变截面波形钢腹板连续组合箱梁破坏试验研究

摘要

研究目的:波形钢腹板组合箱梁在受力特点上因具有显著优势,近年来得以迅速发展并在铁路上已经得到应用.本文依托波形钢腹板连续组合箱梁的模型试验,对波形钢腹板连续组合箱梁全过程试验下的弯剪受力性能和破坏机理进行深入研究,从而明确波形钢腹板连续组合箱梁的破坏机制和失效过程.研究结论:(1)波形钢腹板连续组合箱梁正截面弯曲破坏过程可分为弹性加载阶段、中跨跨中截面开裂阶段、中支座截面开裂阶段和中跨跨中截面钢筋屈服阶段四个阶段;(2)波形钢腹板连续组合箱梁剪力主要由波形钢腹板承担,梁体截面开裂和破坏对梁体的抗剪承载力影响较小;(3)试验梁体外预应力增量与中跨跨中截面挠度基本呈线性相关;(4)本研究成果可为波形钢腹板连续组合箱梁的工程运用提供技术参考.%Research purposes:The composite box girder with corrugated steel webs has developed rapidly and been used in railway,which shows significant advantage on mechanical performance.To ascertain the failure process and mechanical properties of composite box girder with corrugated steel webs,the bending-shear performance and failure mechanism were investigated by the model test.Research conclusions:(1) The failure process of the normal section of composite box girder with corrugated steel webs can be divided into four stages:elastic loading stage,the mid-span section cracking stage,the mid-support section cracking stage and the mid-span section reinforcement yield stage.(2) The shear force of the composite girder is mainly supported by steel webs and its shear performance is less affected by section cracking and failure.(3) The external prestressing increment is linearly associated with the mid-span deflection.(4) The research conclusions can provide technical reference for the engineering application of continuous composite box girder with corrugated steel webs.