RC剪力墙宏单元模型中抗剪弹簧的处理方法

On the Shear Resistant Spring of the Macro Element Model for RC Shear Walls

本文依据一种新型 6自由度刚杆一弹簧单元的剪力墙宏单元模型 ,针对两种不同的单元边界条件 (εx=0与σx=0 ) ,及基于修正压区理论的两种不同的二维混凝土本构关系(分别定义于全应变主轴系下与弹性应变主轴系下 ) ,对中高RC剪力墙进行了弹塑性推覆 (push over)分析。对比分析结果表明 ,不同方法所得到的局部剪应力—剪应变曲线虽然存在差别 ,而顶部水平方向的荷载—位移曲线却非常接近 ;采用εx=0及基于全应变主轴系下的修正压区理论 ,因无需迭代而计算量最小。这对于以减少计算量。

The determination of the stiffness of shear resistant spring in a shear wall macro element model is a key problem in the process of modeling A new shear wall macro element model formed with rigid bar?spring elements of six degrees of freedom is used in push?over analysis of medium high RC shear wall,according to two element boundary conditions ( ε x=0 and σ x=0)and two different two?dimensional concrete constitutive relations based on modified compression field theory(defined under the principal total strain axes and the principal elastic axes respectively) Comparison of the analytical results shows that,although the local shear stress?strain curves obtained by different schemes are different,the top horizontal load?displacement curves of the wall are quite close to each other The computational work is minimum by assuming ε x=0 and adopting the modified compression field theory based on the principal total strain,since no iteration is needed It has significant meaning for shear wall modeling,which aims at the whole deformation description with less computational effort