HPFRCC梁柱组合件节点核心区力学性能及计算模型研究

Research on the Mechanical Properties and Calculation Model of the Joint of Beam⁃Column Subassembly

为了研究高性能纤维水泥基复合材料(High-Performance Fiber Reinforced Cementitious Composites,HPFRCC)对框架结构节点核心区力学性能的影响,本文对6个预期损伤部位采用HPFRCC材料的带板梁柱组合件和1个钢筋混凝土(Reinforced Concrete,RC)梁柱组合件进行拟静力试验,分析其节点核心区受剪承载能力、变形能力等.研究结果表明,与RC梁柱组合件节点相比,HPFRCC梁柱组合件节点核心区的受剪承载力提高了11.1%;峰值点的剪切变形减小了10.3%,节点核心区剪切变形对层间变形的贡献比率降低了22.7%.柱端弯矩增大系数的取值和翼缘板的宽度取值对HPFRCC节点核心区的剪切变形有显著影响,柱端弯矩增大系数达到1.6或者翼缘板宽度取值为8倍板厚都可以使节点核心区峰值点对应的剪切变形控制在0.01左右.采用BPE(Bayesian Parameter Estimation)方法进行理论分析,分别建立HPFRCC梁柱节点的剪切强度计算模型和剪切变形计算模型,模型分析结果与试验结果符合较好.

In order to study the effect of high-performance fiber reinforced cementitious composites(HPFRCC)on the mechanical properties of the joint of the frame structure,quasi-static tests were conducted on six beam-column subassemblies using HPFRCC for expected damage locations and one reinforced concrete(RC)beam-column subassembly.The shear bearing capacity and deformation capacity of joints were analyzed.Compared with the RC specimen,the shear capacity of the joint of the HPFRCC specimen is increased by 11.1%,and the shear deformation of the peak point is reduced by 10.3%.The contribution rate of the shear deformation to the drift is reduced by 22.7%.The column end bending moment amplification coefficientηand the flange width of the slab have significant impacts on the shear deformation of the HPFRCC joint.The shear deformation corresponding to the peak load of the joint can be controlled at about 0.01,when the coefficientηis 1.6 or the flange width is 8 times of plate thickness.The shear strength and shear deformation calculation model of the HPFRCC joint is established through the Bayesian parameter estimation,and the model analysis results are in good agreement with the test results.