强夯振动引起黄土滑坡机理研究

This subject will take the landslides from the under building airport engineering and removing hills and filling gullies engineering in the development of some new city area as samples for further analysis. In this research, adequate consideration will be given to traits of dynamic compaction which are large-tonnage, multi-cycle and long-duration. Firstly, we plan to put the dynamic transducers in the loess to receive the time history curve of vibration acceleration caused by dynamic compaction. Secondly, the curve will be applied to the loess samples which collected form slide zone on the GDS dynamic triaxial test system for research of strength and deformation traits of loess in slide zone. At the same time, the curve will also be input to dynamic FEM model to take analog computation of the overall process form deformation, failure to slide. Then,cooperating with the monitoring of deformation of loess landslides by multiple position extensometer and gradiograph to get the curve of deformation, after that, the data will be applied to explain the influence of vibrating load of dynamic compaction.It is analyzed that the influence of single dynamic compaction and the vibration superposition of dynamic compaction in crow on the stability of loess landslide. Based on above, according to the principle of soil dynamics, plastic mechanics and variations to make quantitative analysis of the formation mechanism and deformation mechanism of the landslides. Then, we will analyze the formation, evolution and failure mechanic principle of the slide surface and research the mechanic theory of the landslides in every process and stage. Besides, we will find the relationship between dynamic load and the deformation critical value of the loess in slide zone. Moreover, to deduce the formula of the landslides` movement locus, speed and distance. Finally, all works will be checked by in-situ examples. These works will lead us get new knowledge of this kind of landslides and provide new theoretical basis to landsliede provention.

本申请课题拟以黄土高原山区新建机场、新城的移山填沟周边黄土滑坡实例为解剖对象，充分考虑强夯大吨位、多重复和长持时的振动荷载特点。在现场埋设各种动力传感器，接收强夯振动的加速度时程曲线，经处理后再将这种"大吨位、多重复和长持时"振动的特殊荷载施加于动三轴来研究滑带黄土的强度、变形等特点，并将其输入动力数值模拟模型计算模拟黄土滑坡变形、破坏、滑动的全过程，分析单夯和群夯叠加而产生的振动波对黄土滑坡稳定性的影响。在此基础上，按照土动力学、塑性力学和变分等原理定性定量分析此类滑坡的形成机理和运动机理，如滑面的形成和演化、滑坡破坏模式、滑坡的发育过程和阶段符合什么力学原理，动荷载与滑带土变形破坏临界值有什么关系；滑坡滑动轨迹、滑速和滑距等运动特征公式的推导等；最后用实例加以验证。这将对此类滑坡的机理有一全新的认识，并为其防治提供新的理论依据。

本项目按预期计划在2017年12月如期完成。2014年1月开始着手全面收集整理资料并全面开展工程地质勘察工作等一系列的工作，2014年12月展开了室内试验，后面的工作都按照原计划进行。因此，截止2017年12月整个项目都是按原年度研究计划进行着并如期完成。.本项目以黄土高原山区新建机场、新城的移山填沟周边黄土滑坡实例为解剖对象，经过系统、深入的研究，阐明了滑带黄土在强夯大吨位、多重复和长持时的这种特殊振动荷载作用下的强度、变形特点；建立了特殊荷载作用下的黄土滑坡变行、破坏、滑动的全过程动力数值模拟计算模型；揭示了单夯和群夯叠加而产生的振动波对黄土滑坡稳定性的影响规律；定性定量分析此类滑坡符合的力学机理以及动荷载与滑带土变形破坏临界值之间的关系；推导了滑坡滑动轨迹、滑速和滑距等运动特征公式。本项目的研究提出了强夯振动这种“大吨位、多重复和长持时”的特殊振动荷载引起的黄土滑坡发育机理，为此类滑坡的防治提供新的理论依据，有着重要的现实实际意义和理论指导意义。.研究成果是以论文、专著、学术会议交流及实用专利形式提供的。其中，在国内和国际核心期刊已发表论文（含已录用）29篇，其中SCI检索2篇，EI检索5篇；参加国际学术会议1次；获得实用专利12项，其中发明专利5项，实用新型专利7项，出版学术专著一部；获得陕西省科技进步奖2项；培养硕士研究生15人，博士研究生5人，博士后1人。