相邻深基坑开挖相互影响的三维性状分析  

Three-Dimensional Analysis of Interaction Between Adjacent Deep Excavations

作　　者：李锦 LI Jin(Shanghai Urban Construction Design&Research Institute(Group)Co.Ltd.,Shanghai 200125)

机构地区：[1]上海市城市建设设计研究总院(集团)有限公司,上海200125

出　　处：《土工基础》2024年第5期739-745,共7页Soil Engineering and Foundation

摘　　要：在城市地下工程建设中,相邻基坑工程频繁出现,与独立基坑工程相比,相邻基坑开挖的相互作用对基坑支护结构和周围土体产生影响,使支护结构的应力、变形和周围环境影响等更加复杂。以江西省九江市某调蓄池及就地处理站基坑为工程背景,采用数值模拟的方法研究了相邻深基坑不同开挖方式的影响,并从土体变形、围护结构内力与变形、周边环境影响等角度对比相邻基坑同步开挖与分步开挖方案的差异及变化规律。研究结果表明:(1)同步开挖对坑间地表的沉降更为不利,若采用分步开挖,沉降可减小18%左右;(2)在不同开挖方式下,围护结构的最大水平位移相近,围护桩的整体弯矩差异不大;(3)对于既有管道的沉降,分步开挖更为不利,最大沉降发生在单个基坑开挖完毕后,若采用同步开挖,管道沉降可减小28.6%左右。(4)对于建筑物的沉降,同步开挖情形下,最大沉降发生于靠近调蓄池侧;分步开挖下,最大沉降发生于靠近就地处理站侧。In the construction of urban underground projects,especially in the central urban area,the adjacent foundation excavation projects are often encountered due to the restriction of land and construction schedule.Compared with the independent foundation deep excavation projects,the interaction of adjacent foundation excavations has an impact on the deformation of the supporting structures and the deformation of the surrounding soils.These factors will make the stress,deformation of the supporting structure and the impact of the surrounding environment more complex.The interaction between the foundation excavations cannot be ignored.This paper presents the foundation excavation of a storage tank and local treatment station in Jiujiang City,Jiangxi Province as the case history.This paper uses the numerical simulation method to study the influence of different excavation methods of the adjacent deep excavation and compares the difference and change pattern of the synchronous excavation and step-by-step excavation of the adjacent excavation from the perspectives of the soil deformation,internal force and deformation of the supporting structure,and the influence of the surrounding environment.It provides a reference for the relevant projects.The results show that:1)the synchronous excavation has more disadvantageous in terms of the surface settlement between the adjacent excavations.The surface settlement can be reduced by about 18%if the step-by-step excavation is adopted;2)Under different excavation methods,the maximum horizontal displacement of the supporting structure is similar,and the overall bending moment of the soldier pile is not different;3)From the settlement of the existing pipelines,the step-by-step excavation is more unfavorable.The maximum settlement occurs after the excavation of a single deep excavation.If the synchronous excavation method is adopted,the pipeline settlement can be reduced by about 28.6%.4)For the settlement of buildings,in the case of the synchronous excavation,the maximum settlement oc

关 键 词：相邻基坑 围护结构 同步开挖 环境影响分析 数值模拟 

分 类 号：TU473[建筑科学—结构工程]