3·11大地震海啸浸泡后的带裂纹RC钢筋强度鉴定

Seismic Evaluation of Seawater Immersed RC Structure with Crack

为解决在东日本大地震造成的海啸中受到海水浸泡的钢筋混凝土(RC)结构的抗震鉴定问题,在调查国外相关研究的基础上,实地考察了东日本大地震中的受损建筑物。结果表明,只要混凝土表面存在裂缝,海水均将浸入到混凝土内部引起钢筋的腐蚀。通过拉伸试验研究了腐蚀后钢筋的性能变化,结果表明,腐蚀后钢筋的屈服点基本没有变化,最大应力下降了10%左右,变形能力也有所降低。在此基础上建议了海水浸泡后钢筋混凝土结构的抗震鉴定及修复流程。

To solve the problem of seismic evaluation of reinforced concrete （RC） structures which soaked in the tsunami caused by the Great East Japan Earthquake, based on survey of related studies done by foreign scholars, the authors investigated damaged structures in the earthquake. The result is that once crack happens on the surface of concrete, seawater will come into the concrete and lead to corrosion of rebar. Deterioration of rebar＇ s performance after the corrosion was studied through tensile test. The result shows that after the corrosion,yielding point of rebar remains unchanged basically, maximum stress reduces by roughly 10% , and ductility also decreases. Based on this study, a manual for seismic evaluation and repair aimed at seawater immersed RC structure was proposed.