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 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 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 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 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 the work progresses. 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 structure especially the identified
critical ones. Immediately after stripping the formwork, 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 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 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 over-loading due to disasters
such as earthquakes and cyclones. Such maintenance scheme will also reduce the
life cycle cost of the structure.
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