Ramifications of blind adoption of load and resistance factors in building codes: reliability-based assessment

, Article Bulletin of Earthquake Engineering ; Volume 19, Issue 2 , 2021 , Pages 963-986 ; 1570761X (ISSN) Mahmoudkalayeh, S ; Mahsuli, M ; Sharif University of Technology

Springer Science and Business Media B.V 2021

Abstract

This paper presents a probabilistic approach to reveal the negative consequences of overlooking code calibration when adopting the provisions of nonindigenous building codes in design. A taxonomy of the national building codes of various countries whose provisions are adopted from one or more original standards is first presented. Next, the reliability-based approach to quantify the lack of safety that may arise due to the absence of code calibration is presented. This approach is then applied to the case study of the National Building Code of Iran, whose load and resistance factors are directly adopted from ASCE/SEI 7. To this end, seven steel building archetypes with various structural...

Studying the Problem of Maximum Matching in Stochastic Environments

, M.Sc. Thesis Sharif University of Technology Soheil, Farehe (Author) ; Ghodsi, Mohammad (Supervisor)

Abstract

The problem studied in this research is the online stochastic bipartite matching. In this problem the vertices of one side of the given graph arrive in an online manner, with respect to a probability distribution. Also the edges of the graph exist according to a given probability distribution and one should perform queries from an oracle to know about the existence of an edge. The given graph shall be weighted or unweighted. The goal here is to find a maximum matching in the graph that is as close to the omniscient optimum as possible, while the number of queries performed per vertex is limited. In the general case of the problem, there are no specific conditions, but in other versions,...

Reliability-based Evaluation and Calibration of Load Combinations for the Design of Steel Building Structures of Iran

, M.Sc. Thesis Sharif University of Technology Mahmoudkalayeh, Soheil (Author) ; Mahsuli, Mojtaba (Supervisor) ; Ghasemi, Hooman ($item.subfieldsMap.e)

Abstract

The objective of this thesis is to evaluate and calibrate design load combinations of steel building structures of Iran based on the reliability theory. The importance of this research stems from recognition that the design load combinations for steel structures in Section 6 of the National Building Code of Iran have been completely adopted from the ASCE/SEI 7-10 standard, whereas the factors that affect these load combinations differ in Iran from those of the United States. Examples are the difference in the construction industry economy, lower quality of here and the differences in probability distributions for the specifications of steel. Hence, the load combinations need to be calibrated...

Modelling of Frictional Cracks by the Extended Finite Element Method Considering the Effect of Singularity

, M.Sc. Thesis Sharif University of Technology Saeed Monir, Saeed (Author) ; Khonsari, Vahid (Supervisor) ; Mohammadi, Soheil (Co-Advisor)

Abstract

When a crack is subjected to a compression field, it will close and its edges will get into contact with each other. Depending on the direction and magnitude of the loads and also the coefficient of friction, ‘stick’ or ‘slip’ situationsbetween the edges will occur. This type of crack is known as ‘frictional crack.’ In this project, first these cracks are studied analytically and the order of singularity is derived using asymptotic analysis and also the analytical fields are determined for both ‘isotropic’ and ‘orthotropic’ materials. Then, numerical simulations are carried out using extended finite element method which is considered as the most powerful means for analyzing the problems...

Theoretical and Numerical Analysis of Shock Waves Propagation in Porous Medium

, Ph.D. Dissertation Sharif University of Technology Nemati Hayati, Ali (Author) ; Ahmadi, Mohammad Mehdi (Supervisor) ; Mohammadi, Soheil ($item.subfieldsMap.e)

Abstract

Particulate porous mateials have always been of interest in terms of reducing shock waves effects in different protective applications. Therefore, the physics governing the flow in porous media is especially significant for which different models have been presented by the researchers. The complexities of these media have caused many existing models to be unable to properly predict the behavior of granular media under shock loadings. On the other hand, the complexity of the equations makes the numerical solution of them cumbersome and costly in a way that many researchers do not solve the whole coupled equations and reduce their number. In addition, current high-resolution TVD solutions of...