【摘要】 运用Newmark隐式时间积分有限元法并采用粘-弹性人工边界,进行了隧道三维地震反应分析。在不同的围岩材料、衬砌类型情况下,分析了隧道洞口段衬砌应力和位移沿隧道轴线方向的变化规律以及采取注浆加固围岩方法的减震效果。计算结果表明:抗震设防长度主要与洞口段围岩性质有关,洞口段松软、破碎的围岩越长,隧道的设防长度就越长;隧道的断面形式以及洞口段临空面的存在与隧道的设防长度关系不大;在地震荷载作用下,洞口段隧道衬砌产生了很大的轴向应力;可采用注浆加固洞口段围岩的方法减小洞口段衬砌的应力和位移。更多还原

【Abstract】 Based on Newmark’s step-by-step implicit integration method,3-D seismic responses of tunnels were performed by using viscous-spring artificial boundary.The orderliness of stresses and displacements in the liner along the axial direction of the tunnel were analyzed under various type tunnel liner and multiform conditions of surrounding rock.The effects of shock absorption measure reinforcing surrounding rock were studied.The results show that the anti-seismic fortified length in tunnel outlet mainly relates with conditions of surrounding rock.The longer of the weak and fragmental surrounding rock,the longer of reinforced liner in tunnel outlet.It is not impressible between strengthened length and the shape of tunnel and empty surface in tunnel outlet.The big axial stresses in liner were brought under the seism.The stresses in the lining of the tunnel were decreased when the method of reinforcing surrounding rock was used.The results provide references for the anti-seismic tunnel design.更多还原