砖混教室窗间墙不同构造条件下的破坏特点和抗震性能分析

Failure characteristics and seismic performance analysis of longitudinal wall between windows of brick-concrete masonry classroom buildings with different structural measures

为了研究砖混教学楼窗间墙中构造柱的截面尺寸和配筋对纵向窗间墙破坏特点和抗震性能的影响,设计了5片缩尺纵墙试件,并通过低周反复加载试验对配置不同尺寸和配筋构造柱的墙体试件的破坏破坏形态、滞回特性、变形能力、刚度退化等进行了分析.结果表明,中柱的截面大小和配筋不改变墙体的破坏形态,各墙体试件均发生剪切破坏,按照规范要求设置构造柱的墙体试件表现出较好的抗震性能,构造柱与砖砌体具有较好的协同工作性能,适当增大构造柱截面尺寸能够显著改善墙体的延性耗能性能、变形能力,主裂缝宽度明显减小;增大中柱的配筋率使其成为RC柱时,尽管墙体试件抗侧刚度和承载力得到提高,但墙体的耗能能力和变形能力均出现降低,中柱与砖墙体的协同工作性能明显变差.因此,适当增大构造柱尺寸对于进一步提高砖混教学楼窗间墙的抗震和抗倒塌能力是有利的.

Five reduced-scale wall specimens were designed in order to investigate the influence of section size and reinforcement ratio of middle column on the failure characteristic and seismic performance of longitudinal wall between windows of brick-concrete school buildings.The failure characteristics,hysteretic behavior,deformability and stiffness degradation of each wall specimen were analyzed respectively.The results indicate that all specimens with different middle columns are characterized by shear failure.The specimen designed in accordance with the current code for seismic design generally exhibits good seismic performance where the structural column works well with brick masonry.Increasing section size of structural column can improve the energy dissipation,deformability and the crack distribution of specimen significantly.RC column decreases the energy dissipation and deformability of wall specimens in the highly nonlinear stage,although it can increase the stiffness and bearing capacity of wall specimen.Therefore,increasing the size of structural column properly can enhance the seismic performance and anti-collapse capacity of longitudinal walls between windows of brick-concrete masonry structure.