以我国西南高烈度地震区勒不果喇吉隧道为研究背景,采用改进的Newmark隐式积分方法和无限元静一动力统一人工边界,对主隧道与横通道组成的空间交叉结构进行了抗震性能研究.结果表明,横通道开挖后,主隧道与横通道交叉形成的空间结构处出现应力集中现象,在地震过程中,各部位安全系数呈交替变化状态,拱顶部位容易出现拉应力,是抗震的薄弱部位,需要采取加固措施,以确保地震作用下主隧道与横通道交叉结构的安全.研究结论对公路隧道横通道抗震设计、施工,有一定参考价值.
Based on the research of Lebuguolaji tunnel in the region of high seismic intensity of southwest China, seismic performance of the intersection of horizontal adit and main tunnel in expressway is studied by using Newmark implicit integral method and unified artifitical boundary. Results show that stress concentration of the intersection of horizontal adit and main tunnel is obvious, and the safety factors alternately change under earthquake action. The arch of the inersecion tends to be tension stress and is the weak part of the tunnel. The research may be as a reference to seismic design and construction of tunnels.