为了确保高重力坝的稳定安全,针对高重力坝坝基存在抗剪强度与正应力呈非线性关系的特点,重点研究了二次抛物线形的抗剪强度包络线。在此基础上,建立了基于二次抛物线形抗剪强度包络线的功能函数。结合改进的JC法,提出了高坝坝基失稳可靠度的计算方法,并开发了相应的程序。将上述基本原理和方法应用于某高坝工程除险加固后的稳定安全度校核,分析结果表明该坝经过除险加固处理后坝体具备一定的稳定安全储备能力。
In order to ensure the stability and safety of high gravity dams,the shear strength envelope curve in the shape of quadratic parabola was studied with regard to the nonlinear relationship between the shear strength and the normal stress for high dam foundations.On such a basis,a performance function based on the shear strength envelope curve in the shape of quadratic parabola was established.Combined with the improved JC method,a method for calculating the reliability of dam foundation failure was proposed,and the corresponding program was developed.The above basic principles and methods were applied to the calibration of safety degree for the stability of a high dam after rehabilitation.The results indicate that the dam has certain reserved capacity of stability safety after rehabilitation.