Dam body structure design method for reducing stress of anti-seepage wall of upper core wall earth and rockfill dam of deep and thick covering layer

The invention provides a dam body structure design method for reducing the stress of a diaphragm wall of a core wall earth and rockfill dam on a deep covering layer, and belongs to the technical field of core wall earth and rockfill dam engineering. According to the method, dam body structures of areas on the two sides of the top of an existing covering layer upper core wall earth and rockfill dam diaphragm wall are improved. The specific method comprises the steps that soft belts are arranged on the upstream side and the downstream side of the top (the lower portion of a core wall) of the diaphragm wall respectively, strip-shaped high-plasticity soil is selected for the soft belts, the inner sides (the sides, close to the core wall, of the soft belts are cushion materials, the outer sides of the soft belts are filter materials, and loss of the high-plasticity soil in the seepage process is avoided. The soft belt can adapt to larger settlement difference between an anti-seepage system (a core wall and an anti