底框结构地震倒塌模式及其抗倒塌方法研究

Collapse model and collapse-resistance measure for masonry buildings with RC framed bottom floor under earthquake

底框结构应用广泛且震害严重,在地震倒塌房屋中占据很大比例。通过对震害资料的分析,总结了底框结构的震害类型,倒塌模式分为底框层倒塌、过渡层倒塌、整体倒塌,其中底框层倒塌情况偏多。然后数值分析底框结构的抗震性能,发现在强震下易于出现脆性破坏,结构突然倒塌。在此基础上,研究确定底框结构的抗震措施,在满足合理层间刚度比的前提下加设翼墙以提高结构的抗倒塌能力,并通过定量分析明确了加设翼墙对提高抗倒塌能力的有效性。尽管对不同地震波下抗震能力的提升幅度有所差别,合理加设翼墙对结构抗震能力确有很大的提高作用。

Masonry buildings with RC framed bottom floor are widely used and perform badly during the earthquake,which account for a large proportion of buildings collapsed in the earthquake. Through the analysis of damage data,collapse-pattern can be split into three types: RC framed bottom floor collapse,transition floor collapse and overall collapse. RC framed bottom floor collapse holds the majority shares. Then research the anti-seismic property of masonry buildings with RC framed bottom floor by using numerical analysis. The results show that it's prone to brittle failure and suddenly collapse when a strong earthquake occurs. On this basis,the study identifies seismic fortification measures for the masonry buildings with RC framed bottom floor. On the premise of reasonable stiffness ratio between the layers,adding wing walls can improve the structure's anti-collapse ability,and through quantitative analysis identified that additional wing walls perform effectively. Despite the differences in the promotion to enhance anti-collapse ability in different seismic waves,reasonable additional wing walls do have great promotion to enhance structure's anti-collapse ability.