure Projects 1. Introduction Quality is a desirable characteristic by all stakeholders in construction. The quality assurance (QA) is a set of activities whose purpose is to demonstrate that an entity meets all quality requirements (ISO, 2007). QA activities are carried out in construction projects to inspire the confidence of stakeholders in meeting the quality requirements. QA provide the stakeholder with adequate confidence that a structure, component, material or system meets pre-stated quality standards and will perform satisfactory during its entire service life. Quality control (QC) is the set of activities or techniques whose purpose is to ensure
  • 2. 110 that all quality requirements are being met. In order to achieve QC, processes are monitored and performance problems are solved (ISO, 2007). Quality Control (QC) is concerned with actual measurement, testing or supervision of manufacturers’ own final product control, either by inspection of each unit or by sample testing. Originally a manufacturing-industry concern, quality is now acknowledged to be a key issue for the construction sector whose clients increasingly demand quality certification (Chung, 2007). The objective of construction QA/QC is to independently assure that the activities of a specific project are being performed in accordance with all contractual specifications, codes and standards or government regulations. The QA/QC is verified through checks audits, inspections and witnessing. These audit services are carried out completely independently of the individual contractors, materials suppliers, manufacturer or sub contractor as well as the purchaser or final user. Quality Assurance (QA) provides the facility owner with adequate confidence that a structure, component, material or system meets pre-stated quality standards and will perform satisfactory during service. QA/QC inspections can be applied to all materials, structures, components or systems utilized in the construction and operation of complex industrial plants including nuclear power stations. This service is being provided both on the construction site and at the facilities of the manufacturers involved. The choice of operations to be performed depends on the requirements of the assignment. Project quality management must address both the management of the project and the product of the project. Failure to meet quality requirements in either dimension can have serious consequences for any or all the project stakeholders (PMI, 2000). The quality conscious construction stakeholders believe that the essence of true QA/QC is in constant inspection along with project quality teams having a deep knowledge of the QA/QC procedures. The verifications and reminders of quality in construction stakeholders are consistently communicated from upper management to superintendents. In order to accomplish the expectations from subcontractors, the main contractors must inspect their work on a regular and consistent basis, with corrections made well before punch list reviews. A case study of the quality assurance and control during Taunsa Barrage Emergency Rehabilitation and Modernization Project, the oldest headwork of Southern Punjab, Pakistan has been discussed in this paper. Taunsa Barrage (as shown in Figure 1) was originally constructed in a period of five years from 1953 to 1958 over the Indus River in the Southwest part of Punjab in Kot Addu Tehsil of Muzaffargarh District. Soon after it's commissioning, it experienced multiple engineering problems, which aggravated with the passage of time. Taunsa Barrage facilitates the flow of irrigation water from the Indus River in three major canals, Muzafar Garh Canal (8,300 cusecs), Dera Ghazi Khan Canal (89,000 cusecs) and Taunsa Panjnad (T-P) Link Canal (12,000 cusecs) supplying some six million acre feet of irrigation water to cultivated lands in districts of Muzafagarh, Rajanpur, Rahim Yar Khan and Bahawalpur during Rabi and Kharif agricultural seasons. The purpose of this rehabilitation project is to prevent the breaking down of the dilapidated Taunsa Barrage. The project comprises of the restoration of the barrage, floodgates and its incidental facilities in order to guarantee a water resource to the peripheral area. Samples of surface water as well as ground water have been collected, tested and analyzed for physical, biological and chemical elements in order to determine its suitability for aquatic flora and fauna, irrigation purposes as well as human consumption.
  • 3. 111 Figure 1: Taunsa Barrage It is important to note that all the barrages operating in Punjab have depreciated primarily due to age. To adequately address this issue, Government of Punjab has successfully negotiated a loan from the World Bank towards the cost of rehabilitation and modernization of Punjab barrages (Descon News, 2005). Out of the entire construction cost of US$150 million, the World Bank is financing US$123 million (approved in October 2004). Also, the Government of Japan is contributing a grant aid of 5,165 million yen, for the detailed design of floodgates and these have been executed by JICA. The client of the project is Government of Punjab through Project Monitoring Organization (PMO) of Irrigation and Power Department. The design and supervision consultants of the project are Punjab Barrages Consultants (A Joint Venture of National Drainage Consultants (NDC), National Engineering Services of Pakistan (NESPAK) and Atkins-UK). The contractors for the ICB-01 package are joint venture between Descon Engineering Limited and China Gezhauba Water and Power Group Company (CGGC). The Contractors for ICB-01 package is M/s CCC of China. All the major contractors and consultants of the project are ISO certified organizations. 2. Quality Assurance and Control at Taunsa Barrage Rehabilitation and Modernization Project According to Hendrickson (1999), the quality requirements should be clear and verifiable, so that all parties in the project can understand them for conformance. In Taunsa barrage project, the Engineers’ Quality Assurance Program (EQAP) in compliance with ISO 9000/2000 quality management system (QMS) has been used. The references for the quality system are as follows: • General conditions of contract part 1 (FIDIC) clause 36 & 37 about materials, plant and workmanship. • SP-9 Approval of materials and equipment (Source approval and approval on site). • SP-10 Contractor’s quality assurance plan. The on and off site QA/QC activities included in the Taunsa barrage rehabilitation and modernization project are listed in Table 1. Table 1: Taunsa Barrage Rehabilitation and Modernization Project Quality Management System Sr. Description Activity 1 OnSiteQA/QCTasks Audit of the QA programs of the organizations involved in the construction and/or operation of the facility, including personnel qualifications and QA manuals. 2 Review of the specifications, procedures and specified standards utilized on the construction site. 3 Monitoring the control of construction materials. 4 Performance of on-site surveillance covering non-destructive testing, visual testing, hydrostatic and performance testing of installations and equipment. 5 Monitoring the storage methods and preventive maintenance system of plant equipment before and during installation. 6 Organization and implementation of record retention systems and the development of accompanying procedures that are practical, logical and meet the requirements of regulatory agencies.
  • 4. 112 Sr. Description Activity 1 OffSiteQA/QCTasks Assistance in defining the QA program which meets the full intent of all regulatory requirements. It includes aspects of organization, personnel, inspection plans and program, and procedures. This is summarized in QA manual. 2 Review of the design, specifications, drawings and specified standards to assure compliance to the applicable regulatory requirements. 3 Performance of pre-award or pre-qualification surveys including a complete review of the suppliers QA program to meet governmental or purchaser’s requirements. 4 Inspection, witnessing or verification of any action undertaken during manufacture to establish the quality of a material, structure or system. These functions are accomplished in accordance with requirements of QA standards and government regulations. 5 Assistance to the purchaser in cases where corrective action is needed due to non-conformity. 6 Assistance in public hearings and standard review boards. 7 Performance of formal audits before and during the manufacture of equipment at the premises of the architect, constructor, manufacturer or sub-supplier. 8 Organization of training courses in such fields as QA, reliability, test methods, equipment and plant systems and related quality areas such as safety, and the qualification and certification on non-destructive testing / evaluation methods. The details of the quality management system of Taunsa barrage rehabilitation and modernization project are shown in Figure 2. Figure 2: Taunsa Barrage Rehabilitation and Modernization Project Quality Management System)
  • 5. 113 The project quality management system (QMS) was very comprehensively formulated. However, these PQMS is not addressing any limits or margins of acceptability in case of onsite and offsite Q.A/Q.C tasks. The contractor of the project especially remained in excessive pressure due to the unlimited exercise of the PQMS implementation on the project by Client and Consultant. It has been observed in the project that excessive strictness in the implementation of the quality sometimes originate various crucial technical constraints, which seriously affect the scope, schedule and budget. It has also been depicted from the project case study that in case of excessive experimentation related to the quality in the projects (when the technical quality related background of the stakeholders is also limited), number of times the project stakeholders were unable to get any favorable solution. The documentation controlling based on the project PQMS comprise of following: Changes in construction processes Material procurement Field testing and inspection Final check out of facility The process and implementation of the Q.A/Q.C audit procedures always remain difficult to apply in the developing countries infrastructure projects. The same difficulties have been observed in the subject project. These difficulties has been arising various questions and doubts in the direction, communication, integration and outcomes of the quality management system of the project. Thus the development of an integrated project oriented quality management system for the project is necessary for Client and important from the ISO9000:2000 perspective. So in the subject project after the implementation shortcomings of PQMS, an advance version of the PQMS in the form of project oriented quality management system has been established. This system has provided support and removes the discrepancies in the quality consequences. The representation procedure of the system is shown below in Figure 3. Figure 3: Project Oriented Quality Management System PQMS data for Client Client Consultant Sub-Contractor PQMS data for Consultant PQMS Data for Contractor Contractor Project Oriented PQMS Data ProjectOrientedPQMSData
  • 6. 114 The various project site activities related to QA/QC are shown in Figure 4. Figure 4: Site Photographs
  • 7. 115 2.1 Material Sources Approval The major scope of work in the project includes the reinforced cement concrete (RCC), steel sheet piles and earthwork. Thus the approved sources in-context with quality management system have been required for steel, cement, fine aggregates, coarse aggregates, slag, additives, water stops, and steel sheet piles. The quality management standards adopted for the approval of the sources of material are listed in Table 2. The references for the quality management standards of materials have been mainly adopted from the American Standards for the Testing of Materials (ASTM, 2007). The Pakistan standards & quality control authority (PQSA, 2007) guidelines for the selection of material quality and sources have also been incorporated wherever necessary in this project. Table 2: Taunsa Barrage Rehabilitation and Modernization Project Materials with Quality Management Standards, Tests and Approved Sources Sr . Material Quality Management Standards Quality Tests Approved Sources 1 Steel Reinforce- ment ASTM-615-81 (a) Yield strength, ultimate strength, percentage elongation, bend test, diameter, weight and x-area. Fazal (FSL, 2008) and Pak Steel (PAK, 2008) 2 Cement ASTM C-204, 109,187,191, 151,BS-12, PSS- 232:1983(R) Blain air permeability, compressive strength, normal consistency, initial & final setting time, soundness, Le-Chatlier expension, loss of ignition, silicon oxide, insoluble residue, alumina, iron oxide, calcium oxide, magnesia, sulphur trioxide. Askari(Askari, 2008), Mapple Leaf(KMLG,2008), DG Khan(DGK,2008) and Javedan (JCL,2008) 3 Coarse Aggregates ASTM C-136, 117,29,127, 566,81,131, 142,123,295, 227 Sieve analysis, material passing # 200, unit weight, specific gravity, absorption, moisture content, soundness, Loss Angeles Abrasion, clay lumps and friable particles, petrography, mortar bar test for potential alkali reactivity. Sakhi- Sarwar, Saanghar and Vehao 4 Fine Aggregates ASTM C-136, 117,29,128,56 6,88,142,2419 , 40,123,295, 227 Sieve analysis, material passing # 200, unit weight, specific gravity, absorption, moisture content, soundness, clay lumps and friable particles, sand equivalent, organic impurities, light weight particles, petrography analysis, mortar bar test fro potential alkali reactivity. Khumbi and Kohar 5 Slag ASTM C-150 Type IV Silicon oxide, alumina, iron oxide, calcium oxide magnesia, sulphur tri- oxide, Blain air permeability, residue, 7- 28 days slag activity index Attock cement and Thatta cement 6 Additives Manufacturer Specified Chemical and physical properties Sika and Fosroc 7 Water Stops Manufacturer Specified Chemical and physical properties Decora 8 Sheet Piles ASTM A-857, 328 Mill test, heat analysis and tensile test. Arcelor
  • 8. 116 The quality control has been achieved through assurance of the specifications, QC manual, monitoring, inspection, testing, measuring testing equipments, testing, test results, non-conformance reports & actions, QC records and internal quality audits. 2.2 Testing Frequency for the Major Materials The testing frequency for the major construction materials is listed in Tables 3(a)-(g). Table 3(a): Testing Frequency for Soil Materials Sr. Test Designation Testing Frequency 1 Grain Size Analysis/Gradation ASTM C-136 & D-422 1 per 10,000 cft 2 Hydrometer ASTM D-442 1 per 50,000 cft 3 Liquid Limit ASTM D-4318 1 per 50,000 cft 4 Plastic Limit ASTM D-4318 1 per 50,000 cft 5 Shrinkage Limit ASTM D-427 1 per 50,000 cft 6 Specific Gravity ASTM D-854 1 per 50,000 cft 7 Moisture Density Relationship ASTM D-1557 1 per 50,000 cft 8 Moisture Density Relationship ASTM D-698 1 per 50,000 cft 9 Field Density: Compacted Fill ASTM D-1556 1 per 20,000 cft 10 Field Density: Structural Back fill ASTM D-1556 1 per 2,000 cft 11 Field Density: Gravel Base ASTM D-1556 1 per 5,000 cft 12 Relative Dry Density ASTM D-4253 & 4254 1 per 5,000 cft Table 3(b): Testing Frequency for Cement Sr. Test Designation Testing Frequency 1 Compressive Strength ASTM C-348 & C-349 1 per 200 tons or 1 per month if consumption is < 200 tons 2 Initial and Final Setting Time (on Pure Past) ASTM C-191 1 per 200 tons or 1 per month if consumption is < 200 tons 3 Autoclave Expansion ASTM C-151 1 per 200 tons or 1 per month if consumption is < 200 tons 4 Blaine’s Specific Surface Area ASTM C-204 1 per 200 tons or 1 per month if consumption is < 200 tons 5 Chemical Analysis ASTM C-114 1 per 1000 tons or 1 after 3 months if consumption is < 1000 tons Table 3(c): Testing Frequency for Steel Sr. Test Designation Testing Frequency 1 Size and weight ASTM A 615 As Required 2 Elongation ASTM A 615 As Required 3 Bending test ASTM A 615 As Required 4 Tensile strength and yield strength ASTM A 615 As Required
  • 9. 117 Table 3(d): Testing Frequency for Fine Aggregates Sr. Test Designation Testing Frequency 1 Sieve Analysis ASTM C-136 1 for 5,000 cft 2 Materials Passing # 200 Sieve ASTM C-117 1 for 5,000 cft 3 Unit Weight ASTM C-29 1 for 10,000 cft 4 Specific Gravity ASTM C-128 1 for 10,000cft 5 Absorption ASTM C-128 1 for 10,000cft 6 Moisture Content ASTM C-566 1 for 10,000 cft 7 Soundness ASTM C-88 1 for 50,000 cft 8 Clay Lumps & Friable Particles ASTM C-142 1 for 20,000 cft 9 Sand Equivalent ASTM C-2419 1 for 20,000 cft 10 Organic Impurities ASTM C-40 5 per source for initial approval. 1 per month after approval per source or 50,000 cft 11 Light Weight Particles ASTM C-123 1 for 50,000 cft 12 Petrography Analysis ASTM C-295 3 no. per source for initial approval. 13 Mortar Bar Test for Potential Alkali Silica Reactivity ASTM C-227 As required by the Engineer. Table 3(e): Testing Frequency for Coarse Aggregates Sr. Test Designation Testing Frequency 1 Sieve Analysis ASTM C-136 1 for 5,000 cft 2 Materials Passing # 200 Sieve ASTM C-117 1 for 5,000 cft 3 Unit Weight ASTM C-29 1 for 10,000 cft 4 Specific Gravity ASTM C-127 1 for 10,000cft 5 Absorption ASTM C-127 1 for 10,000cft 6 Moisture Content ASTM C-566 1 for 5,000 cft 7 Soundness ASTM C-88 1 for 50,000 cft 8 Clay Lumps & Friable Particles ASTM C-142 1 for 50,000 cft 9 Los Angeles Abrasion ASTM C-131 1 for 20,000 cft 10 Light Weight Particles ASTM C-123 1 for 50,000 cft 11 Petrography Analysis ASTM C-295 3 no. per source for initial approval. 12 Mortar Bar Test for Potential Alkali Reactivity ASTM C-227 As required by the Engineer. Table 3(f): Testing Frequency for Concrete Sr. Test Designation Testing Frequency 1 Compressive Strength ASTM C-39 1 for 2,000 cft per class per batch plant 2 Slump ASTM C-143 1 for 2,000 cft per class per batch plant 3 Air Content ASTM C-231 1 for 2,000 cft per class per batch plant 4 Temperature ASTM C-1064 1 for 2,000 cft per class per batch plant 5 Fresh Density ASTM C-138 1 for 2,000 cft per class per batch plant
  • 10. 118 Table 3(g): Testing Frequency for Admixtures Sr. Test Designation Testing Frequency 1 Air entrainment ASTM C-260 As Required 2 Admixtures (water reducing) ASTM C-494 As Required 3 Admixtures plasticizers ASTM C-494 As Required 4 Curing compound ASTM C-309 As Required 2.3 Laboratory and Field Tests Performed and Required A comparison of the number of laboratory and field tests performed and required at the project site is shown in Table 4. Table 4: The Abstract of Quality Control Activities for the Taunsa Barrage Emergency Rehabilitation and Modernization Project (MPR, 2007) Sr. Description of Testing Number of Tests Performed Number of Tests Required A. Laboratory Testing 1 Gradation of Coarse Aggregates 1,124 950 2 Gradation of Fine Aggregates 551 482 3 Unit Weight of Coarse Aggregates 641 477 4 Unit Weight of Fine Aggregates 411 286 5 Specific Gravity of Coarse Aggregates 499 456 6 Specific Gravity of Fine Aggregates 293 242 7 Sand Equivalent 330 289 8 Los Angeles Abrasion 371 253 9 Absorption of Coarse Aggregates 499 456 10 Absorption of Fine Aggregates 293 242 11 Brick Testing 212 As Required 12 Cylinder Testing 24,129 23,586 13 Cylinder Casting 25,698 25,242 14 Soundness of Coarse Aggregates 58 80 15 Soundness of Fine Aggregates 62 59 16 Atterberg Limits 54 As Required B. Field Testing 1 Temperature 6,821 6,745 2 Slump 5,898 5,821 3 Cylinder Moulding 26,034 25,242 4 Field Density Tests 2,189 As Required 3. Concluding Remarks In construction project due to the involvement of various stakeholders in quality control and assurance, issues of quality control arise in virtually all the functional areas of construction activities. Within the organizational structure of the stakeholders in the Taunsa Barrage construction project, a limited number of quality assurance/quality control (QA/QC) personnel were responsible for an increasingly large workload involving many more complex practices than found in traditional construction. To ensure the continued quality of rehabilitation of the barrage facilities, several approaches are being considered, including automation. The computer-aided technology in particular shows great promise in creating tools
  • 11. 119 to assist QA/QC elements. Past development of QA/QC in Pakistan has shown that the stakeholders must become involved early in the process to ensure suitable performance. However, in developing some QA/QC systems, the stakeholder is not known and the system cannot be tailored for a particular level of domain knowledge. When this situation occurs, it is necessary to provide flexibility in the system to handle users with differing levels of knowledge about the domain. Incorporating this flexibility into a computer module is a major problem in current QA/QC development and different approaches have been tried to deal with the problem. The experience of quality control and assurance during the construction of Taunsa barrage can lead to following observations: • The performance specifications for construction operations specifying the required construction process and specifying the required quality of finished facility remained absent in term of application and implementation in the project. • The statistical sampling methods (variable and attributes) commonly used for the quality control has not been used in the project. • Accurate and useful information collection during construction is an important part of maintaining quality performance. • The capability of the contractors after the pre-qualification has been evaluated and PQMS are than developed for a specific project. • In developing countries like Pakistan the quality awareness and consciousness limits is required to be communicated among the stakeholders through seminars, conferences, workshops etc. • As in Pakistan, the PQMS as per ISO for the construction industry is relatively new in implementation and adaptation, thus project oriented PQMS are prerequisite before the commencement of the actual construction particularly on mega projects. 4. References Askari, (2008). Askari cement, http://www.askaricement.com, 01/15/08. Arcelor, (2007). Arcellormittal commercial RPS sheet piling, http://www.arcelormittal.com/sheetpiling, 12/26/07. ASTM, (2007). ASTM international standards worldwide, http://www.astm.org/cgi- bin/SoftCart.exe/index.shtml?E+mystore, 12/26/07. Chung, H.W. (2007). Understanding quality assurance in construction, Microsoft Readers eBooks, eBooks Mall Inc, http://www.ebookmall.com/ebook/74105-ebook.htm , 12/12/07. DECORA, (2007). Water stop product details, http://www.decora.com.pk/index.php?page=waterstops, 12/26/07. Descon News - Events, (2005). Taunsa barrage rehabilitation and modernization contract, http://www.descon.com.pk/News/desconNewsJuly2005.aspx , 12/20/07. DGKC, (2008). DG Khan cement company limited, http://www.dgcement.com ,01/15/08. FOSPAK, (2007). FOSROC constructive solutions, http://www.fosroc.com/LocationDetails, 12/27/07. FSL, (2008). Fazal Steel – FSL Group, http://www.fazalsteel.com/index1.html, 01/15/08. Hendrickson, C. (1999). “Project Management for Construction”, Prentice Hall, ISBN 0-13-731266-0, PA, USA. ISO, (2007). International organization for standardization”, http://www.iso.org , 12/27/07. JCL, (2008). Javedan cement limited”, http://www.jcl.com.pk/ , 1/15/08. KMLG, (2008). Kohinoor Mapple Leaf Group – Mapple Leaf Cement, http://www.kmlg.com/kmlg/cement_products_1.php , 01/15/2008. MPR, (2007). “Taunsa barrage emergency rehabilitation and modernization project monthly progress report April 2007 – Abstract of Quality Control Activities”, Punjab Barrages Consultants.
  • 12. 120 PMI, (2000). “A Guide to Project Management Body of Knowledge – PMBOK”, Project Management Institute, Four Campus Boulevard, Newtown Square, PA, USA. PSQCA, (2007). Pakistan standards & quality control authority”. http://www.psqca.com.pk/ ,12/27/07. PAK, (2008). Pakistan steel mills Corporation private limited, http://www.paksteel.com, 01/15/08. SIKA Industry, (2007). SIKA industry magazine No. 3, http://www.sika.com/industry.htm ,12/27/07.

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