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题名	典型加固边坡地震动土压力计算与永久位移预测
作者	王娟
学位类别	硕士
答辩日期	2014
授予单位	中国科学院研究生院
授予地点	北京
导师	何思明
关键词	挡墙结构 拟动力法 动土压力 永久位移
其他题名	Earth pressure calculation and permanent displacement forecast of typical reinforced structure under seismic loading
学位专业	防灾减灾工程及防护工程
中文摘要	随着我国西部地区城镇化的快速发展，基础设施建设过程中形成了大量的人工边坡，为了确保边坡的安全性，常常需要对边坡进行加固处理。挡墙作为一种经济、有效的边坡支护结构，被大量的运用于公路、铁路、水电工程、路基工程中。由于西部地区地质环境脆弱，构造复杂，地震频发，因此在边坡设计工程中加入抗震设计具有很重要的意义。基于此，本文选取两种挡墙结构形式，采用极限平衡法、极限分析法以及拟动力法研究了在地震荷载作用下加固结构的地震特性，再结合Newmark理论得到了边坡支护结构在地震荷载作用下产生的永久位移值，为边坡抗震设计提供了一个新的思路。 传统的地震永久位移和地震土压力的计算方法中，地震荷载作用被看作是一个大小方向固定的惯性力作用，但是大量试验研究表明，地震荷载作用是随时间和空间不断发生变化的。因此采用拟静力法来计算边坡的永久位移以及地震土压力就存在一定的缺陷，基于此，本文采用拟动力学的方法，将地震荷载作用看作是沿高度和时间分布的正弦函数，以此来研究加固结构的永久位移以及地震土压力。 采用极限平衡方法以及拟动力学的方法，研究了重力式挡墙在地震荷载作用下的主动土压力的具体分布形态，并且研究了超载对于主动土压力分布以及合力作用点位置的影响。所得的结果与前人的结果进行分析比较，证明该方法的合理性。并揭示了个参数对于挡土墙土压力分布、主动土压力合力作用点高度以及破裂角大小的影响。 在挡土墙主动土压力分布的基础之上，研究了挡土墙在地震荷载作用下的屈服加速度的表达式，并且得到了挡土墙永久位移的计算方法。挡土墙地震永久位移主要分为两个部分，第一是挡土墙由于平动产生的永久位移，第二是绕墙趾转动产生的永久位移。计算结果表明，在相同的地震条件下，挡土墙更易发生倾覆破坏导致结构失效。 运用极限分析上限定理，建立加筋土挡墙在地震荷载作用下的功能表达式，当外力功率与内能耗散相等的时候，边坡处于极限状态，此时对应的地震加速度为屈服加速度，超过屈服加速度的部分将会产生永久位移，当地震加速度低于屈服加速度，边坡再次处于平衡状态。经过计算可以确定边坡潜在破裂面的形状，以及在地震作用下的永久位移的值，并且将拟静力法与拟动力法的计算结果进行分析比较，阐述两种方法的优缺点。
英文摘要	Along with the development of urbanization in China's western region, a lot of artificial slope are formed in the process of infrastructure construction. In order to ensure the safety of the slope, the reinforced structures need to be build. As a kind of economic and effective slope supporting structures, retaining wall structures are widely used in highway, railway, water and electricity engineering and subgrade engineering. The geological environment in western region is fragile, complex and instability under the earthquake. So, it is important to take the earthquake action into consideration during the design of slope engineering. Based on this, the article selects two kinds of retaining wall structure forms to study the seismic properties of strengthening structure under earthquake load using the limit equilibrium method, the limit analysis and the pseudo dynamic method. And then, the article coupled with Newmark theory to obtain the permanent displacement of the reinforced slope structure under earthquake load. Above all, a new direction is proposed for the slope seismic design. The earthquake load is regarded as a fixed size direction inertia force in the traditional calculation methods. But a large number of experimental study show that, the seismic load is constantly changing with time and space. So the pseudo-static method is adopted to calculate the slope of the permanent displacement and seismic earth pressure has certain defects. Based on this, the article adopts the pseudo-dynamic method which regarded earthquake load as a sine function along the height and time. Then can obtain the permanent displacement and earth pressure of the reinforced structures. Using limit equilibrium method and the pseudo-dynamic method to study the distribution of active earth pressure of gravity retaining wall under seismic load. And study the effect of active earth pressure distribution and resultant force point position on overload. Compared the results with the predecessors', it proves the method in this dissertation is reasonable. The article reveals the parameters how to effect the earth pressure distribution, the resultant force point height and angle of rupture. Based on the active earth pressure distribution of retaining wall, the expression of the yield acceleration and the permanent displacement of retaining wall under seismic load are studied. Seismic permanent displacement of the retaining wall is composed of two parts, the one is caused by horizontal movement under the earthquake, and the other is spinning around the wall toe. The results show that retaining wall is more likely to occur overturn failure under the seismic conditions. According to the upper bound theorem of limit analysis, the energy formula is established to calculate the yield acceleration of reinforced soil retaining wall under earthquake load. When the external work is equal to internal energy dissipation, the yield acceleration could be obtained. The earthquake could produce a permanent displacement when the seismic acceleration beyond the yield acceleration. And the slope will in balance again when the seismic acceleration below the yield acceleration. Then the potential failure surface of the slope and the value of the permanent displacement under seismic action could be calculated. Compared the calculating results with pseudo-static method and pseudo-dynamic method, it is verified that the presented method is reasonable and has priority to traditional analysis method in precision.
语种	中文
内容类型	学位论文
源URL	[http://ir.imde.ac.cn/handle/131551/8020]
专题	成都山地灾害与环境研究所_山地灾害与地表过程重点实验室
推荐引用方式 GB/T 7714	王娟. 典型加固边坡地震动土压力计算与永久位移预测[D]. 北京. 中国科学院研究生院. 2014.

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