公路双连拱隧道开挖方法及施工过程数值模拟研究

【作者】 王文正；

【导师】 夏永旭；

【作者基本信息】 长安大学 ， 桥梁与隧道工程， 2003， 硕士

【摘要】 本文首先系统地论述了国内外公路双连拱隧道常见的结构断面形式和开挖方法。探讨了应用平面应变模型进行隧道施工过程模拟的常用方法，在“反转应力释放法”的基础上，结合ANSYS软件可以模拟连续施工的特点，提出利用“施加虚拟支撑力逐步释放法”来实现隧道施工过程中地应力随工序的逐步释放的思路，并且利用ANSYS的APDL设计语言，开发出施加虚拟支撑力的命令，实现了施工过程中应力的逐步释放，从而找到了一种模拟隧道施工过程的好方法。对实际工程中最常用的三种开挖方法分别进行了施工模拟，分析了它们各自的围岩和支护的受力变形规律，经比较后，得出了三导洞法是Ⅱ类围岩中修建连拱隧道的较好开挖方法的结论。并对“三导洞法”进行连拱隧道施工时围岩和结构的受力变形规律进行了详细分析，同时模拟了施工中的不利因素、应力释放系数和二次衬砌施作等的影响。接着对连拱隧道进行了平面弹塑性模拟分析，得到了施工过程中塑性区出现的位置和规律，提出了防止因塑性变形过大而引起坍塌的强度补救措施，并应用数值模拟方法检验其效果。最后建立了三维空间模型，对连拱隧道开挖时的空间效应、左右洞的相互影响，以及中隔墙的变形和稳定性进行了模拟分析。 本文通过对ANSYS软件进行适当的开发，找到了进行隧道施工模拟比较理想的方法，将之与工程师的工程经验相结合，必能对隧道等地下工程的设计和施工起到促进和帮助作用。所得结论对公路双连拱隧道的建设有重要的工程指导意义。更多还原

【Abstract】 In this paper we dissertate the common structure cross forms and excavating methods of highway double-arc tunnel home and abroad at the first part, and study common simulation methods of tunnel construction afterwards. Based on the method of reversing and releasing the stress, and combined with the capacity of simulating continuous construction of ANSYS programme, we come up with the thought of using the method of applying virtual support force to release the stress step by step to realize the step-by-step release of initial stress during the tunnel construction simulation. With the help of design language of ANSYS, we develop a command to apply the virtual support force. Then we simulate the common excavating methods of double-arc tunnel respectively, analyze the stress and strain of wall rock and support structure of each method, and recommend the best excavating method to construct double-arc tunnel in wall rocks of II .Then we analyze the "three headings method" in detail, and also simulate the effect of construction factor, stress releasing coefficient and secondary lining. Then we carry out plane elastoplastic simulation of double-arc tunnel, and get the development regularity of plastic region. Finally we set up three-dimensional space model to simulate the space effect during tunnel construction, analyze the transaction between the left runnel and the right tunnel, and also analyze the deformation and stability of mid-partition.We get an ideal method to tunnel construction simulation through proper development of ANSYS programme in this paper. Combined with the experience of engineers, it can benefit and accelerate the design and construction of tunneling projects. The conclusions we draw can also play a directive role in highway double-arc tunnel construction.更多还原