Removal Area of Deteriorated Concretes for Concrete Repairs

초록

This work proposes the concrete removal area for the repairs of deteriorated concretes based on comparison between three types of concrete deterioration (water staining, cracks, delamination) and chloride content testing results. Since concrete deteriorates due to the chloride in deicing salts according to the mechanism of concrete deterioration, chloride content tests were conducted on pier cap, pier, and abutment. The values of the chloride content measured on water stained concrete surface were significantly higher than those on non-water stained concrete surface, which supposedly were led by deicing salts. The values of chloride content surrounding the steel reinforcements of deteriorated concrete elements such as cracks and delaminations were well above the critical value of 1.2 kg/m3. Comparing proposed removal areas in this study, which are ① water stain boundary+50 mm, ②delamination initiation+150 mm, and ③ crack end+150 mm, large sound areas are expected to be removed in the case of water stain boundary+50 mm. On the other hand, the advantages of delamination initiation+150 mm and crack end+150 mm are that they minimize the loss of sound areas when compared with cases of water staining. Consequently, the proposal of removal area is: “The removal area of the deteriorated concrete is the maximum value between delamination initiation+150 mm and crack end+150 mm”. © 2023 by Korea Concrete Institute.

키워드