苏锡常地区第四纪地层工程地质精细化分析研究

The quaternary soil in Su-Xi-Chang land subsidence area will be studied in this project. The soil structure of every individual layer in multi scales will be delicately analyzed with the aim to obtain several tables of typical profiles with delicate analysis results. The soil deformations in several boreholes in this area will be monitored by using distributed fiber sensing technologies (BOTDR and FBG). The relationships between the soil structures and the soil deformation behaviors will be built based on the laboratory tests of soil deformation behaviors, the field monitoring data of soil deformation and the delicate analysis results of the soil structure. The contribution of each soil layer to the land subsidence in Su-Xi-Chang area will be identified and the deformation trend of each layer will also be explored. Finally, a better understanding of the land subsidence mechanism in this area will be provided. This project is of great significance in the protection of the urban geological environment and the scientific planning of engineering activities in Su-Xi-Chang area.

本项目以苏锡常地面沉降区第四纪土体为研究对象，从不同结构尺度对各地层土体的结构特征展开精细化分析，并汇总获得该地区若干典型剖面土体结构精细化分析成果表；运用分布式光纤感测技术(BOTDR和FBG)对各地层土体变形进行现场监测，结合室内试验中土体变形特性和精细化分析获得的土体结构参数，揭示土体结构-土体变形相互协调关系；精确揭示苏锡常地区不同土层对地面沉降的贡献，并判断各地层变形的发展趋势，为该地区地面沉降发生机理提供一个新的认识。本项目研究结果对苏锡常地区的城市地质环境保护和科学规划工程建设具有重要意义。

本项目紧紧围绕“苏锡常地区第四纪地层工程地质精细化分析研究”这一中心课题，主要以苏锡常地面沉降沉降区第四纪土体为研究对象，开展了土体结构精细化分析；采用现场分布式光纤监测与室内试验相结合的方式，深入探讨了地面沉降过程中不同类型土的微观结构演化特征，为地面沉降机理和变形潜力评价提供了新的思路和方法。项目取得了一批创新成果：（1）从多尺度对苏锡常地区第四纪土体工程地质性质进行了精细化分析；（2）掌握了土体变形过程中微观结构定量化特征，以及不同因素对土体变形过程的影响；（3）提出并应用了地面沉降分布式光纤监测技术，获得了苏锡常、江苏沿海等地区地面沉降钻孔中土体变形分布规律和演化过程；（4）掌握了土体微观结构参数与土体压缩变形的关系，为深入阐述地面沉降机理提供了依据；（5）提出基于土体微观结构特征的地面沉降潜力评价方法。本项目的研究对于深入了解土体变形过程、开展地面沉降监测与防治具有重要意义。