Quality assurance in construction activity relates to properdesign, 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 thecompleted 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.
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 andoutputs. 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.
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 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:
Architectural plan,
Soil report and bore log data.
Test report and manufacturers certificate for materials concrete
mix design details.
Pore cards for site organization and clearance for concrete
placement.
Records for site inspection of workmanship.
Non-conformance reports and correction action taken,
Quality control charts.
Completion report with a suggested maintenance scheme.
Quality control charges are necessary if concrete is in continuous
production over a long period of time.
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