单元式双钢板组合剪力墙抗侧性能影响因素分析

Parametric Analyses on Lateral Performance About Modular Composite Shear Wall with Double Steel Plates and Infill Concrete

单元式双钢板混凝土组合剪力墙是一种新型的双钢板混凝土组合剪力墙,主要构造是墙体上下的边缘梁与墙单元利用螺栓进行连接。墙体单元在工厂预制,整片墙体在施工现场全螺栓装配。因此该新型双钢板混凝土组合剪力墙施工方便快捷、便于组合拆装,可以实现建筑物生命周期结束后的全更换,既绿色环保又节省成本。在此基础上,对此新型双钢板混凝土组合剪力墙的抗侧力学性能进行了基本分析。首先结合箱型双钢板组合剪力墙的抗剪性能试验研究,建立了ABAQUS有限元模型进行验证,论证了所建立的ABAQUS模型的可靠性。然后建立了23个单元式双钢板混凝土组合剪力墙的有限元模型,研究了墙体分割单元数量、混凝土抗压强度、钢材屈服强度、轴压比和钢板厚度对其抗侧承载力、抗侧刚度和延性等基本力学性能的影响。1)墙体单元数量的变化范围为1~4,随着墙体单元数量的增多,墙体屈服荷载及峰值荷载均降低,墙体的总承载能力逐渐降低;墙体的极限位移逐渐增大,延性系数越来越大,变形能力有所提高。2)混凝土抗压强度的变化范围为30~80 MPa,随着混凝土强度的提高,墙体的抗侧刚度略有提高,极限位移基本呈现减小的趋势,墙体的延性系数逐步减小,衰减幅度较小。墙体的变形能力逐渐降低,但减幅并不大。3)钢板屈服强度的变化范围为235~500 MPa,随着钢板屈服强度的增大,墙体的屈服荷载和峰值荷载逐渐增加,承载能力有所增加;墙体的屈服位移及极限位移逐渐增加,墙体的延性系数逐渐增加,变形能力有所提高。4)轴压比的变化范围为0.1~0.6,每级增加0.1,在轴压比较小时,提高轴压比能够提高组合剪力墙的屈服荷载及峰值荷载。5)钢板厚度的变化范围为2~6 mm,随着钢板厚度的增大,墙体的屈服荷载和峰值荷载逐渐增加,承载能力有所增加,墙体的初始抗侧刚度和延性系数逐渐增加,变形能力有所提高。通过分析可以得到:增大混凝土强度、钢板屈服强度、钢板厚度能够提高承载力,另外,提升钢板屈服强度和钢板厚度均会提高其延性;单元式双钢板组合剪力墙在水平荷载作用下的抗侧刚度由混凝土部分和钢板两部分共同贡献,增大钢板厚度能够提高其抗侧刚度;墙体单元数量越多,其初始刚度越小,承载力降低。建议在满足施工环境的条件下,两个相邻框架柱之间墙体的单元数量不宜超过3。

A new modular composite shear wall with double steel plates and infill concrete is proposed for increasing lateral resistance of steel frame.The shear wall module is connected to the upper and lower beams by bolting.The wall modules are prefabricated in the factory,and the whole wall is fully bolted on the construction site.Therefore,the new type of composite shear wall is convenient and quick to construct,convenient for assembly and disassembly,and it can be removed at the end of the building life,and it is green and environmentally friendly.In thi paper,the lateral performance of the modular composite shear wall with double steel plates and infill concrete was analyzed numerically.First,the experimental results on concrete filled steel box shear wall were referred to establish the ABAQUS finite element model for predictions,which shows the reliability of the established ABAQUS model.Then the 23 finite element models of the modular composite shear wall with double steel plates and infill concrete were established,and the number of wall modules,concrete compressive strength,steel yield strength,axial compression ratio and steel plate thickness were investigated to discuss the influence on the lateral resistance,the lateral stiffness and the ductility.The wall can be divided into 1 to 4 modules.With the increase in the number of divided wall modules,the yield load and peak load of the wall decrease,and the overall capacity of the wall gradually decreases;the ultimate displacement of the wall gradually increases,the ductility coefficient became larger and the deformation capacity increased.For concrete compressive strength is taken as from 30 MPa to 80 MPa.As the strength of concrete increased,the lateral stiffness of the wall increased slightly,and the ultimate displacement basically showed a decreasing trend.The ductility coefficient of the wall gradually decreased.The deformability of the wall gradually decreased,but the reduction was not large.For the yield strength of steel plates is compared from 235 MPa to 500 MPa.As the yield strength of the steel plate increased,the yield load and peak load of the wall gradually increased,and the resistance increased;the yield displacement and ultimate displacement of the wall gradually increased,the ductility coefficient of the wall gradually increased,and the deformation capacity increased.For the axial compression ratio,the variation range was from 0.1 to 0.6,with an increase of 0.1 for each level.When the axial compression was relatively small,increasing the axial compression ratio can increase the yield load and peak load of the composite shear wall.The steel plate thickness is analyzed from 2 mm to 6 mm.With the increase of the thickness of the steel plate,the yield load and peak load of the wall gradually increased,the resistance increased,the initial lateral stiffness of the wall gradually increased,the ductility coefficient gradually increased,and the deformation capacity increased.From the analysis,it can be found that increasing concrete strength,steel plate yield strength,and steel plate thickness can improve wall resistance,and increasing steel plate yield strength and steel plate thickness will increase its ductility.The lateral stiffness of the modular composite shear wall with double steel plates and infill concrete under horizontal load is contributed by the concrete part and the steel plate.Increasing the thickness of the steel plate can improve its lateral stiffness.The more the number of the wall is divided into modules,the lower the initial stiffness and the lower the overall resistance.It is suggested that the number of divided modules should not exceed 3 under the conditions of meeting the construction environment.