CONSTRUCTION MATERIALS

Chapter 2

Quality Control

Quality Control is a common terminology in most construction

sites and is frequently used by the laboratory personnel; however,

its meaning might not be clearly known by everyone. The term

contains two words, quality (which means standards) and control

(which means regulate or monitor). Therefore, Quality Control may

be defined as the organized operations (inspections, sampling and

testing) necessary for regulating or monitoring the work standards.

The main objectives of quality control in a road project are;

o To screen-out and prevent the use of substandard materials in

the project by conducting preliminary and routine testing.

o To inspect the production process and enable quick

corrections whenever production deviates from the project

standards.

o To weigh up and grade the final product for acceptance.

Quality control takes account of materials properties (beneficial

and detrimental behaviour), application methods (workmanship)

and the value of final product. However, since materials testing

and inspections are normally carried out by laboratory personnel

with different levels of knowledge and experience, it is extremely

important to have a standard system that controls and unifies the

laboratory operations in order to ensure reliability of the test

results.

Principally, the main concern in quality control process is not just

the test result recorded during testing, but truth of the result and

its effect on the final product. Therefore, quality control plan

should not be limited to sampling procedure and testing methods

only, but should also take personal knowledge into account, as well

as the attitude and tactics of conducting field inspections and using

the laboratory equipment to avoid erroneous results.

On the other hand, the quality control manager (or engineer)

should prepare a regular calibration schedule for the laboratory

equipment (to retain their precision); and ensure the personnel put

into practice the laboratory principles to avoid injuries and

damages to equipment.