RC剪力墙无支撑局部加强置换法仿真分析

Simulation analysis of unsupported local strengthening replacement method for RC shear wall

针对混凝土强度不足的RC剪力墙无支撑局部加强置换法,基于正交分析方法设计不同竖向应力水平下置换混凝土的工况,并运用ABAQUS的生死单元模块模拟不同竖向应力水平下置换混凝土的加固方案,分析剪力墙构件在无支撑加强置换后的竖向承载力及抗震性能。即考虑置换剪力墙存在应力滞后现象,通过控制不同竖向应力水平及原剪力墙混凝土初始强度,采用9组不同因素且考虑应力滞后的一次性置换剪力墙模型试件进行低周往复模拟试验,对比原设计情况下的浇筑剪力墙的相关力学参数得出:在较低初始竖向应力水平的工况中,一次性无支撑置换加固后剪力墙构件的承载力能够满足设计要求。为保证在较高初始竖向应力下该方法的可行性,通过使用分批无支撑加强置换施工方法,即对高初始竖向应力水平下的剪力墙构件分两个批次进行置换。分析表明,分批次无支撑加强置换法可适用于高初始竖向应力水平情况。

For the unsupported local reinforcement replacement method of RC shear wall with insufficient concrete strength, In this paper, the working conditions of displacement concrete under different vertical stress levels are designed based on the orthogonal analysis method, and the ABAQUS model change unit module is used to simulate the reinforcement scheme of the replacement concrete under different vertical stress levels, and the shear wall components after the unsupported reinforcement replacement are simulated and analysis the vertical bearing capacity and seismic performance.That is, considering the existence of stress hysteresis in the replacement shear wall, by controlling different initial vertical stress levels and the degree of defects in the original shear wall, 9 groups of replacement shear wall model specimens with different factors and considering the stress hysteresis were used to conduct low-cycle reciprocating simulation tests.Compared with the relevant seismic parameters of the one-time poured shear wall under the original design, it is obtained.With the increase of the initial vertical stress level, the bearing capacity of the structure can meet the design requirements, but the ductility of the components decreases.In order to ensure the feasibility of this method under higher initial vertical stress, in batch unsupported reinforcement replacement construction method is used, that is, the shear wall components under high initial vertical stress level are replaced in two batches.The analysis shows that the in batch unsupported reinforcement replacement method is suitable for high initial vertical stress levels.