钢管混凝土柱T形件抗震性能试验及数值模拟

为获悉钢管混凝土柱T形件在地震作用下的破坏机理和力学性能,本文进行6个采用单边螺栓的钢管混凝土柱T形件的受拉循环往复加载试验。试验参数包括柱截面类型、钢材型号、端板形状和端板厚度。详细地分析新型T形件的破坏模式、滞回曲线和骨架曲线等。根据欧洲规范EC3的组件法,提出了钢管混凝土柱T形件的力学理论模型和螺栓刚度模型。利用ABAQUS有限元程序对此类新型T形件进行非线性全过程受力分析,考察了试件的破坏形态,试验结果验证计算模型的准确性。研究表明,热轧钢管混凝土柱T形件具有良好的抗震性能、延性和耗能能力;对于冷弯薄壁钢管混凝土柱T形件采用合理的构造措施和钢管厚度,能有效地提高其抗震性能及延性。

Seismic experiments and numerical simulation of T-stub connections to CFST columns

To study failure mechanism and mechanical properties of T-stub connections to concrete-filled steel tubular(CFST) columns,six specimens of blind bolted T-stub connections under tension cyclic loading were carried out.The test parameters included the column section type,steel type,endplate shape and endplate thickness.Failure modes,hysteretic curves and envelope curves for the novel T-stub connections were analyzed in detail.According to component method from EC3 specification,mechanical models and stiffness model of bolt for the blind bolted T-stub connections were proposed.The nonlinear full-stage analysis of the T-stub connection was completed by using ABAQUS software.Failure modes were also investigated and the finite element modeling was validated by the test results.The results show that blind bolted T-stub connections to hot-rolling CFST columns displayed good seismic behaviour,ductility and energy dissipation capability;seismic behaviour and ductility for T-stub connections to thin-walled CFST columns can be improved by using reasonable constructional measures and tube thickness.