变截面CSW-UHPC组合梁负弯矩区弯曲性能试验研究  

Experimental Study on Flexural Behavior of Variable Cross-section CSW-UHPC Composite Beams in the Negative Moment Zone

作　　者：石雄伟 谢寅涛[2] 杜春锦 苗建宝 李立峰[3] 钟文 SHI Xiong-wei;XIE Yin-tao;DU Chun-jin;MIAO Jian-bao;LI Li-feng;ZHONG Wen(Xi'an Highway Research Institute Co.Ltd.,Xi'an 710064,Shaanxi,China;CCCC First Highway Consultants Co.Ltd.,Xi'an 710075,Shaanxi,China;College of Civil Engineering,Hunan University,Changsha 410082,Hunan,China;Hunan Pingyi Expressway Construction and Development Co.Ltd.,Yueyang 410400,Hunan,China)

机构地区：[1]西安公路研究院有限公司,陕西西安710065 [2]中交第一公路勘察设计研究院有限公司,陕西西安710075 [3]湖南大学土木工程学院,湖南长沙410082 [4]湖南省平益高速公路建设开发有限公司,湖南岳阳410400

出　　处：《中国公路学报》2023年第7期193-203,共11页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51978257);陕西省交通科技项目(17-19K,20-04K)。

摘　　要：为改善常规混凝土波形钢腹板(CSW)组合梁受拉区的受力性能,进一步减小结构重量并推动超高性能混凝土(UHPC)在桥梁工程中的应用,提出一种新型变截面预应力CSW-UHPC组合箱梁结构,为研究其基本受力特征,特别是其抗弯与抗裂性能,设计并完成了一片预应力变截面CSW-UHPC组合悬臂箱梁的负弯矩静力模型试验,测试得到试验梁的荷载-应变响应、裂缝开展模式、挠度及破坏荷载等试验结果。依据试验结果对结构的剪力滞效应和钢腹板承剪比进行了研究;并深入研究了CSW-UHPC组合箱梁的抗裂性能和抗弯承载力计算方法;同时,完成了试验梁的非线性有限元分析。结果表明:这种变截面CSW-UHPC组合箱梁表现出良好的受力、变形和抗裂性能;试验梁的悬臂根部截面产生了负剪力滞效应,剪力滞效应越靠近加载点越明显;悬臂端部到根部截面,试验梁腹板承剪比从80.33%逐渐减小至2.15%;试验梁的极限抗弯承载能力和抗裂弯矩的理论值与试验值较为吻合,建议在计算承载力时,k值取为0.1~0.2。研究成果可为变截面预应力CSW-UHPC组合箱梁结构的设计与应用提供参考。In order to improve the bearing performance of conventional concrete composite beams with corrugated steel webs(CSW)in tension zone,further reduce the structural weight and promote the application of Ultra-High Performance Concrete(UHPC)in bridge engineering,a novel variable cross-section CSW-UHPC composite beam was proposed in this paper.To study the structural behavior,especially for the flexural and cracking resistance,a large-scale experimental program was designed and performed.Experimental results for deflection,strain,crack pattern,and ultimate load were obtained.The shear-lag effect and the proportion of shear force undertaken by steel webs were analyzed according to the test results.Calculation methods for initial cracking moment,nominal cracking moment,and flexural capacity were studied and discussed.Meanwhile,a finite element analysis was conducted using the concrete damaged plastic model in ABAQUS.This research found that the CSW-UHPC composite beams exhibit excellent structural performance with a characteristic of multi-cracking behavior.The shear-lag effect was obvious closer to the loading point and the negative shear-lad effect was observed at the root of cantilever.The proportion of shear undertaken by steel web shown a decreasing trend closer to the root of cantilever,and Cantilever end section web bearing The proportion of shear is 80.33%,root section is only 2.15%.Calculation results for flexural capacity and cracking moment were in good agreement with the test data and were safe for practical engineering.It is recommended that the k value should be 0.1-0.2 when calculating the flexural capacity.The research results of this paper can provide reference for the design and application of variable cross-section prestressed CSW-UHPC corrugated steel web beams.

关 键 词：桥梁工程 变截面CSW-UHPC组合梁 弯曲性能试验 抗裂性能 

分 类 号：U448.35[建筑科学—桥梁与隧道工程]