Iran University of Science and Technology

About: Iran University of Science and Technology is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Nonlinear system & Finite element method. The organization has 12917 authors who have published 24965 publications receiving 372013 citations. The organization is also known as: Governmental Technical Institute & Advanced Art College.

Brittle fracture evaluation of a fine grain cement mortar in combined tensile-shear deformation

Abstract: Different laboratory experiments are usually conducted to characterize the fracture behaviour and integrity properties of newly developed structural materials. However, the reported fracture tests data for an improved high strength cement mortar (HSCM) under combined tension-shear loading are not in agreement with theoretical predictions obtained from well-known fracture criteria. It is shown in this paper that the significant difference existing between the experimental and theoretical results is due to ignoring the effect of T-stress on the processes of crack growth in the HSCM test specimens. A modified fracture model is then used to show that the theoretical predictions can be corroborated by the experimental results when the effect of T-stress is taken into account.

Performance-based multi-objective optimization of large steel structures

Abstract: In recent years, the importance of economical considerations in the field of structures has motivated many researchers to propose new methods for minimizing the initial and life cycle cost of the structures subjected to seismic loading. In this paper, a new framework is presented to solve the performance-based multi-objective optimization problem considering the initial and life cycle cost of large structures. In order to solve this problem, a non-dominated sorting genetic algorithm (NSGA-II) using differential evolution operators is employed to solve the optimization problem, while a specific meta-model is utilized for reducing the number of fitness function evaluations. The required computational time for pushover analysis is decreased by a simple numerical method. The constraints of the optimization problem are based on the FEMA codes. The presented results for application of the proposed framework demonstrate its capability in solving the present complex multi-objective optimization problem.