钢管混凝土桁梁非线性有限元分析.doc

钢管混凝土桁梁管内混凝土受压应变状态基金项目:国家自然科学基金资助项目(51008079),福建农林大学重点学科建设基金(pytd12006)
第一作者简介:谢志涛(1989-),男,助理工程师,硕士。研究方向:组合结构研究。
*通讯作者:黄文金(1975-),男,博士,副教授,硕士生导师。
谢志涛,孙涵,黄文金*
(福建农林大学交通与土木工程学院,福建福州 350002)
摘要:利用自制的内埋式混凝土应变计和通用有限元软件,对钢管混凝土桁梁试件受压弦杆管内填充混凝土的应变状态进行研究。试验研究结果表明,在单调加载条件下,自埋式混凝土应变计能准确测读受压弦杆管内混凝土的应变状态;混凝土应变随荷载增大呈双折线增长模式,桁梁试件破坏时混凝土受压应变达到5000με。当采用平面塑性梁单元对钢管混凝土桁梁进行整体分析时,不管弦杆受压还是受拉,管内混凝土均应考虑套箍效应;桁梁受压弦杆管内混凝土纵向应变有限元计算值与实测值吻合良好,桁梁试件破坏时混凝土应变处于高套箍状态。
关键词:桁梁;填充混凝土;试验;有限元;应变状态
中图分类号: 文献标志码:A
On strain state of concrete filled pressive chord of concrete filled steel tubular truss girder
XIE Zhi-tao, SUN Han, HUANG Wen-jin
(College of Transportation and Civil Engineering, Fujian Agriculture and Forestry University, Fuzhou 350002, China)
Abstract:The strain state of concrete filled pressive chord tube of concrete filled steel tubular (CFST) truss girder was investigated with self-prefabricated embedded strain gauges and test-verified finite element (FE) model,. Experimental investigation reveals that the embedded strain gauges predicts accurately the strain change of infilled concrete under monotonic loading, and that a bilinear increment curve with a maximum value of 5000με is measured for the concrete pression. When plane plastic beam element model isused for FE analysis of CFST truss girder, the confinement effect should be taken into account for concrete filled in bo