滑坡隧道与抗滑桩相互作用机理研究及数值模拟

发布时间：2018-04-29 22:18

本文选题：滑坡隧道 + 抗滑桩与隧道结构的间距　；参考：《北京交通大学》2014年硕士论文

【摘要】：在偏远山区修建的公路,往往以隧道的形式穿越山体斜坡。当这些斜坡出现滑坡现象时,斜坡与隧道将会产生轻重不同程度的病害,严重时可能中断线路。在利用抗滑桩治理该类病害问题时,若抗滑桩与隧道结构的间距太小,抗滑桩对隧道产生挤压作用,增加了作用于隧道结构上的滑坡推力；若间距太大,抗滑桩与隧道结构之间的土体可能会形成二次滑坡,同样对隧道危害很大,可见抗滑桩与隧道结构的间距是滑坡隧道整治成败的关键因素之一,而其对隧道与滑面的相对位置关系十分敏感,针对这一问题,本文开展了滑坡、隧道和抗滑桩相互作用机理的研究工作,分析了抗滑桩与隧道结构的间距对隧道与滑面相对位置关系变化的敏感度。本文在前人研究的基础上将隧道与滑面的相对位置关系划分为：隧道与滑面相交、隧道位于滑面之上和隧道位于滑面之下,并抽象出与之相对应的隧道结构的力学模型：侧向剪切型、坐船顺滑型和拱顶扰动型。结合具体的工程实例,针对隧道在不同的力学模型中的受力情况,分析了隧道的变形特征,为反分析时根据隧道的变形特征判断滑面的具体位置提供了一定的理论依据。在此基础上,建立了三维有限元模型,通过计算边坡的安全系数和隧道衬砌结构变形两个指标,分析了抗滑桩与隧道结构的间距对隧道与滑面相对位置关系变化的敏感性。经分析计算结果,主要得出以下几点结论： (1)当隧道位于滑面下方时,滑坡对隧道结构的影响最小,抗滑桩与隧道结构的间距对相对位置关系的敏感性最低,在治理时以滑坡整治为主,控制隧道变形为辅； (2)当隧道与滑面相交时,滑坡对隧道结构的影响较大,隧道结构受到滑体与基岩的剪切作用,同时隧道又像一根扁长型的空心抗滑桩,对滑坡具有一定的抗滑作用,因此,在治理时要充分考虑隧道结构的抗滑功效。抗滑桩与隧道结构的间距对这种位置关系比较敏感,治理此类病害问题时,应通过优化对比,确定最佳的抗滑桩与隧道结构的间距； (3)当隧道位于滑面上方时,滑坡对隧道结构的影响最大,严重时滑坡体内外的隧道可能产生错断。抗滑桩与隧道结构的间距对这种位置关系最敏感,选择不当,抗滑桩与隧道之间的土体可能形成二次滑坡,对隧道结构的危害很大。因此在治理时要充分考虑抗滑桩与隧道之间的桩土力学效应,以求达到最佳的治理效果。最后用具体的工程实例验证了数值分析的正确性及实际工程处治的可行性。并提出了针对滑坡地段隧道变形病害整治的工程措施,为今后工程管理部门在治理类似的工程问题时提供一定的理论依据和参考意见。
[Abstract]:Roads built in remote mountain areas often tunnel through mountain slopes. When these slopes appear landslide phenomenon, the slope and tunnel will produce different degrees of disease, and if serious, the line may be cut off. If the distance between the anti-slide pile and the tunnel structure is too small, the anti-slide pile can squeeze the tunnel and increase the landslide thrust acting on the tunnel structure, if the distance is too large, The soil mass between the anti-slide pile and the tunnel structure may form a secondary landslide, which is also harmful to the tunnel. It can be seen that the distance between the anti-slide pile and the tunnel structure is one of the key factors for the success or failure of the landslide tunnel regulation. However, it is very sensitive to the relative position of tunnel and sliding surface. In view of this problem, the mechanism of landslide, tunnel and anti-slide pile is studied in this paper. The sensitivity of the distance between anti-slide pile and tunnel structure to the relative position of tunnel and sliding surface is analyzed. On the basis of previous studies, the relative position relationship between tunnel and sliding surface is divided into three parts: tunnel intersecting with sliding surface, tunnel located above sliding surface and tunnel below sliding surface. The corresponding mechanical models of tunnel structure are abstracted: lateral shear type, boat slippery type and dome disturbance type. Combined with the concrete engineering examples, the deformation characteristics of the tunnel are analyzed according to the stress situation of the tunnel in different mechanical models, which provides a certain theoretical basis for judging the concrete position of the sliding surface according to the deformation characteristics of the tunnel in the back analysis. On this basis, a three-dimensional finite element model is established. By calculating the safety factor of slope and the deformation of tunnel lining, the sensitivity of the distance between anti-slide pile and tunnel structure to the relative position of tunnel and sliding surface is analyzed. The main conclusions are as follows: 1) when the tunnel is located below the sliding surface, the landslide has the least influence on the tunnel structure, and the distance between the anti-slide pile and the tunnel structure has the lowest sensitivity to the relative position relationship. 2) when the tunnel intersects with the sliding surface, the landslide has a great influence on the tunnel structure. The tunnel structure is shearing by the sliding body and the bedrock. At the same time, the tunnel is like a long flat hollow anti-slide pile, which has a certain anti-slide effect on the landslide. The anti-slip effect of tunnel structure should be fully considered in the treatment. The distance between anti-slide pile and tunnel structure is sensitive to this kind of position relation. When dealing with this kind of disease, the optimum distance between anti-slide pile and tunnel structure should be determined by optimizing comparison. 3) when the tunnel is located above the sliding surface, the landslide has the greatest influence on the tunnel structure, and the tunnel inside and outside the landslide body may be faulted when serious. The distance between the anti-slide pile and the tunnel structure is the most sensitive to this kind of position relationship. The soil between the anti-slide pile and the tunnel may form a secondary landslide which is very harmful to the tunnel structure. Therefore, the pile soil mechanics effect between the anti-slide pile and the tunnel should be fully considered in order to achieve the best treatment effect. Finally, the correctness of numerical analysis and the feasibility of practical engineering treatment are verified by concrete engineering examples. The paper also puts forward the engineering measures for the treatment of tunnel deformation diseases in landslide section, which provides certain theoretical basis and reference advice for the engineering management department in the future in the treatment of similar engineering problems.
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U457.2;U452.11

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