公路隧道位移反演及其稳定性分析

【作者】 王向刚；

【导师】 李术才；

【作者基本信息】 山东大学 ， 岩土与结构工程， 2005， 硕士

【摘要】 本文以实际公路隧道工程为背景,以现场量测资料为依据,建立了一套方便实用的隧道位移反分析方法和围岩稳定性分析方法,并将之应用与实际工程中,产生了一定的技术和经济效益。 本文的主要内容如下: (1) 以神经网络和直接位移反分析方法的基本理论为基础,用Matla b语言编制了基于神经网络的位移反分析程序,并用某挡土墙工程进行了验证。 (2) 以沪蓉西高速公路庙垭隧道监测数据为基础,对围岩参数和初始地应力侧压系数进行了反演,并以此为基础对围岩稳定性进行了分析。对洞周围岩位移随隧道埋深的变化规律进行了计算分析,得出了洞周关键点随埋深变化的计算公式。分析了隧道开挖的空间效应,得出了庙垭隧道的空间效应系数。 (3) 对沪蓉西高速公路龙潭隧道浅埋偏压洞口施工过程进行了数值模拟,分析了锚喷支护、偏压作用、水的作用等诸多因素对围岩稳定性的影响。锚杆和喷射混凝土层对洞周围岩的变形和塑性区的产生起了很大的限制作用。由于地形关系产生的偏压作用对隧道开挖后的二次应力场产生了很大影响,由此产生了围岩的位移场和塑性区与一般隧道有很大不同。由于隧道埋深较浅,直接影响了地表岩层的应力状态,使地表的山坡稳定性受到一定影响。地下水对浅埋隧道围岩的稳定性产生非常不利的影响。更多还原

【Abstract】 According to the on-site measured data, the paper founds a set of convenient and practical methods about the back analysis of tunnel displacement and the stability analysis of surrounding rock. When they are applied to the practical engineering, a certain economic performance is obtained. The primary coverage is as follows:Basing on the basal theory about the Neural network and the direct back analysis of displacement, the program on back analysis of displacement is composed with the computer language "Matlab" and testified by some earth-retaining wall.On account of the monitoring data of Miaoya Tunnel, the paper interchanges the parameters of surrounding rock and the coefficient of lateral pressure of in-situ stresses. Further more the paper does research on the stability of the surrounding rock in accord with it. Through the numerical simulation the paper studies the variation law on the displacement of surrounding rock versus the depth of burial and the computation formula is founded. Through analyzing three-dimensional effect of tunnel excavation, the coefficient of three-dimensional effect in Miaoya Tunnel is obtained.Simulating the tunnel with shallow-depth and eccentrical compression with numerical simulation techniques, it is known how the bolt-shotcrete support, the unsymmetrically loading, water and etc. affect on the stability of surrounding rock. Bolt ant shotcreting restrict very much the deformation and the plastic zone. Because of terrains the unsymmetrically loading has an important effect on induced stress field of surrounding rock. So the bias tunnel makes a great difference in the stress field and plastic zone of surrounding rock. The shallow-burial of the tunnel directly changes the stress field of surrounding rock and affects the stability of sidehill. The groundwater makes a very adverse effect on the tunnel with shallow-depth.更多还原