Study On The Technology And Its Demonstration For The Construction Of Sewage Interception In Suzhou Urban District

Constructing and completing sewage system is an effective and ultimate means to control water environment pollution in urban area. Suzhou is an ancient city possessing 2500 years history, in which the drainage system is complicated, and residential area concentrate with vast numbers protected buildings. The construction of sewage interception faced some difficulties, such as construction area vast, room for pipeline setting narrow, and less experience for reference. Therefore, the related technologies for the construction of sewage interception were studied, it is expected which could be as the instruction for conducting the project.For pipeline setting in narrow room area, the grouting method could be used to protected the adjacent building, and side wells could be conducted for the discharge of sewage with the advantage of easy constructing and less investment. Pipe jacking method could be used to solve the difficulties setting pipeline in bumper-to-bumper traffic area. In public toilets and food market area, grids were obligatory to avoid pipe clogging.In order to decrease conduit slope, UPVC drainage pipeline was used, with adopting reasonable avoidance of pipeline measures. These measures guaranteed the smooth implementation of the project and brought the convenience of the future use and maintenance.Moreover, the thesis analyzed the effectiveness and studied the technical measures in transforming combined pipes to rain water pipes. The study results showed that this kind of rain water pipes could effectively collect and drain ground rainfall due to common drizzle, moderate rain, heavy rain, even rainstorms triggered by typhoon in normal years. That combined pipes were transformed to rain water pipes benefited us a lot,such as acquiring big economic benefits due to saving a lot of project investment, bringing convenience to the masses owing to reducing excavation, effectively utilizing underground space, and the reducing destruction of trees and impact on other pipelines.During the construction of sewage interception, the related river water quality was monitored, which revealed that increasing wastewater-collection ratio could improve water quality distinctly, with water pollution composite index decreased 18%～53%. The study indicated that separate system for sewage and rain water...