带耗能腋撑型钢混凝土梁转换结构抗震性能参数分析

Parametric analysis of seismic behaviors of SRC beam transfer structures with supplemental energy dissipation haunch brace

带耗能腋撑型钢混凝土梁转换结构是新型的转换结构,通过试验研究验证该新型结构与普通型钢混凝土转换结构相比具有良好的耗能能力和抗震性能。采用有限元数值模拟方法,研究框架柱轴压比、转换梁托柱轴压比、腋撑设置位置、腋梁刚度比等设计参数对该新型结构抗震性能的影响。分析结果表明,在框架柱和托柱轴压比较大的结构中设置耗能腋撑,可以更加明显的改善结构的抗震性能。综合结构响应分析和腋撑变形耗能分析的结果,得出腋撑角度θ的最佳取值为30°～45°,腋撑端部距梁端距离a的最佳取值为Lb/6～Lb/5,腋梁刚度比Kh'的最佳取值为0.2～0.3。

Steel reinforced concrete （SRC） beam transfer structure with supplemental energy dissipation haunch brace （EDHB） is a new kind of transfer structure. Experimental investigations verified that the new type of transfer structure has good energy-dissipating capacity and better seismic performance, compared with normal SRC transfer structures. The influences of axial compression ratio of frame columns and columns supported by the transfer beam, arrangements of EDHB, stiffness ratio of EDHB to transfer beam （ Kh＇ ） by using the finite element method. Results show that , on the seismic behaviors of this type of structure were studied the seismic behaviors of the transfer structure can be more significantly improved by adding EDHB when the axial compression ratios of the frame columns and columns supported by the transfer beam are relatively large. By summarizing the results of the structural responses and the deformation and energy dissipation of the haunch braces, the optimized design parameters of EDHB can be obtained, the haunch brace angle （ θ ） should be between 30 to 45 degree, the distance （ α ） from the haunch tip to the beam end should be kept at Lb/6-Lb/5 , and Kh＇ between 0.2 and 0.3.