抗震墙纵筋最小配筋率评估和分析  

Evaluation and analysis on minimum vertical reinforcement of seismic structural walls

作　　者：鲁懿虬 Lu Yiqiu(Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学,上海200092

出　　处：《土木工程学报》2025年第4期11-23,共13页China Civil Engineering Journal

基　　金：国家自然科学基金(52378530)。

摘　　要：近期地震表明,按最小配筋率设计的抗震墙可发生墙底大裂缝和钢筋过早拉断的现象,极大影响抗震墙安全性能。目前抗震墙最小配筋率研究较少,因无统一理论指导设计,各国规范对最小配筋率的规定各不相同,抗震墙性能差别较大。文章从裂缝形态出发阐明抗震墙最小配筋率的作用机理,并从国内外规范对比、试验数据、理论分析和有限元模拟4个方面对中国规范抗震墙最小配筋率做全面的评估和分析。研究表明我国规范抗震等级为一级、二级时,抗震墙在地震作用下裂缝呈细密形态,具有较好的延性和位移角能力,极限位移角可达2.0%以上;抗震等级为三级、四级的抗震墙一般变形集中于若干大条裂缝,极限位移角在0.5%~1.5%,并在极端情况下可能发生脆性破坏。研究指出我国规范抗震墙最小配筋率在轴压比、墙身配筋率、材料强度等方面的不合理之处,提出了相应的修改建议。文章研究结论可为抗震规范修订提供参考。Recent earthquakes demonstrated that for the reinforced concrete walls in multistory buildings designed with minimum vertical reinforcement(MVR),large cracks at the wall base and premature fracture of vertical reinforcement may occur.Due to the lack of a unified theory for the guidance of design,the specifications on MVR of walls in standards of different countries may differ with each other so that the seismic performance of walls may differ a lot.To better understand the seismic behavior of walls designed by referring to MVR in Code for Seismic Design of Buildings(GB 50011—2010)in China,the effect of MVR is illustrated and the detailed requirements for different seismic grades are evaluated in terms of code comparison,experimental data,theoretical analysis and finite element simulation.Research results show that for walls designed with MVR in terms of Seismic Intensity 1 and 2,fine and dense cracks may occur in walls and the walls still possess good ductility and drift capacity which is larger than 2.0%;for walls designed with MVR in terms of Seismic Intensity 3 and 4,several large cracks may occur in walls,the drift capacity is reduced to only about 0.5%~1.5%,and brittle failures may occur in some extreme cases.Some issues on the MVR requirements in GB 50011—2010 specified according to axial compression ratio,reinforcement ratio in walls and material strength are particularly discussed,and some revisions are suggested.Some research conclusions can be referred to when revising the seismic standards.

关 键 词：抗震墙 混凝土 最小配筋率 规范 延性 裂缝形态 

分 类 号：TU375[建筑科学—结构工程]