云南丽江S220公路片理化岩体边坡破坏机理研究

发布时间：2018-05-29 01:02

本文选题：片理化 + S220公路　；参考：《中国地质大学(北京)》2017年硕士论文

【摘要】：云南地区地质构造复杂,地质灾害频发,其中由边坡破坏造成的滑坡崩塌危害最大。通过对云南省宁蒗县与永胜县之间的S220公路的地质调查,发现在两县分界处的边坡岩体普遍片理化,且滑坡较多。片理化带中“片理”对公路边坡破坏起着控制作用。该段公路为三层的盘山公路,公路宽度4米左右,而且地形复杂,海拔达2500米以上,经常发生滑坡容易造成交通中断。因此选取该公路边坡作为研究对象,开展了野外地质调查、坡面测绘、滑坡统计等工作。对边坡进行实地调查发现,调查区边坡发育两组到三组“片理”。在同一段边坡中“片理”的产状大致一致,具有规则性。同时在泥质含量高的边坡岩体中发育密集“片理”,“片理”面间距小于5厘米,而在泥质含量低的边坡岩体中“片理”面间距大于5厘米。片理化导致边坡岩土体结构发生破坏,成为碎裂结构或散体结构,使其整体强度大大降低。具有片理化特征的边坡,其破坏往往从边坡发育“片理”的位置开始发生变形破坏,加速了边坡的破坏进程,成为控制边坡岩体强度和边坡的发展变形和破坏的主要因素。在研究区选取典型边坡进行测量,对其“片理”产状进行赤平投影,分析造成边坡破坏的优势结构面,并利用Flac3D采用强度折减法对片理化岩质边坡进行应力、应变分析,得到边坡岩体的应力分布及变形特征以及可能发生破坏的部位。发现“片理”产状对剪应变增量的影响较大,当“片理”产状与坡面倾向一致时,倾角的大小影响破坏的部位,倾向影响边坡开挖后出现破坏的部位。并结合当地的地层岩性、气候和边坡工程地质条件总结该地区片理化边坡破坏过程。
[Abstract]:The geological structure is complex and geological disasters occur frequently in Yunnan area, in which landslide collapse caused by slope failure is the most harmful. Through the geological investigation of the S220 highway between Ninglang County and Yongsheng County, Yunnan Province, it is found that the slope rock mass at the boundary of the two counties is generally physical and chemical, and there are more landslides. In the sheet physical and chemical belt, the "slice" plays a controlling role in the highway slope damage. This section of the highway is a three-story Panshan highway with a width of about 4 meters and complex topography, which is over 2500 meters above sea level. It is easy to cause traffic disruption due to landslides. Therefore, the highway slope is selected as the research object, and the field geological survey, slope mapping, landslide statistics and so on are carried out. The investigation shows that there are two to three groups of slope in the investigation area. In the same section of slope, the occurrence of "slice" is roughly consistent and regular. At the same time, dense "lithology" is developed in the slope rock mass with high muddy content, the spacing of the "schist" plane is less than 5 cm, while in the slope rock mass with low muddy content, the "laminae" plane spacing is more than 5 cm. Sheet physicochemical analysis results in the failure of rock and soil structure, which results in a fragmentation structure or a granular structure, which greatly reduces the overall strength of the slope. The failure of slope with sheet physical and chemical characteristics often occurs from the position where the slope develops "slice", which accelerates the failure process of slope and becomes the main factor to control the strength of slope rock mass and the development of deformation and failure of slope. In the study area, the typical slope is selected to measure, the "slice" occurrence is projected, the dominant structural plane is analyzed, and the stress and strain analysis of the sheet rock slope is carried out by using the strength reduction method of Flac3D. The stress distribution and deformation characteristics of the slope rock mass and the possible site of failure are obtained. It is found that the occurrence of "gouge" has a great influence on the increment of shear strain. When the occurrence of "gouge" is consistent with the slope inclination, the angle of inclination affects the site of failure and the position of slope failure after excavation. Combined with the local stratigraphic lithology, climate and slope engineering geological conditions, the damage process of the slope in this area is summarized.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U416.14

【相似文献】