Experimental study on drainage characteristics of new composite drainage pipes in tailings pond

The clogging of the drainage facilities in a tailings pond is a common phenomenon, and is also an important factor affecting its safety. In order to improve the drainage capacity and anti-clogging performance of the drainage pipes, new composite drainage pipes are proposed. A layer of lattice net is added between the geotextile and the perforated pipes in the new composite drainage pipes. The indoor model tests are carried out to study the influences of different lattice net structures and opening ratios of the perforated pipes on the drainage characteristics of the new composite drainage pipes. The anti-clogging performance of the new composite drainage pipes is analyzed, and their drainage mechanism is revealed. The results show that the drainage capacity of the composite drainage pipes increases because of larger equivalent opening area and optimized drainage path. With the increase of the opening rate of the perforated pipes, the influences of the lattice net on the drainage capacity of the drainage pipes become smaller. The outsourced lattice network improves the anti-clogging ability of the drainage pipes. With the clogging of geotextiles, the drainage capacities of the ordinary drainage pipes wrapped only with geotextiles and the new composite drainage pipes both decrease, and the reduction of the drainage capacity of the ordinary drainage pipes is more serious. When the connection direction of unidirectional connected lattice net is at an angle with the longitudinal direction of drainage pipes, the drainage capacity of the drainage pipes does not increase but decreases. When using the unidirectional connected lattice net, it is necessary to ensure that the connection direction of the lattice net is consistent with the longitudinal direction of the drainage pipes.