本文提出了全级配混凝土试件单轴拉、压应力作用下高压水劈裂模拟试验新方法,并运用断裂力学对试验结果进行了分析和参数校核,推导了判定重力坝坝踵是否会发生水力劈裂的分析公式。基于试验、计算分析和国内外高重力坝比较研究,初步给出了评估特高混凝土重力坝是否可能发生高压水劈裂的断裂力学条件,经比较可初步用于评判重力坝抗高压水劈裂能力。基于工程比较研究,提出了200m以上特高重力坝,设计准则中需要考虑高压水劈裂的影响。当前国内外采用的重力坝设计准则,对特高重力坝,尤其是碾压混凝土重力坝,都有可能出现偏于不安全的情况。
A new lab simulation method for concrete structure hydraulic fracturing test has been presented under tensile stress or compressive stress condition. Fracture mechanics has been used to verify the lab re- sult and calculation parameters used. Based on the results of the experiment, FEM analysis and compara- tive studies between super high gravity dams in China and other countries, estimated formula for hydraulic fracturing analysis on concrete structure and gravity dams were developed. It can be used to evaluate the safety of super high gravity dam considering hydraulic fracturing. Based on the results achieved, it may have safety problem for gravity dams over 200m designed by current specifications of China, USA or Swit- zerland, especially for RCC gravity dams, and therefore it is necessary to consider the hydraulic fracturing in the specification of gravity dams over 200m.