木-钢组合箱梁抗弯性能试验及有限元对比分析  

Test and finite element(FE)analysis on the flexural performance of timber-steel composite box girders

作　　者：刘佳桐 雷云 郦维 陈领 刘瑞越 王解军[1] LIU Jiatong;LEI Yun;LI Wei;CHEN Ling;LIU Ruiyue;WANG Jiejun(School of Civil Engineering,Central South University of Forestry&Technology,Changsha 410004,Hunan,China;Guang’an City,Guang’an District Transportation Bureau,Guang’an,638000,Sichuan,China;Hunan University Design and Research Institute Co.Ltd.,Changsha 410082,Hunan,China)

机构地区：[1]中南林业科技大学土木工程学院,湖南长沙410004 [2]广安市广安区交通运输局,四川广安638000 [3]湖南大学设计研究院有限公司,湖南长沙410082

出　　处：《中南林业科技大学学报》2023年第6期178-189,共12页Journal of Central South University of Forestry & Technology

基　　金：湖南省科技创新团队项目“生态建筑环境材料研发与应用”(2020RC4049);中南林业科技大学科研项目(9010263203077)。

摘　　要：【目的】为促进木结构在大型工程中的应用范围,本研究提出了一种以落叶松胶合木板作为上下翼板、焊接冷弯薄壁槽钢作为腹板并通过螺栓连接的木-钢组合箱梁。【方法】采用分级加载的方式分别对3根木-钢组合箱梁和1根木箱梁进行弯曲加载试验,观测组合箱梁和木箱梁在荷载作用下翼缘和腹板的应变变化、挠度的发展、破坏过程及形态变化,研究其抗弯极限承载力和抗弯刚度等力学性能,并基于ABAQUS建立了有限元模型对组合箱梁及胶合木箱梁进行数值模拟分析。【结果】组合箱梁的翼板与腹板组合性能较好,最终均为下翼缘木板受拉断裂的破坏模式,同时伴随着钢材局部屈曲和上翼缘木材的局部劈裂等破坏;木箱梁为腹板顺纹剪切破坏。相比胶合木箱梁,组合箱梁的抗弯极限承载能力平均提升了30.33%,但初始刚度平均降低了34.42%;根据翼板横向应变分布计算了木箱梁和木-钢组合箱梁上翼缘的剪力滞系数以及有效分布宽度。有限元模型与试验结果吻合良好,能有效预测木-钢组合箱梁及胶合木箱梁的弯曲性能。【结论】木-钢组合箱梁充分发挥了木材和钢材的力学性能,相比于纯木箱梁,抗弯承载力提升显著,说明木-钢组合箱梁是一种科学合理的组合形式,研究成果可为木-钢组合箱梁的后续研究提供一定的理论基础。【Objective】To promote the application of timber structures in large-scale projects,this study proposed a timber-steel composite box girder with larch glued laminated timber plates as the upper and lower flanges and welded cold-formed thin-walled channel steel as the web.【Method】Bending loading tests were carried out on three timber-steel composite box girders and one timber box girder by means of graded loading,and the strain changes,deflection development,failure process and morphology of the flange and web of the composite box girder and timber box girder were observed under the load,and their mechanical properties such as flexural ultimate load capacity and flexural stiffness were studied.The numerical simulation analysis of the composite box girder and glued laminated timber box girder was carried out based on ABAQUS.【Result】The test results showed that the combined performance of the flange and web of the composite box girder was better,and its final failure mode was the tensile fracture of the lower flange timber plate,accompanied by the local buckling of steel and the local splitting of the upper flange timber and other failures.The timber box girder was the shear failure of the web with the grain.Compared with the glued timber box girder,the flexural ultimate load capacity of the composite box girder was improved by 30.33%on average,but the initial stiffness was reduced by 34.42%on average.The shear lag coefficient and the effective distribution width of the upper flange of the timber box girder and timber-steel composite box girder were calculated based on the transverse strain distribution of the airfoil.The finite element model was in agreement with the experimental results and can effectively predict the bending performance of the timber-steel composite box girder and glued laminated timber box girder.【Conclusion】The results showed that the timber-steel composite box girder gives full play to the mechanical properties of timber and steel,and the bending resistance is significantly impr

关 键 词：木-钢组合箱梁 胶合木箱梁 螺栓连接 承载力失效试验 有限元分析 

分 类 号：S781.21[农业科学—木材科学与技术]