重力坝抗滑稳定可靠度分析:(一)相对安全率方法  

Reliability analysis on sliding stability of gravity dams: Part Ⅰ,an approach using criterion of safety margin ratio

作　　者：陈祖煜[1,2] 徐佳成[1] 孙平[1] 吴超[1] 王玉杰[1,2] 陈立宏[3] 

机构地区：[1]中国水利水电科学研究院岩土工程研究所,北京100048 [2]流域水循环模拟与调控国家重点实验室,北京100038 [3]北京交通大学土木建筑工程学院,北京100044

出　　处：《水力发电学报》2012年第3期148-159,共12页Journal of Hydroelectric Engineering

基　　金：水利部公益性行业科研专项经费项目(200801005);国家自然科学青年基金(50909002)

摘　　要：随着可靠度理论在结构和岩土工程领域日益得到广泛的应用,诸如强度指标变异系数的取值、评判标准的合理性及与确定性模型计算结果的相关关系等问题亟待解决。本文提出可靠度方法相对安全率ηR的概念和计算公式,以无重介质地基的极限承载力为例在数学上严格证明了传统方法与可靠度方法相对安全率的等价性。并以单滑面重力坝算例及8个典型重力坝深层抗滑工程实例对基于可靠度设计方法相对安全率ηR和单一安全系数方法相对安全率ηF、分项系数设计方法相对安全率ηP的可比性和相关性作了验证,证实了可靠度方法相对安全率ηR作为描述建筑物失效概率相对允许值裕幅的指标的合理性,并以ηP=ηR为判据进行了分项系数标定的工作。同时,对典型工程案例向家坝重力坝深层抗滑做了相对安全率的计算,揭示了这一新方法在生产实践中应用的可能性。Extensive application of probabilistic theory in structural and geotechnical engineering requires solutions to a series of issues such as determination of the coefficients of strength parameter variations,establishment of safety criteria and evaluation of the analytical results with deterministic models.This paper proposes a new concept called ＂ratio of safety margin＂ ηR and its calculation method,and demonstrates the equivalence of the ratio of safety margin calculated by the reliability analysis and its corresponding ηF obtained by the traditional method through testing bearing capacity of weightless soils.An extensive assessment based on a testing concrete dam and eight grade-I projects has shown that the calculated values o f ηR and ηF are comparable and correlative,and it verifies that the new concept is useful and applicable to evaluation of structural safety.This paper also presents some calibration results of the relationship ηP=ηR for partial factors and a case study of Xiangjiaba concrete dam,showing application potential of safety margin ratios to practical projects.

关 键 词：水工结构 抗滑稳定 可靠度分析 混凝土重力坝 相对安全率 

分 类 号：TV31[水利工程—水工结构工程]