装配式地连墙横向焊接缝抗弯性能数值模型分析

Flexural Performance Numerical Model Analysis of Transverse Welded Joints in Prefabricated Diaphragm Walls

[目的]预制装配式地下连续墙(以下简称“地连墙”)幅内横缝是整幅地连墙结构的薄弱部位,因此有必要对接缝刚度及其强度特性进行研究。[方法]结合基坑工程中常用的地连墙,介绍了一种新型预制装配式地连墙横向焊接缝形式,采用数值模拟方法研究了所提新型接缝在弯矩作用下的受力变形规律。[结果及结论]在弯矩作用下,接缝受拉侧角钢端部位置混凝土拉应力最大,接缝受压侧角钢端部位置混凝土压应力最大,接缝以受拉侧混凝土受拉开裂为破坏起始标志。构件的挠度曲线在接缝处基本没有发生突变,接缝的变形性能良好,能够有效阻止接缝处渗漏水。接缝受拉侧的角钢、焊缝及钢筋应力较受压侧大,在受拉侧混凝土产生裂缝后,预制构件的角钢、焊缝及钢筋应力均处于较低水平。

[Objective]The transverse joints within the panels of prefabricated diaphragm walls are the weak points in the entire wall structure.Therefore,it is necessary to study the stiffness and strength characteristics of these joints.[Method]In conjunction with prefabricated diaphragm walls commonly used in foundation pit engineering,a new type of transverse welded joints for prefabricated diaphragm walls is introduced.The force and deformation behavior of this new joint under bending moment actions are studied using numerical simulation methods.[Result&Conclusion]Under bending moment actions,the tensile stress in the concrete at the end of the angle steel on joint tensile side is the highest,while the compressive stress in the concrete at this position on joint compressive side is the highest.The failure of the joint begins with cracks of the concrete on tensile side.The deflection curve of the component shows no significant mutation at the joint,indicating good deformation performance of the joint,which effectively prevents water leakage.The stress in the angle steel,weld,and rebar on joint tensile side is greater than that on the compressive side.After cracks appear in the concrete on the tensile side,the stress in the angle steel,weld,and rebar of the prefabricated component remains at a low level.