堆石坝面板收缩性贯穿裂缝的理论分析及防裂措施

堆石坝面板的裂缝主要源于因温降和干缩引起的收缩。当面板的收缩变形受到约束后会产生拉应力而导致裂缝。本文推导了面板收缩后受堆石体及侧面先浇块约束时沿断面拉应力分布的解析解，求出最大拉应力断面位置及应力值与底面及侧面约束的关系。数值结果表明，面板与堆石体之间的凝聚力及先浇块的侧面约束是引起裂缝的重要因素。根据本文的理论分析提出了无贯穿性收缩裂缝的设计准则及相应的工程措施。

Theoretical analysis of through shrinkage cracks in the face slabs of CFRD and the preventive measures

Through shrinkage cracks in the face slab of CFRD are mainly caused by temperature drop and drying shrinkage. Restrained deformation of face slab will usually result in tensile stress through the thickness of the slab and cause cracks. An analytical solution of the distribution of shrinkage tensile stress in the face slab restricted by the cushion and lateral slabs is derived. The position of maximum tensile stress and its relation with restraints from the cushion and the lateral slabs are determined. It is shown that the cohesion between face slab and cushion and the restraint of lateral slabs plays a key role in the formation of cracks. No-through shrinkage crack design criteria, together with corresponding engineering practices are also recommended according to the theoretical analysis.