特高拱坝基础破坏、加固与稳定关键问题研究

KEY PROBLEMS OF FOUNDATION FAILURE,REINFORCEMENT AND STABILITY FOR SUPERHIGH ARCH DAMS

特高拱坝的坝基条件大都比较复杂,基础岩体的破坏、加固与稳定评价出现一些关键新问题:坝基岩体力学参数合理取值;坝踵、坝趾基础开裂机制;坝肩非典型软弱蚀变带的处理;贴角区灌浆时机选择;坝趾锚固力损失评价以及大坝-基础非线性稳定分析等。传统的分析方法和加固处理措施日益受到挑战。结合实际工程,就如上问题涉及的研究方法、处理措施进行抛砖引玉的讨论和分析。针对这些新问题,无论数值模拟还是物理试验,都应该采用细宏观尺度的转变方法,并作为非线性方法的理论基础,进一步完善发展,以更好地指导实际工程的优化设计和建设。

Superhigh arch dams generally locate in complicated foundation.The failure,reinforcement and stability mechanism of foundation are facing with challenging original problems,such as：mechanical parameter and strength reasonable selection of jointed rocks;cracking problem in the heel and toe of dams;reinforcement measures for atypical faults and altered rock;grouting timing design for toe area of dam;anchorage force damage and nonlinear evaluation for integrity stability.In this paper,these key problems involved in the research methods,and reinforcing measures to carry on the discussion and analysis based on practical engineering.The micro-macro transfer method is proposed for coupling nonlinear analysis method.By employing this method,numerical simulation and experimental investigation on foundation failure,reinforcement and stability evaluation of superhigh arch dam need to further carry out for servicing dam design and construction.