九江地震台洞体应变观测环境影响分析

Study on the mechanism of the cave observation strain abnormities resulted in the observation condition factors′changing in Jiujiang Seismic Station

对九江地震台2008—2013年洞体温度年变化、气压上升、集中降雨、抽水和承压含水层卸载对洞体应变产生的异常进行统计,获得应变异常量级范围,建立洞体应变观测简单静力学模型。研究认为,九江地震台山洞线应变年变化由观测基线介质的温度效应引起,而气压、降雨、抽水和含水层卸载引起的应变变化则主要由山体附加应力决定。

By making a statistics about the strain abnormities from the cave temperature′s annual changes, atmospheric pressure rising, high rainfall, pumping water and unloading in the pressure-bearing aquifer during 2008 to 2013 at Jiujiang Seismic Station, we get the information of strain abnormity magnitude ranges. We construct a simple static mechanical model of the cave strain observation in the observation place, and consider that the annual changes of the cave line strain dues to the cave material′s temperature effect, and the else strain abnormities result in the extra-stress of the observation hill body.