成都平原地质条件及岩土工程勘察问题分析

Analysis of Geological Conditions of Chengdu Plain and Problems in Geotechnical Investigation

成都平原位于龙门山和龙泉山两山之间的地带,位于青藏高原东南侧前缘的第四纪断陷盆地,它是从大邑-彭州市-绵竹隐伏断陷和浦江-新津-成都-德阳断裂所夹的北东向开始,然后往东西向扩展。在其地貌发展过程中,龙门山推覆构造带的逆冲推挤作用、河流的冲刷作用和沉积起到重要作用。根据成都平原各类岩土工程勘察资料,发现平原与山地地区建筑工程地质条件存在明显差异。为提供拟建建筑场地的适宜性,采取多种方法勘察场地的工程地质条件,对拟建场地地基稳定性和存在的困难作出初步评价,对平原地区存在不良地质作用进行防治,对基础形式、基础埋深、地基处理等方案的选择提出了合理化建议。

Chengdu Plain is located in the zone between Longmen Mountain and Longquan Mountain.It is a Quaternary fault basin in the southeast front of the Qinghai Tibet Plateau.It starts from the northeast direction between the concealed fault depression of Dayi–Pengzhou-Mianzhu and the Pujiang–Xinjin–Chengdu-Deyang fault,and then extends to the east-west direction.In the process of its geomorphic development,the thrust and compression of the Longmen Mountain nappe structural belt,as well as the erosion and sedimentation of rivers,play an important role.According to various geotechnical investigation data of Chengdu Plain,it is found that there are obvious differences in the construction engineering geological conditions between the plain and mountainous areas.In view of the suitability of geotechnical investigation for the proposed construction site,various methods are adopted to investigate the engineering geological conditions of the site,make a preliminary assessment of the stability of the foundation of the proposed site and the existing difficulties,prevent the adverse geological effects in the plain area,and control the foundation form,foundation burial depth,and provide reasonable suggestions for the selection of foundation treatment and other plans.