Calculation Model of Equivalent Strength for Induced Crack Based on Double-K Fracture Theory and Its Optimizing Setting in RCC Arch Dam
Calculation Model of Equivalent Strength for Induced Crack Based on Double-K Fracture Theory and Its Optimizing Setting in RCC Arch Dam
复制标题
DOI：
--
复制
发表时间：
2005
期刊：
影响因子：
--
通讯作者：
张小刚;宋玉普;吴智敏
中科院分区：
文献类型：
--
作者：
张小刚;宋玉普;吴智敏
通过对碾压混凝土三点弯曲梁两种不同试件尺寸的断裂试验，得到了碾压混凝土三点弯曲梁的P-CMOD完全曲线。应用双k断裂理论，对KiniⅠC、KunⅠC以及临界有效裂纹长度和临界裂纹尖端张开位移进行了计算。基于上述双k断裂参数，建立了诱导裂纹等效强度计算模型，从而确定了诱导裂纹起裂、稳定扩展和不稳定断裂的计算方法。此外，对沙排拱坝应力场的有限元模拟分析和不同海拔高度现场观测的诱发裂缝展开点验证了该模型的可靠性。最后，对碾压混凝土拱坝诱导裂缝的最佳设置进行了研究。提高了碾压混凝土拱坝诱导裂缝的设计水平，满足了工程实践的需要。
By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer's optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice.