框架-剪力墙结构中避免剪力墙墙肢偏心受拉的设计调整

Design adjustment to avoid eccentric tension of shear wall limbs in frame-shear wall structures

工程设计人员在框架-剪力墙结构的设计中,往往发现部分剪力墙的墙肢即使在多遇地震作用的组合下也会处于偏心受拉状态,且这一现象较为普遍。双肢剪力墙中剪力墙的墙肢出现小偏心受拉时,可能会在墙肢底部出现水平通缝,出现大偏心时也会造成剪力墙刚度退化。本文通过对工程案例中的剪力墙连梁刚度折减系数、墙肢长度、剪力墙洞口大小及墙厚等设计因素的调整,探讨了避免受拉现象产生的途径,以期降低剪力墙偏心受拉对结构安全性的不利影响。研究表明:随着剪力墙承担的倾覆力矩增大,剪力墙墙肢的偏拉程度越发严重;在结构设计中,考虑剪力墙相邻墙肢的整体作用更为合理。

In the design of frame-shear wall structures,engineers often found that some of the shear wall limbs in the frame shear wall structures may be in tension state even in the frequently occurred earthquake at structural design,and this phenomenon is quite common.When one wall limb of the coupled shear wall is in small eccentric tension,it may cause the full-length horizontal crack at the bottom of the wall,and stiffness degradation of the shear wall will also occur when the shear wall is in large eccentric tension.This paper through adjustments of the stiffness of the coupling beams,the length of the wall limbs,the size of wall cavity and the wall thickness of the practical project to avoid tension phenomenon of tension situation and reduced the negative influence of the shear wall in tension situation on the structural safety.The results show that with the increase of the overturning moment of the shear wall,the deviation degree of the shear wall is more serious;in structural design,it is more reasonable to consider the integral function of adjacent wall limbs of shear wall.