梁式与推出加载对钢-混凝土结构栓钉承载力影响机理分析  

Mechanism analysis of influence of beam and push out loading on stud bearing capacity of steel-concrete structure

作　　者：刘冰洁 范亮[1] 石璐 杨玉星 LIU Bingjie;FAN Liang;SHI Lu;YANG Yuxing(School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Wuhan University of Engineering Science,Wuhan 430200,China)

机构地区：[1]重庆交通大学土木工程学院,重庆400074 [2]武汉工程科技学院,湖北武汉430200

出　　处：《混凝土》2024年第1期64-68,共5页Concrete

基　　金：国家自然科学基金(U20A20312)。

摘　　要：针对钢-混凝土结构中栓钉在推出和梁式加载时不同的受力行为,通过开展数值分析及试验验证,研究了两种加载情况下的栓钉承载力、刚度及传力路径等典型受力性能差异,提出了预留孔尺寸效应、钉簇间受力非线性梯度效应及单簇钉群受力簇群效应等影响效应及机理,建立了梁式加载单钉抗剪承载力计算式。研究表明:梁式加载时栓钉抗剪承载力低于推出加载,抗剪刚度高于推出加载;梁式加载极限承载力时栓钉根部受力相较推出加载呈现更为显著的非线性关系;尺寸效应使组合梁中栓钉承载力略高于推出试件;组合梁中簇群效应更为显著,使单钉承载力降低。梯度效应使组合梁栓钉根部受力非线性更为明显。基于上述分析,提出了考虑3种效应的梁式加载单钉抗剪承载力计算式。Aiming at the different stress behaviors of stud in steel-concrete structure under push-out and beam loading,through numeri-cal analysis and experimental verification,the typical stress performance differences of stud in bearing capacity,stiffness and force trans-mission path under the two loading conditions are studied,and the influence effects and mechanisms such as reserved hole size effect,non-linear gradient effect between stud clusters and single cluster effect are put forward.The calculation formula of shear bearing capacity of single nail under beam loading is established.The results show that the shear bearing capacity of stud under beam loading is lower than that under push out loading,and the shear stiffness is higher than that under push out loading.When the ultimate bearing capacity is loaded by beam,the stress at the root of the stud presents a more significant nonlinear relationship than that under push out loading.The size effect makes the bearing capacity of the bolt in the composite beam slightly higher than that of the push out specimen.The cluster effect is more significant in composite beams,which reduces the bearing capacity of single nail.The gradient effect makes the stress nonlinearity of the bolt root of the composite beam more obvious.Based on the above analysis,the calculation formula of shear capacity of single nail under beam loading considering three effects is proposed.

关 键 词：钢-混组合结构 推出加载 梁式加载 抗剪承载力 

分 类 号：TU528.01[建筑科学—建筑技术科学]