논문 상세보기
pp.9-16
As the durability, reparability and maintainability of reinforced concrete structures are emphasized, the early perfomance degradation of concrete structures becomes a serious problem. Moreover, defects in construction materials and constructions inconsistent with the design promote the degradation of perfomance. Some worst buildings have fallen into an irreparable state within a few years. In particular, carbonation in concrete structures has been handled as the most fundamental and critical factor related to the durability of reinforced concrete. As a result, there have been efforts to develop repair materials to control carbonation. As one of these efforts, alkali recovery agents have been presented as materials for increasing the re-alkalization and durability of carbonated concrete structures. However, in applying them in the field, the performance and quality of concrete recovered after an alkali recovery agent is applied has not been fully assessed. Therefore, to examine the recovered perfomance of concrete structures resulting from the application of an alkali recovery agent, the present study assessed the depth of carbonation and the degree of deterioration of 20 years or older reinforced concrete structures, and analyzed the quality of concrete after applying an alkali recovery agent to the structures. This study aimed at providing basic infomation for the application of alkali recovery agents in the fleld. In this experiment, alkali recovery agents of the lithium silicate line, which are most common in Korea, were applied and cured using concrete of the same size. The degree of recovery was investigated according to the length of time in the initial curing stage, and based on the investigation, the maintenance perfomance of the alkali recovery agent was assessed according to the age of exposure to the open air. For these tasks, this experiment sampled concrete of different degrees of deterioration, applied alkali recovery agents to them, and observed re-alkalization and changes in the internal texture of the concrete.
