ABSTRACT
The durability problems may be due to inadequate quality control as well as heterogeneity of the materials, which is increasing due to the use of chemical and mineral admixtures in concrete. Structural concrete faces durability problems all over the world, but the major problems are reported in bridges. Gerwick has cited the durability problems faced by some of the tunnels: The tunnels between Honshu and Kyushu respectively leak so badly that it affects not only the concrete tunnel liners but the rails and the running equipment. Carbon dioxide from the atmosphere is adsorbed on the concrete surface, where it interacts with water and forms carbonic acid, a weak acid. Water, an essential in making concrete, can be detrimental and play an adverse role in hardened concrete. Investigations of deteriorated reinforced-concrete structures have indicated that most of the damages occur because of design errors, errors in construction, misconception in specifications and building codes, and bad workmanship.
