本文通过７个小尺寸和１个大尺寸的钢筋混凝土断面模型试验，研究重力坝深（底）孔在坝体自重和内水压力以及超内水压力作用下的结构特性和破坏规律．重点探讨混凝土和钢筋应力应变、混凝土开裂、裂缝宽度和裂缝扩展规律，为建立更为科学的孔口配筋理论提供依据 In this paper, the structural characteristics and failure rules of deep and bottom holes in gravity dam under the action of dam self-weight and internal water pressure and super-internal water pressure are studied through seven small and one large-section reinforced concrete cross-section model tests. Focus on stress and strain of concrete and steel, concrete cracking, crack width and crack propagation law, to provide a more scientific basis for the theory of reinforcement of the orifice