钢纤维高强混凝土二桩厚承台受力机理试验研究  

Experimental study on stress mechanism of steel fiber reinforced high strength concrete two⁃pile thick caps

作　　者：雷杰 王武刚 陈子夏 LEI Jie;WANG Wugang;CHEN Zixia(School of Water Conservancy,North China University of Water Resources and Electric Power,Zhengzhou 450046,China)

机构地区：[1]华北水利水电大学水利学院,郑州450046

出　　处：《建筑结构》2025年第4期81-86,共6页Building Structure

基　　金：河南省高等学校重点科研项目(22A570001)。

摘　　要：为研究钢纤维高强混凝土二桩厚承台的受力性能和破坏机理,进行了12个平面尺寸为600mm×300mm、厚度为200~400mm的钢纤维高强混凝土二桩厚承台试验,得到了不同试验参数二桩厚承台的裂缝开展、破坏形态、荷载-挠度曲线、混凝土和钢筋应变特征,分析了承台有效厚度、钢纤维体积率、配筋率和混凝土强度对承台承载力和破坏形态的影响。在此基础上,采用ABAQUS程序分析了承台破坏形态及应力分布,并与试验结果进行了对比。结果表明,钢纤维高强混凝土二桩厚承台的破坏是桩柱连线范围内钢纤维混凝土沿斜截面劈裂的上下错动引起的剪切破坏;增加承台厚度和在混凝土中掺入钢纤维可显著提高承台承载力,钢纤维体积率采用1.0%较为经济合理;承台的底部钢筋配筋率不宜小于1.2%;钢纤维高强混凝土二桩厚承台传力机理符合拉压杆模型。In order to study the mechanical performance and failure mechanism of steel fiber reinforced high strength concrete(SFRHSC)two⁃pile thick caps,12 SFRHSC two⁃pile thick caps with the plane size of 600mm×300mm and the thickness of 200~400mm were tested.The crack development,failure mode,load⁃deflection curve,concrete and reinforcement strain characteristics of two⁃pile thick caps with different test parameters were obtained.The effects of the cap effective thickness of caps,steel fiber volume fraction,reinforcement ratio and concrete strength on bearing capacity and failure mode of caps were analyzed.On this basis,the failure mode and the stress distribution of caps were analyzed by ABAQUS program,and compared with results of the tests.The results show that the failure of SFRHSC two⁃pile thick caps are mostly due to the shear failure caused by the up and down displacement of the steel fiber concrete within the pile⁃column connection range along the diagonal section.Increasing the thickness of the caps and adding steel fiber into the concrete can significantly improve the bearing capacity of the caps,and the steel fiber volume fraction of 1.0%is more economical and reasonable.The reinforcement ratio at the bottom of the caps shall not be less than 1.2%.The transfer mechanism of SFRHSC two⁃pile thick caps conforms to the strut⁃and⁃tie model.

关 键 词：二桩承台 钢纤维 高强混凝土 试验研究 受力机理 

分 类 号：TU753.2[建筑科学—建筑技术科学] TV431.3[水利工程—水工结构工程]