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 or owner. Hence, for quality structure everyonestarting from the planner, architect, designer, contractor, supplierofmaterials 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 RCC frames.
The properties of the completed structures should be consistent
with the user requirements and assumptions made during planning and design.
This could be achieved only by proper quality assurance measures.
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 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 willbe satisfactory only if approved plants and machinery, and equipments for the processare 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 materials 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 theworkprogresses. Care should be taken to see that elements critical to
workman- ship, structural performance, durability and appearance are identified
for special inspection. The system to verify the quality should include the
individual parts of the structureespecially the identified critical ones. Immediately after stripping
the formwork, all concrete shall be carefully inspected and any blemishes or
defects rectified beforeproceeding 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 isof extreme importanceto check the reinforcements and its relative dispositionbefore being covered byconcrete. Each and every contributor to the project should make
and implement a quality assurance plan with respect to the project. Supplier,
contractor and sub-contractor'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 periodicmaintenance plan to ensure long and trouble-free service from the qualitystructure. Maintenance is also required to keep the structure in a
fit condition to resist unexpected over-loading due to disasters such as
earthquakes and cyclones. Such maintenance scheme will also reduce the life
cycle cost of the structure.
Approved site layout plan.
Architectural plan.
Soil report andbore log data.
Structural design details with Structural Plan.
Test reports 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.
Periodic field test results.
Non-conformance reports and correction actions taken.
Quality control
charts.
Completion Report with a suggested maintenance scheme.
Quality control charts are necessary if concrete is in
continuous production over a long period of time.
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