普通民房在爆破地震波作用下的振动破坏分析

摘要

爆破地震波作用于房屋结构体所产生的连续拉扭及超载作用将造成房屋墙面抹灰脱落、结构体裂缝开裂延伸等现象。在各振动物理量中，振动速度中的径向振动分量持续时间长、主频低且接近于房屋结构体自振频率，且楼体高层处径向振动速度分量相对于低楼层的有明显放大，放大系数β＝1.5，经分析认为爆破地震波中的径向速度分量在结构物破坏中是一个主要的因素。通过长期的爆破震动时结构物振动响应数据采集分析及结构体裂缝现象观测，提出了适宜某场区实际特征的普通民房结构体的容许振动速度标准υ=2cm/s。%With to half a year's blast monitoring, it is found that theradial part of the blasting seismic velocity, which lasts a longer duration and whose main frequency is close to low-rise house basic frequency, makes an important part in damae to the low-rise house, such as cosmetic superstructure cracks, failure of the plaster and other second response effects. By analyzing differential floor's response, a function which can stand for their relationship is revealed, and the radial response velocity is magnified in second floor compared with that of the ground floor and the parameterβ=1.5. The paper recommends that the low-rise hosue home's permitted oscillatory velocity is v=2 cm/s when the blasting seismic wave's main frequency domain is 6～15 Hz.