火灾后双钢板-混凝土组合剪力墙抗震性能有限元分析

为探究火灾后双钢板-混凝土组合剪力墙抗震性能，建立并验证了温度场模型与力学模型。基于相同建模方法，对剪力墙建立了足尺的火灾前后模型，分析不同参数对剪力墙抗震性能影响。结果表明：（1）对于未受火墙体，增大轴压比和剪跨比能够提高墙体的抗弯承载力和变形能力。增大墙体配筋率可以提高抗弯承载力，但对变形能力影响不大。（2）随着火灾时间的加长，墙体在火灾后的初始刚度和抗剪承载力越低。当轴压比越大时，火灾时间的影响越显著。（3）高厚比和轴压比较大的墙体在长时间火灾后，其破坏模式将转变为墙体整体迅速朝着受火侧失稳，抗震性能急剧退化。（4）对于弯曲破坏的墙体，火灾增大了墙体的变形能力，对于压弯破坏的墙体，火灾引起的墙体整体失稳将削弱墙体的变形能力。

Finite Element Analysis of Seismic Performance of Concrete-Filled Double Steel Plate Composite Shear Wall After Fire

In order to explore the seismic performance of Concrete-Filled Double Steel Plate Composite Shear Wall after fire, the temperature field model and mechanical model were established and verified. Based on the same modeling method, a full-scale model of shear wall before and after fire was established to analyze the influences of different parameters on the seismic performance of shear wall. The results show that:(1) Before fire, increasing the axial compression ratio and shear span ratio can improve the flexural bearing capacity and deformation capacity of the wall. Increasing the reinforcement ratio of the wall can improve the flexural bearing capacity, but has little effect on the deformation capacity; (2) With the increase of fire time, the initial stiffness and shear capacity of the wall decrease. The larger axial compression ratio, the greater the impact of fire time; (3) After a long time fire, the failure mode of the wall with a large height-thickness ratio and a large axial compression ratio changes into the failure mode that the whole wall rapidly loses stability towards the fire side and the seismic performance deteriorates sharply; (4) For the wall with bending failure, fire increases the deformation capacity of the wall, whereas the overall instability of the wall caused by fire will weaken the deformation capacity of the wall for the wall with compression-flexure failure.