碾压混凝土拱坝诱导缝断裂特性研究

通过数值计算分析了诱导缝的断裂特性;以实际工程为例,用断裂力学方法模拟了诱导缝的开裂过程,并对诱导缝的作用进行了探讨.结果表明:诱导缝开裂特性与诱导缝的位置、形式、两侧约束距离及相邻缝端的影响等因素有关;在诱导缝的开裂过程中,坝体应力有所降低,特别是诱导缝完全开裂时,应力下降非常明显;诱导缝设置可以首次开裂条件作为判别依据;为减少施工工序、提高施工效率,可在保证始终满足诱导缝开裂判别式的前提下适当加大中部诱导板的缝间距.

Study on fracture behaviors of induced joints in RCC arch dams

The fracture behaviors of induced joints were analyzed by numerical calculation at first.Then,with a practical project taken as an example,the cracking course of induced joints was simulated by use of the method of fracture mechanics,and the function of induced joints was discussed as well.Some conclusions are drawn: the opening of induced joints depends on such factors as their position,type,distance to the constraints at two sides of the joints,and adjacent crack tip;the stress of the dam body gradually decreases in the cracking course of induced joints,and the stress decreases sharply when induced joints are cracked thoroughly.As a conclusion,the condition for the first opening of induced joints could be taken as a criterion for their setting;thus it could be ensured that the first opening of induced joints occurs before the cracking of other parts of the arch dam.To simplify the working procedure and improve the construction efficiency,the distance between induced plates in the middle section of the dam body could be enlarged properly under the condition that opening criterion of induced joints is satisfied.