焊接栓钉型钢混凝土梁纯扭试验及损伤分析

Pure torsional experiment and damage analysis of welded stud steel reinforced concrete beams

为研究焊接栓钉型钢混凝土梁的受扭性能,设计并完成了7根焊接栓钉型钢混凝土梁试件和2根对比梁试件在纯扭作用下的静力荷载试验。试验主要考虑了焊接栓钉间距、直径、长度和位置4个变化参数对试件抗扭性能的影响。通过试验观察了试件扭转破坏形态,揭示了试件的抗扭机理,获取了扭矩-扭率曲线、扭矩-应变曲线及相关特征点参数,分析各变化参数对其抗扭性能的影响,最后基于能量守恒定律,分析了纯扭作用下试件的耗能性能和损伤演变规律。结果表明:焊接栓钉型钢混凝土构件具有较好的抗扭和耗能性能;在型钢腹板焊接栓钉比在翼缘焊接栓钉对提高构件的抗扭性能更有效;在型钢的翼缘和腹板同时焊接栓钉,可以提高试件的耗能性能和抑制试件内部损伤发展。

In order to study the torsional performance of welded stud steel reinforced concrete ( SRC) beams,static load tests of seven welded stud SRC beam specimens and two contrastive beam specimens without stud under pure torsion were carried out . The impacts of displacement,diameters,length and location of welded studs on torsional behavior of specimens were considered in the test. The torsional failure patterns of the members were observed and the torsional resistance mechanism of the members was revealed. The torque-torsion ratio curves,torque-strain curves and related characteristic parameters were obtained,and then the impacts parameters of torsional mechanisms on the welded stud SRC specimens were anlalyzed. Finally,based on the law of conservation of energy,the energy dissipation performance and damage evolution law of specimens under pure torsion were analyzed. The results show that the steel reinforced concrete members with welded studs have good torsional resistance and energy dissipation performance;the welded studs in steel web is more effective than the welded studs in steel flange to improve the torsional resistance of specimens;the welded studs in both steel flange and web can improve the energy dissipation performance and restrain the development of internal damage of the specimens.