Research on Anti-seepage Measures of Qiantang River Geotextile Tube Cofferdam Based on Composite Geotextile Tubes
The geotextile tubes cofferdam is a structure stacked layer by layer of geotextile tubes,and there are joints between the layers and between the bags,which can cause serious seepage and hinder the dry construction in the weir.Based on the seepage contribution of each part of the geotextile tube cofferdam from the previous research,a new method of composite geotextile tube method was proposed,and the seepage model test of conventional geotextile tube and composite geotextile tube under overlying pressure was carried out to obtain the empirical formula of overlying pressure-permeability coefficient.Then the numerical model of test scale and field scale was established.The above empirical formula was input into the model to calculate the seepage flow,which further clarified the effectiveness of the anti-seepage measures of composite geotextile tube.It is found that compared with the conventional geotextile tube,the staggered end to end lap joint of the composite geotextile tube can significantly reduce the seepage rate of the geotextile tube cofferdam,and the permeability coefficient is only 10%of the conventional geotextile tube when the overlying load is 15 kPa.At the field scale,the seepage flow rate of each section of the cofferdam(200 m)after using the composite geotextile tube is 0.5 m3 per hour,which is reduced by over 90%than that of the conventional geotextile tube.
composite geotextile tubegeotextile tube gapseepage between tubesanti-seepage measures
万方数据
维普
