装配式钢-薄层UHPC组合梁大直径短栓钉连接件抗剪性能有限元分析

Finite Element Analysis on Shear Performance Large-Diameter Short Stud Connectors in Prefabricated Steel-Thin UHPC Composite Beams

为研究装配式钢-薄层UHPC组合梁中大直径短栓钉的抗剪性能,通过有限元软件ABAQUS建立栓钉推出试验模型,主要研究栓钉直径、孔洞大小、孔洞形状以及单孔内配置栓钉数量对其抗剪性能的影响。研究结果表明:试件破坏模式均为栓钉剪断和混凝土板局部压坏;栓钉直径是影响抗剪承载力的主要因素,孔洞大小和孔洞形状对抗剪承载力影响不大,装配式试件较现浇试件抗剪承载力略有提升;单个孔内配置一个大直径短栓钉基本上可代替同等截面面积的两个小直径短栓钉。此外,将有限元得到的抗剪承载力与已有规范计算值对比发现,GB 50010—2017和EC 4中的计算方法预测偏保守,AASHTO LRFD中的计算方法与有限元得到数值吻合较好,并对比6组相关试验数据,验证了其计算方法的准确性。

In order to study the shear performance of large-diameter short studs in prefabricated steel-thin UHPC composite beams,push-out test models were established by finite element software ABAQUS,and the effects of stud diameter,hole size,hole shape and the number of studs configured in a single hole on shear performance of specimens were mainly investigated.The results showed that the failure mode of specimens was the shear failure of studs and the local crushing of concrete slabs.The stud diameter was the key factor affecting the shear bearing capacity,the hole size and hole shape had little effect on the shear bearing capacity,and the shear bearing capacity of prefabricated specimens was slightly higher than that of cast-in-place specimens.One large-diameter short stud in a single prefabricated hole could basically be replaced by two small diameter short studs with the same cross-sectional area.In addition,comparing the shear bearing capacity obtained by finite element method with the calculated values of the existed codes,it was found that the calculation values in GB 50010—2017 and EC 4 were conservative in prediction,and the calculation results in AASHTO LRFD was in good agreement with the results from finite element method,and the accuracy of its calculation method was verified by comparing six groups of relevant test data.