深季节冻土区高铁建设运行下膨胀岩滑坡防控分析理论与评估方法

This proposal is motivated by the development of the high speed railway in cold regions. This work emphasizes the two coupling effects directed against the artificial swelling rock cutting slope in the alpine deep seasonally frozen environment, by relying on Jilin-Tumen-Hunchun High-speed Rail and Harbin-Jiamusi High-speed Rail. The coupling effects include the dry-wet cycle and the excavation disturbance during the high-speed rail construction period and the freezing-thawing cycle, dry-wet cycle and the travelling vibration during the operative period. Themes which are to be addressed include the behavior variation and degradation of the swelling rock induced by the excavation unloading and travelling vibration during under-going dry-wet cycle, the cutting slope deformation and failure modes and landslide cataclysm, and the critical technologies and measure fundamentals for the landslide prevention and control. This proposal will explore the integrated research method of the consulting and investigation, field survey, test detection, in-situ monitoring associated with the theoretical analysis, numerical simulation and the example verification. Finally, it is expected that through the efforts this proposal will achieve to solve problems covering the: (1) Degradation evolution and failure rules for swelling rock behavior. (2) Slope deformation failure mechanism and stability analysis method. (3) Slope response laws and analysis method induced by travelling vibration. (4) Analysis theory and evaluation method for landslide prevention and control. This project ultimately benefits for understanding the deformation and cataclysm laws of the swelling rock slope and the fundamental measures and theories for landslide prevention and controlling induced by the multi-coupling effects in the alpine deep seasonally frozen environment. Most importantly, it aims to improve the research level and to strengthen the emergency capability of the co-management of prevention and control for geological landslide hazard during the construction and operation periods of the major project in the special alpine soft rock environment.

基于我国寒区高铁发展工程背景，针对高寒深季节冻融环境膨胀岩人工路堑边坡，依托吉林－图们－珲春高铁、哈尔滨－佳木斯高铁，注重高铁建设期干湿循环－开挖扰动耦合作用、运行期冻融循环－干湿循环－行车振动耦合作用，聚焦在冻融循环－干湿循环条件下膨胀岩随开挖卸荷、行车振动而发生性能变化与劣化，边坡变形失稳、破坏模式与滑坡灾变，以及滑坡防控的技术关键与措施原理，着眼咨询调研、实地调查、试验检测、现场监测与理论分析、数值模拟、实例验证等相结合的研究方法，致力研究解决深季节冻融环境多因素耦合作用下膨胀岩性能劣化演变与破坏规律、边坡变形失稳机制与稳定性分析方法、边坡行车振动响应规律与分析方法、滑坡防控分析理论与评估方法。有利于认识高寒深季节冻融环境多因素耦合作用下膨胀岩边坡变形灾变演化与滑坡防控的根本途径、措施原理，并加强高寒区特殊软岩重大工程建设运行滑坡地质灾害防控的研究水平与联动处理的应急能力。

基于我国寒区高铁发展工程背景，针对高寒深季节冻融环境膨胀岩路堑边坡，依托吉林－图们－珲春(吉图珲)高铁、哈尔滨－佳木斯(哈佳)高铁，注重高铁建设期干湿循环－开挖扰动耦合作用、运行期冻融循环－干湿循环耦合作用，聚焦在冻融循环－干湿循环条件下膨胀岩随开挖卸荷而发生性能变化与劣化，边坡变形失稳、破坏模式与滑坡灾变，以及滑坡防控的技术关键与措施原理。主要研究深季节冻融环境多因素耦合作用下膨胀土力学特性演化规律、高寒深季节冻土区高铁膨胀土边坡－板桩墙－路堑体系监测系统建立及深季节冻融环境多因素耦合作用下膨胀岩边坡稳定性和滑坡防控分析。研究进展如下：.(1) 通过膨胀土冻融宏细观力学特性试验、蠕变与应力松弛试验和冻胀变形试验，分析了冻融循环作用下膨胀土细观结构与宏观力学特性劣化演变规律，探究了冻融循环对膨胀土长期力学性能影响规律，系统分析了膨胀土的冻结温度、试样断面温度演化规律、试样水分重分布、冷生构造、冻胀融沉变形和状态路径等。在试验基础上，构建了基于广义塑性理论的冻融饱和膨胀土弹塑性本构模型，提出了膨胀土冻胀力学模型及变形分析方法。.(2) 依托哈尔滨－佳木斯客运专线，在哈尔滨市宾西镇建立了深季节冻融环境膨胀岩边坡－路基现场监测示范平台，获取随季节变化膨胀土边坡全深度的水平位移变化规律。此外，在吉珲铁路客运专线延吉段、哈佳高速铁路宾西段与佳木斯市东风段、南阳内邓高公路师岗段等4个典型场地开展原位试验区，在高密度电法试验基础上，开展了现场自钻式旁压试验、预钻式旁压试验、孔内剪切试验与扁铲侧胀试验等，取得了场地原位力学特性第一手宝贵资料。.(3) 依托吉图珲高铁典型段膨胀岩路堑边坡，建立了考虑冻融循环作用膨胀岩路堑边坡―板桩墙支护体系三维有限元模型，研究开挖扰动、降雨和融雪入渗条件及冻融循环作用对膨胀岩路堑边坡稳定性影响，探究了开挖扰动及冻融循环作用对板桩墙支护结构性能影响规律。此外，针对目前工程中一般采用矩形截面的桩板墙和新型(采用圆形截面桩)桩板墙，采用强度折减法求解路堑开挖后桩板墙体系提供的边坡安全系数，以此对比分析桩板墙支护性能的优劣，探讨圆形桩―板墙体系应用于实际工程的可能性。.研究工作有利于认识高寒深季节冻融环境多因素耦合作用下膨胀岩边坡变形灾变演化与滑坡防控的根本途径、措施原理，并加强高寒区特殊软岩重大工程建设运行滑坡地质灾害防控的研究水平与联动处理的应急能力。