螺栓球与钢管组配试件的超低周损伤性能试验研究  

Experimental research on ultra-low cycle damage performance of bolted ball and steel tube assembly specimen

作　　者：杜雷鸣 李海旺[2] 宋夏芸 张洁[2] DU Lei-ming;LI Hai-wang;SONG Xia-yun;ZHANG Jie(Shanxi Engineering Vocational College,Taiyuan 030009,China;Civil Engineering Institute,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]山西工程职业学院,太原030009 [2]太原理工大学土木工程学院,山西太原030024

出　　处：《空间结构》2021年第2期56-64,共9页Spatial Structures

基　　金：国家自然科学基金项目(51578358)。

摘　　要：空间网格结构的杆件及节点遭受灾难地震时易因材料损伤累积而发生超低周疲劳破坏.通过6组12个螺栓球节点的圆钢管试件在轴向循环荷载作用下的拟静力试验,研究了计及节点影响的钢管单元在两种加载制度下的破坏形态、滞回曲线、耗能能力、截面类椭圆化的形成与发展等.试验表明:试件裂纹萌生于杆件中部凹陷区域,少次循环后因损伤累积发生超低周疲劳破坏;类椭圆化最严重的截面位于杆件中部,因类椭圆化发展有限,其耗能能力受限;随着节点抗弯刚度的增大,截面类椭圆化程度、累积损伤均增大,但导致开口断裂提前、总耗能减少.以试验数据为基础,建立了截面类椭圆化与损伤模型的相关公式,为震后螺栓球网格结构杆件承载力评估提供参考.Ultra-low cycle fatigue failure is prone to occur when the rods and nodes of spatial grid structures are subjected to catastrophic earthquakes due to the accumulation of material damage.In this paper,the failure modes,hysteretic curves,energy dissipation capacities,and the formation and development of section ovalization of steel tube under two loading systems are studied through quasi-static tests of 6 groups 12 specimens of steel tubes with bolted ball joints under axial cyclic loading.Test results show that the crack of the specimen is generated in the central depression area of the bar,and the ultra-low cycle fatigue failure occurs due to damage accumulation after a few cycles.The section with the most serious ovalization is located in the middle of the bar,and its energy dissipation capacity is limited due to the limited development of ovalization.With the increase of flexural stiffness of the joint,the degree of ovalization and cumulative damage of the section all increase,but it leads to the early fracture of the opening and the decrease of total energy consumption.Based on the test data,the related formulas of section ovalization and damage model are established,which can provide reference for the bearing capacity evaluation of bolted ball grid structure after earthquake.

关 键 词：螺栓球节点 网格结构 灾难地震 超低周疲劳性能 截面类椭圆化 损伤评定 

分 类 号：TU356[建筑科学—结构工程]