钢筋混凝土适筋板式构件的抗扭刚度  

TORSIONAL RIGIDITY OF UNDER-REINFORCED CONCRETE SLABS

作　　者：唐亮[1] 聂建国[2] 

机构地区：[1]中交公路规划设计院有限公司,北京100088 [2]清华大学土木工程系,结构与振动教育部重点实验室,北京100084

出　　处：《工程力学》2009年第6期89-94,115,共7页Engineering Mechanics

基　　金：西部交通建设科技项目(200731849405)

摘　　要：在超静定结构中,受扭构件所承担的扭矩必须根据其抗扭刚度来确定。该文对适筋纯扭板式构件的抗扭刚度进行了研究。适筋纯扭板式构件的工作曲线可理想化为四段直线组成,以(A)混凝土开裂,(B)构件裂缝全面形成、按"空间桁架"模式开始工作,(C)钢筋屈服、构件达到承载力为特征点。混凝土开裂前构件的抗扭刚度按连续均质体受扭导出,采用钢筋混凝土变角软化桁架模型(RA-STM)薄膜元理论推导出构件开裂后的抗扭刚度。通过对部分试件的计算验证,计算曲线与试验曲线吻合良好,表明该方法适用于适筋纯扭板式构件全过程抗扭刚度的计算。To determine the torsional moment for a statically indeterminate structure, the torsional rigidity of each member is required. This paper presents a procedure for calculating the torsional rigidity of under-reinforced concrete slabs. A typical torque-twist curve was idealized as a polygonal line containing 4 segments, broken at points of initial cracking, absolute cracking and reinforcement yielding. At the uncracked state, St. Venant＇s theory was used. The post-cracking torsional rigidity was derived from the rotating-angle softened truss model theory. Comparisons with some published testing results demonstrated that this method can predict ＂load-deformation＂ history of under-reinforced concrete slab.

关 键 词：钢筋混凝土构件 板式构件 抗扭刚度 纯扭 变角软化桁架模型 

分 类 号：TU973.14[建筑科学—结构工程]