基于扩展有限元的组合梁推出试验精细化分析  

Refined Analysis on Push-out Test of Composite Beams using Extended Finite Element Method

作　　者：韩庆华[1,2] 王一泓[1] 徐杰[1,2] 邢颖[1] 

机构地区：[1]天津大学建筑工程学院,天津300072 [2]天津大学滨海土木工程结构与安全教育部重点实验室,天津300072

出　　处：《建筑钢结构进展》2015年第1期36-41,共6页Progress in Steel Building Structures

基　　金：国家自然科学基金(51178307);天津市自然科学基金(11JCZDJC24000)

摘　　要：大量工程实践表明,组合梁的破坏主要源于抗剪栓钉的疲劳破坏。在疲劳荷载下,承受拉压循环应力的栓钉裂纹萌生、扩展至最终断裂,使钢梁与混凝土的组合作用失效,所以研究栓钉中裂纹萌生及扩展规律对实际工程具有重大意义。扩展有限元(eXtended Finite Element Method,XFEM)是近年来发展起来的一种求解涉及移动非连续问题的有效方法。基于ABAQUS平台利用此方法建立了组合梁推出试验的模型,进行了静力承载力以及疲劳寿命分析,模拟了栓钉中裂纹从萌生到断裂失效的过程,并根据计算结果拟合推出了试验中栓钉的应力幅-寿命曲线,与试验结果及相关规范进行了对比。结论表明扩展有限元的方法具有较强的裂纹模拟能力,计算方便,结果精确,可推广应用于此类断裂问题。The fatigue fracture of studs is a primary factor causing the failure of composite beams based on previous engineering practices. When subjected to fatigue loads, the studs generate repeated cycles of tension and compression stresses which result in the initiation and propagation of cracks. The composite action between steel beam and concrete slab fails when the studs are broken, and thus it is of great importance to study the crack initiation and propagation on the studs. In recent years, XFEM （eXtended Finite Element Method） emerges as an effective method in solving moving and discontinuous problems. In this paper, a numerical model using XFEM in ABAOUS to simulate push-out test of composite beams is developed, and the static bearing capacity and fatigue behavior of composite beams are studied. Also,the process from crack initiation to failure is simulated,and the linear fitting S-N curve of studs is presented and compared with the test results and relevant code specification. The results indicate that XFEM is a powerful tool for crack simulation,due to relatively easy convergence and accurate results. Therefore, XFEM can be easily applied in similar fracture problems.

关 键 词：扩展有限元 组合梁 推出试验 栓钉 裂纹 疲劳寿命 

分 类 号：TU398[建筑科学—结构工程]