【作者】 马琳；

【导师】 白明洲；

【作者基本信息】 北京交通大学 ， 地质资源与地质工程， 2016， 硕士

【摘要】 随着油气管道建设的高速发展,地质灾害对管道建设及运营的影响日益突出。长输油气管道因其站多、线长、面广的工程特点,几乎穿越了所有地质灾害类型区,其中包括山区、丘陵区、黄土分布区、岩溶发育区等。中缅油气管道穿越西南部云贵川地区,沿线地质环境条件和自然地理条件复杂多样,是我国地质灾害高发地段,在管道建设运营过程中不可避免地受到地质灾害的威胁、危害。因此本文依托于中缅油气管道工程,对该长输管道沿线典型高陡滑坡进行稳定性研究是非常有意义的。研究区内滑坡的共同特点是：高陡既有滑坡进行横坡开挖,并且受暴雨、地震影响较大。本文选取基于强度折减法的有限元软件GTS进行合理分析,得出了管道沿线滑坡稳定性研究的一般规律,对现场监测预警系统起到一定的辅助作用。研究主要内容包括：(1通过中缅管道沿线滑坡的自然地理条件、地形地貌、地层岩性、地质构造等特征研究,分析了滑坡的类型、分布、规模等特征。根据其岩土体组成不同,将滑坡分为土质滑坡和岩土混合质滑坡；根据坡度不同,分为一类滑坡(150-190),二类滑坡(20°-29°),三类滑坡(300-35°),此分类方式用于地震工况研究.(2)通过数值模拟研究,分析了自然、开挖、支护三种工况下滑坡的稳定性特征,包括横坡开挖条件下滑坡稳定性变化情况和最大位移发生的位置。自然状态下最大位移在滑坡前端局部坡度较大处：施工开挖后,最大位移点转移至临空面(3)结合有限元数值模拟,研究了滑坡变形破坏的控制性因素和变形量之间的关系和规律特征。研究发现：岩土混合质滑坡稳定性系数为1.2时,对应变形量平均值为5.66mm；稳定性系数为1.0界限值时,变形量平均值为8.88cm。以此可作为地表位移监测系统的预警判别值,若监测到现场地表位移超过8.88cm时,滑坡应判别为临近破坏,应及时进行治理。(4)通过暴雨和地震工况下滑坡稳定性特征研究发现：一类滑坡K=1时,可承受地震力加速度平均值为0.3g；二类滑坡K=1时,可承受地震力加速度平均值为0.08g；三类滑坡K=1时,可承受地震力加速度平均值为0.038g。计算得出不同水位情况下安全系数,现场可通过水位线监测结果,判别滑坡稳定性情况。更多还原

【Abstract】 With the rapid development of oil and gas pipeline construction, the influences of geological hazards on construction and operations of pipeline become increasingly serious. Due to the characteristics of multi stations, line length, and wide ranges of engineering, long distance oil and gas transmission pipeline almost cross the region which includes almost all types of geological disasters, including mountains, hills, loess, karst developing area. China and Myanmar oil and gas pipelines cross Southwest area, such as Yunnan, Guizhou and Sichuan. The geological and geographical conditions are complex and varied along pipelines. These areas are high-occurrence disaster zone for landslides. During the construction, there are inevitable disasters and harm. Therefore, this paper makes a study on stability of the long distance pipelines along the typical high slope, this study is very meaningful.The common characteristics of the slope in the study are:lateral excavation of high slope, big impact of heavy rain and earthquake. In this paper, the finite element software GTS based on the strength reduction method is chosen to do the reasonable analysis. It gives the general rules of the stability of the slope along the pipelines and plays an auxiliary role in the field monitoring and early warning system. The main contents of the study include:(1) It make the study of the natural and geographical conditions, topography, stratum and lithology, geological structure characteristics of slopes of the China-Myanmar pipelines, analyze of the slope types, distribution, sizes and other characteristics. According to the rock and soil composition, the slopes can be divided into soil slopes and rock-soil mixed slopes; According to the grades of slopes, slopes can be divided into first class slope (15°～19°), second slope (20°～29°) and third slope (30°～35°)。(2) Due to the numerical simulation, this paper makes the research of the stability characteristics of the slope under three kinds of construction conditions, which are nature, excavation and support. Research shows that under the condition of the excavation of horizontal slope is maximum displacement position when the high slope stability changes; Under natural state, the maximum displacement is at the front of the slope whose slope is larger; After excavation, the maximum displacement point transfer to critical surface.(3) Combined with the finite element numerical simulation, this paper analyze the relationship between the control factors of slope deformation damage and the amount of slope deformation. The study found that when the stability coefficient of the rock and soil mixed slope is 1.2, the average value of the corresponding deformation is 5.66mm; When the stability coefficient is 1.0 boundary value, the average value of the deformation is 8.88cm. It can be regarded as the advanced warning discriminant value of ground displacement monitoring system, if the monitoring to the ground surface displacement is more than 8.88cm, the slope should be judged to be nearly damaged, should be timely treatment.(4) Through the analysis of the heavy rain and earthquake conditions characteristic of the slope stability, it indicates that, when first slope K=1, the withstand earthquake acceleration average value is 0.3g:When second slope K=2, the withstand earthquake acceleration average value is 0.08g; When second slope K=3, the withstand earthquake acceleration average value is 0.038g. The safety factor is calculated under different water level, and the field can be monitored by the water level line to determine the stability of the slope.更多还原