基于塑性理论的钢筋混凝土板冲切开裂滑移模型  

Crack slip model for punching capacity of reinforced concrete slab based on the plastic theory

作　　者：易伟建[1] 刘彪[1] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082

出　　处：《西安建筑科技大学学报（自然科学版）》2017年第1期42-47,共6页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51338004;51178175)

摘　　要：在塑性理论的基础上引入新的概念,认为斜截面形成塑性屈服面的同时在该斜截面上开裂发生滑移才会引发节点冲切破坏.通过假设的斜截面上的应力分布,推导求出了圆板径向的斜截面开裂荷载;另一方面,采用抛物线型的Mohr-Coulomb可以得到塑性极限荷载.基于此破坏机理,得到集中力加载和均布荷载加载下板柱节点抗冲切承载力的求解方法,并根据试验结果对相关参数进行修正,经检验计算结果与试验结果吻合良好,同时根据计算结果对公式进行了简化,可应用于工程实践.此模型也合理地解释了板柱节点在集中力作用下冲切锥的角度大于均布荷载作用下板柱节点冲切锥角度的现象.Based on plastic theory, this paper introduced a new concept, th a t the oblique section came into the yield situation and at the same time the slab-column oblique section cracked and slipped, which caused the punching failure in the slab-column joint. The oblique section cracking load could be derived by supposing the stress distribution on the oblique section and the plastic limit load could also be obtained on the basis of the parabola Mohr- Coulomb principle. Based on this failure mechanism, the solving methods aimed at the punching shear capacity of the slab-column joints under concentrated loads and uniformly distributed loads were obtained respectively. In addition, the related parameters were corrected according to experimental results. The calculations were found in good agreement with the experimental data. At last, the formulas applied to engineering practice were simplified according to the calculations. This model presented in this paper could also reasonably explain the phenomenon in which shearing-awl angle under concentrated force was greater than that under the uniform load.

关 键 词：混凝土板 冲切强度 临界斜裂缝 塑性理论 MOHR-COULOMB准则 

分 类 号：TU313.2[建筑科学—结构工程]