洞室间距对双洞山岭隧道地震动力响应影响分析

Analysis of the influence of interval between double tunnels on the seismic dynamic response of double mountain tunnels

近年来地震活动频繁,强震导致部分隧道地下结构损坏,而当前国内对隧道地下结构的抗震研究不足,特别是对不同间距下的双洞隧道的抗震研究更少,因此,亟需对此问题进行深入研究。本文以高烈度区雅泸高速公路为研究背景,运用FLAC3D数值计算方法,结合隧道震害调查统计,对不同间距下的双洞隧道地震响应进行系统研究。结果表明:沿室间距对于双洞隧道的地震响应具有重要影响,当双洞间距较小时,隧道之间的地震动力相互作用不容忽视;随着间距增加,双洞隧道的地震响应逐渐减弱并趋近于单洞隧道的地震响应;双洞隧道地震作用的临界间距为2D;震害调查统计结果与数值分析结果相一致。研究结果可为高烈度区双洞隧道抗减震设计与施工提供指导。

In recent years,seismic activity is becoming more and more frequent.Strong earthquakes cause damage to some underground structures of tunnels.However,at present,the research on the earthquake resistance of the underground structures of tunnels in China is insufficient,especially the research on the earthquake resistance of the double tunnels with the change of the interval between double tunnels,which needs further study.In this paper,based on the research background of Yalu Expressway in high intensity area,by using FLAC3 D numerical calculation method,combined with the investigation and statistics of tunnel seismic damage,the seismic response of double tunnels with different intervals was systematically studied.The results showed that the interval between double tunnels had an important influence on the seismic response of double tunnels.When the interval was smaller,the seismic dynamic interaction between double tunnels coulol not be ignored.With the increase of interval,the seismic response of double tunnels gradually weakened and approached to that of single tunnel.The critical interval of seismic action of double tunnels was 2D.The statistical results of earthquake damage survey were consistent with the numerical analysis results.The research results had certain guiding significance for seismic design and construction of double tunnels in high intensity area.