承重砖墙托换体系承载力预计模型研究  

Predicting the Bearing Capacity of a Load Bearing Brick Wall /Underpin System

作　　者：杜健民[1,2] 袁迎曙[1,2] 王波[1] 陈耀[1] 焦瑞敏[1] 

机构地区：[1]中国矿业大学力学与建筑工程学院,江苏徐州221116 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221008

出　　处：《中国矿业大学学报》2010年第5期642-647,共6页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(50878207;50538070);中国矿业大学科技基金项目(OB080242)

摘　　要：根据工程实际进行了托换试件设计,设计中考虑了砖的强度、穿筋的数量、托换梁的高度等影响因素.试验与分析结果表明,托换体系有两种破坏形式,一是沿砖砌体和托换梁混凝土界面发生冲剪滑移破坏,二是沿砖砌体跨中出现劈开破坏.托换试件的抗冲剪承载力随着托换梁的高度、砖砌体的强度的增大而提高,托换试件抗劈开破坏承载力取决于托换梁的截面尺寸、穿筋的配置量和支座与托换梁间的摩擦系数等因素.最后建立了托换体系平面桁架力学模型,为了防止发生冲剪破坏,以劈开破坏的设计承载力的1.5倍作为冲剪破坏的验算荷载,如不能满足则加大托换梁的高度.The effects of brick strength,cross reinforcement and underpin beam height on wall strength was investigated in practical designs.There are two failure modes in the under-pinning system：punching shear slippage along the interface between the bricks and the concrete underpin beam;and splitting through the mid-span of the brick-work.The shear capacity of the design increases with an increase in beam height and brick strength.Resistance to splitting depends upon the cross-section of the underpinning beam,the amount of cross-reinforcement and the coefficient of friction between the support and the underpinning beam.A plane frame mechanical model of the design is proposed.A design factor of 1.5 times the splitting load bearing capacity will also avoid shear failure.The height of the underpinning beam should be raised when this criterion is not satisfied.

关 键 词：承重横墙 托换体系 劈开破坏 冲剪破坏 

分 类 号：TU472[建筑科学—结构工程]