Friday, 13 February 2015



Quality assurance in construction activity relates to proper design, use of adequate quality materials and components supplied by various vendors, proper execution of work by the contractor during construction and finally proper care during the use of structure including timely and periodic maintenance and repair by the user of owner. Hence, for quality structure every one starting from the planner, architect, designer, contractor, supplier of materials and the owner become responsible. Only then the final structure will have satisfactory strength, serviceability and long durability ensuring advantageous lower life cycle cost. Most apartment buildings are made of R.C.C. framers. The properties of the completed structures should be consistent with the user requirement and assumptions mad e during the planning and design. This could be achieved only by proper quality assurance measurers. 
Quality assurance involves both technical and organizational aspects. The apartment project should have an explicit quality assurance Plan(plots). This plan should identify key elements necessary to provide fitness of structure and the methods by which it is provided and quantitatively measured. This will give all the stakeholders, the confidence that the realized project will work as per norms in service, thus fulfilling the user needs. This will involve quality checks (audit) of both inputs and outputs. Inputs are in the form of materials machinery and manpower. Workmanship in all stages of batching mixing transportation, placing compaction and curing should be explicitly checked and recorded. The quality of the final product will be satisfactory only if approved plants and machinery and equipments for the process are used. All these should form part of the quality assurance plan. To ensure that the inputs comply with design an inspection procedure should be set up covering materials, records, workmanship and construction. Tests should be made on reinforcements and constituent material of concrete in accordance with Bureau of Indian Standards. There should be clear instructions on inspection standards. The elements should be checked against the design detail with due allowance for dimensional tolerance. The output is in the form of concrete and elements of the structure in place. To ensure proper performance each step in construction should be inspected before the next step is taken. This should be followed as the work progress. Care should be taken to see that elements critical to workmanship, structural performance, durability and appearance are identified for special inspection. The system to verify the quality should include the individual parts of the structure especially the identified critical ones. Immediately after striping the form work, all concrete shall be carefully inspected and any blemishes or defects rectified before proceeding with further work. 

Supervision at each step is a part of the plan. It is not possible to alter concrete dimension once placed. Hence constant and strict supervision is a must during the progress of work. This should include all aspects of concreting such as proportioning, mixing, placing and curing. Supervision is of extreme importance to check the reinforcements and its relative disposition before being covered by concrete. Each and every contributor to the project should make and implement a quality assurance plan with respect to the project. Supplier, contractor and subcontractor’s participation should be covered by the overall plan. The individual agency’s quality assurance plan should fit as a part of overall plan. The plan should define the tasks and responsibilities of all agencies involved. It should state adequate checking procedures and the organizational set-up for documentation. The owner (plots and Flats) should have a periodic maintenance plan to ensure long and trouble-free service from the quality structure. Maintenance is also required to keep the structure in a fit condition to resist unexpected overloading due to disasters such as earthquakes and cyclones. Such maintenance scheme will also reduce the life cycle cost of the structure. 

The documents should necessarily include the following: 

1)Approved site layout plan
2)Architectural plan, 
3)Soil report and bore log data. 
4)Structural design details with structural plan, 
5)Test report and manufacturers certificate for materials concrete mix design details. 
6)Pore cards for site organization and clearance for concrete placement. 
7)Records for site inspection of workmanship. 
8)Periodic filed test results, 
9)Non-conformance reports and correction action taken, 
10)Quality control charts. 
11)Completion report with a suggested maintenance scheme. 
12)Quality control charges are necessary if concrete is in continuous production over a long period of time.

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