High rock-fill dam membrane anti-seepage body on deep coverage layer and construction method of high rock-fill dam membrane anti-seepage body

The invention discloses a high rock-fill dam membrane anti-seepage body on a deep coverage layer and a construction method of the high rock-fill dam membrane anti-seepage body. The membrane anti-seepage body is composed of a concrete protection layer, a geomembrane anti-seepage layer, a flexibility cushion layer and a transition layer. The concrete protection layer is a cast-in-place fiber concrete layer for a reserved cross joint and a vertical joint and located on a surface layer to protect a geomembrane. The geomembrane anti-seepage layer is a two-cloth and one-membrane composite geomembrane and is located in the middle to play a role of preventing seepage. The flexibility cushion layer is a polyurethane pervious concrete layer and located at the bottom of the anti-seepage body to support the geomembrane and to transmit and disperse water loads. The rough granule transition layer is arranged between the flexibility cushion layer and a rock-fill dam body. The construction method comprises the technical steps of filling and building the transition layer, pouring the flexibility cushion layer, paving the composite geomembrane, pouring the concrete protection layer and the like. The membrane anti-seepage body can keep stable on a high rock-fill dam slope, the ability of adapting to deformation of a coverage layer dam foundation and the dam body is high, the structural form is simple, construction is fast, and the anti-seepage problem of the high rock-fill dam on the deep coverage layer can be effectively solved.