Bivariate distribution of shear strength parameters using copulas and its impact on geotechnical system reliability
نویسندگان
چکیده
The objective of this paper is to investigate the effect of copulas for constructing the bivariate distribution of shear strength parameters on system reliability of geotechnical structures. First, the bivariate distribution of shear strength parameters is constructed using copulas. Second, the implementation procedure of system reliability analysis using direct Monte Carlo simulation (MCS) is developed. Finally, the system reliability of a retaining wall and a rock wedge slope is presented to explore the effect of copula selection on geotechnical system reliability. The results indicate that the system reliability of geotechnical structures under incomplete probability information could not be determined uniquely because the bivariate distribution of cohesion and friction angle with given marginal distributions and correlation coefficient could not be determined uniquely. The copulas for modeling dependence structure between cohesion and friction angle have a significant influence on the system reliability of geotechnical structures. Such an influence includes two phases separately. The first phase is that the dependence structure between shear strength parameters characterized by copulas affects the reliability of single failure mode, depending on the marginal distributions, dependence structure between shear strength parameters, and reliability level of each failure mode. The second phase is that the reliability of each failure mode influences on system reliability, only depending on reliability level of each failure mode and correlations among various failure modes. It is important to distinguish between the effect of copula selection on reliability of each failure mode and that on geotechnical system reliability. 2015 Elsevier Ltd. All rights reserved.
منابع مشابه
Updating Uncertainties in Soil Shear Strength Parameters with Multivariate In-Situ and Laboratory Test Data
In recent years, geotechnical engineers have paid much attention on reliability-based design. The probability density functions (PDFs) of the uncertain soil parameters are required for the reliability-based design. Once these PDFs are obtained, reliability analysis can be conducted, and reliability-based design can be achieved. Among the soil parameters, soil strengths play important roles in g...
متن کاملStress-Strength and Ageing Intensity Analysis via a New Bivariate Negative Gompertz-Makeham Model
In Demography and modelling mortality (or failure) data the univariate Makeham-Gompertz is well-known for its extension of exponential distribution. Here, a bivariate class of Gompertz--Makeham distribution is constructed based on random number of extremal events. Some reliability properties such as ageing intensity, stress-strength based on competing risks are given. Also dependence properties...
متن کاملNeural Networks for Assessing Shear Strength of Soils
Over the last few years or so, the use of artificial neural networks (ANNs) has increased in many areas of engineering. In particular, ANNs have been applied to many geotechnical engineering problems such as to predict pile capacity, settlement, liquefaction etc. The correlations between shear strength parameters and other soil properties individually are common among Geotechnical engineers. Bu...
متن کاملEffects of Glass Fiber Reinforced Polymer on Geotechnical Properties of Clayey Soil
Soil reinforcement can be considered as the combination of two parts. One part is soil for compressive stress capacity and another part is some material such as geosynthetics such as steel belts and fibers for tensile stress capacity. Soil improvement is one of the useful methods to increase the strength parameters of the soil. The main goal of this study is to evaluate the effects of GFRP on t...
متن کاملSystem reliability-based geotechnical design of braced excavations in soft clays
This paper presents a preliminary study on the system reliability for the geotechnical design of braced excavations in soft clays. In this system reliability geotechnical analysis, both ultimate limit state (ULS) and serviceability limit state (SLS) are considered. Herein, the ULS failure refers to the basal heave failure, while the SLS failure refers to failures sue to excessive ground-surface...
متن کامل