High Performance and Durability Through Design
R. Narayan Swamy
Appears on pages(s):
alkali silica reactions; columns (supports); fiber reinforced concretes; high-performance concretes; porosity; protective coatings; slag cements; structural design; Design
Although the cement-paste matrix is intrinsically protective to steel, it also permits the ingress of deleterious agents that leads to its own progressive deterioration and consequent destabilisation of steel. Further, the development of a highly impermeable cement matrix, per se, may not ensure a high- performance concrete structure in practice, since the development of strength and pore structure are both time-dependent phenomena and aggressive elements somehow find a means of penetrating concrete and initiate a cumulative process of structural damage. This paper advocates an integrated design philosophy from concept to completion and during service life of a concrete structure. It is shown that by selecting concrete constituents that encourage synergic interactions, it is possible to develop a concrete matrix of high strength and excellent durability. However, concrete also needs to be protected from aggressive agents to enable it to attain its full potential and examples are given to show how such techniques can be adopted to ensure durable service life even in the most unfriendly environment. The application of this integrated design strategy is further illustrated with the design of columns exposed to alkali-silica reactivity and the production of cost-effective, fiber-reinforced thin sheets.