论混凝土坝技术的几个重要问题

目前我国正在兴建的混凝土坝的高度、数量、坝模均居世界第一位。本文就混凝土坝技术的几个重要问题进行讨论，《混凝土重力坝设计规范》DL5108-1999放弃过去长期采用的基于90d龄期的混凝土标号R，改用基于28d龄期的混凝土强度等级C，由于水坝施工期长达数年。这一改变是不合适的，抗压安全系数是拱坝设计的重要指标，目前国内已建和在建的200m以上特高拱坝的抗压安全系数均低于200m以下的一般拱坝，这是不合理的，应予以改变，混凝土坝设计过去一直采用安全系数法，文献[1]改用基于可靠度理论的多项系数法，由于样本太少，用可靠度理论进行混凝土坝设计欠妥，仍应采用安全系数法。

On Some Important Problems in Concrete Dam Techniques

The concrete mark beased on 90d or 180d age of concrete is more appropriate for concrete dams than the concrete strength class based on 28d age of concrete.At present,the confficient of safety for very high concrete arch dams are too low, it is suggested that the coefficients of safety on compressive stresses in very high concrete arch dams not be less than those for common arch dams.Because the original data is not sufficient, the design method based on the theory of reliability is not suitable for concrete dams.