某RCC拱坝诱导缝分缝形式及效果分析

Study on Setting Schemes and Effects of Induced Joints of A Certain RCC Arch Dam

RCC拱坝设置诱导缝是解决施工期温度裂缝的有效措施,由于拱坝结构受力复杂,各个工程差异大,诱导缝位置和数量等对设缝效果、拱坝安全有明显影响。为此,以某RCC拱坝为例,根据初拟的5个设缝方案建立了精细有限元网格模型,并进行了全过程、全坝段的温度场和应力应变场仿真模拟计算,研究了诱导缝位置、数量对坝体变形、应力分布与抗裂安全性的影响。结果表明,设置诱导缝后,坝体最大拉应力分布范围减小、幅值明显降低,拱坝整体刚度也有所削弱;施工期坝体的拉应力状态随设缝数量增加有明显改善,但设缝数量对拱坝整体刚度影响不显著,按方案5设缝后,拱坝的拉应力水平及分布满足设计规范要求。

Induced joints are used to solve temperature cracks during construction period in roller compacted concrete arch dams. Due to complex force of arch dam structure and difference of each project, its location, quantity and setting schemes are very important to the safety of the arch dam. In this paper, a fine finite element mesh model of an RCC arch dam was established, and five joint schemes were set up to simulate the temperature field, stress and strain field in the whole process. The impact of the position and quantity of induced joints on the deformation, stress distribution and anti-cracking safety of the dam body was studied. The results show that after setting the induced joints, the range and peak value of the maximum tension stress of the dam body are obviously reduced, but the overall stiffness of the arch dam is also reduced. The state of the dam tensile stress during construction period is improved with the setting of number of joints. However, it does not obviously affect the overall stiffness of the arch dam. Finally, scheme five is recommended as the best scheme.