天津高新技术产业园区海泰小区路面塌陷成因

路面坍陷是威胁城市安全运行的重要隐患。天津高新技术园区海泰区段路面塌陷、地下暗穴空洞和污水管渗漏三者之间,存在着密切的联系。作者通过现场勘查、地质雷达探测、管线机器人内窥探视技术、工程钻探、三维地质建模等综合方法研究其塌陷成因机理。研究表明,其成因机理在沿海地区具有代表性和典型性,即脆弱的自然(地质)系统与人工(工程)系统在多种因素复合控制下的相互作用,管线埋设于软土层中,由于自然沉降和后期压实作用,导致软土层垂向和侧向差异迁移,引起拼接而成的污水管线在接触部位产生缝隙、破损,使高于管线的地下水向管内渗漏,土层因颗粒物质流失而形成空洞,进而导致路面塌陷。据此,提出管线埋设前和塌陷后所采取的治理措施,重点在于防止因管线破损而造成地下水和管线内的排泄水产生交换,避免管线外转的土层颗粒流失。

IN-SITU INVESTIGATION ON CAUSES OF ROAD SURFACE SINKING AT HAITAI DISTRICT OF TIANJIN HI-TECH INDUSTRIAL PARK

Road surface sinking is a serious hidden risk for safety travelling in city. There is a close relation among road surface sinking, underground cave and sewage pipe linkage in Haitai District of Tianjin Hi-tech Industrial Park. In this paper, a generation mechanism of road surface sinking is studied through site investigation, geological radar detection, pipeline robot endoscopic detection technology, engineering drilling and 3-dimensional geological modeling. Through study, it is proven that the generation mechanism is representative and typical in coastal area. The weak nature(geological) system interacts with artificial(engineering) system under complex control of multiple factors. The pipeline is buried in safe soil. Its lateral and vertical immigration can occur due to natural settlement and compaction. It can cause crack and damage to sewage pipes at the joints, which further makes the underground water above the pipeline leaking into the pipeline. Then caves are formed due to loss of particles of soil. It finally leads to road surface sinking. Accordingly, treatment measures before burying pipeline and after occurrence of road surface sinking are proposed respectively. The focus is to prevent exchange of underground water and sewage water in the pipeline due to damage of pipeline and to avoid loss of soil particles surrounding the pipeline.