Quality Control and Quality Assurance for Concrete Durability

Abstract

The durability of concrete structures in severe environments is not only related to design and materials but also to construction. Thus, much of the observed durability problems can be ascribed due to lack of proper quality control and quality assurance during concrete construction resulting in poorly achieved construction quality. Upon completion of new concrete structures, the achieved construction quality typically shows a high scatter and variability, and during operation of the structures, any weaknesses and deficiencies will soon be revealed whatever durability specifications and materials have been applied. To a certain extent, a probability approach to the durability design can accommodate the high scatter and variability. However, a numerical approach alone is insufficient for ensuring the durability; greater control and improvements in durability also require the specification of performance-based durability requirements which can be verified and controlled during concrete construction in order to achieve quality assurance. For new major concrete infrastructure, documentation of achieved construction quality and compliance to the durability specification should be essential parts of any rational approach to controlling and increasing the durability. In the present paper, a case study is presented which provides comparisons of work performed under performance and prescriptive durability specifications.