Composite Geomembrane In Seepage Control Engineering Application Of City Rivers And Lakes

The Yong ding river is the largest branch of Haihe River. The part inBeijing area is170km in length and about3200km2in water shedarea. Becauseof the long-term dry state of the basin, it is unable for the natural inflow to formthe effective runoff so that many small pits have been formed with very steepslope walls.Plants cannot grow up in the river banks and the riverbed has beengradually becoming sandy.The ecological environment of Yongding River isdeteriorating year by year with the pollution of sewage discharged bringing bysandstorm in winter and spring seasons. With the development of socialeconomy, people need an improving water environment. In order to create abeautiful water environment, the government test ablished the "Yongding Rivercorridor green building plan".The project in this paper belongs to the secondbatches of the implementation of the plan, executing in2011-2013to create agood environment and condition for the2013Ninth China (Beijing)International GardenExposition.In order to forming a lake land scape by use of renewable water sources,some measures need to be taken to solve seepage problem due to the directcontact of river water and soil stratum. In this paper, research theories aboutwater infiltration and anti-seepage technologies are firstly summarized, andcomposite geomembrane is chosen as a preliminary technique according to itsadvantageous characteristics. Secondly, the thickness of compositegeomembrane is calculated based on the classical theory method and the naturalgeological conditions of the engineering. A series of experiment is taken todetermine the material parameters and then the foundation treatment andanti-seepage scheme is designed. During the project operating, the seepagequantity has been monitoring. By comparing the actual monitoring results withthat from theoretical calculation, it is shown that the designed anti-seepagesystem has achieved a good effect. Finally some suggestions about the lakewater resource scheduling are put forward and valuable experiences aresummarized for guidance to the water resource management of urban rivers orlakes.