Parametric Evaluation of the Y- Shaped Bracing Frame and Introducing a New Method for Design

, M.Sc. Thesis Sharif University of Technology Sedaghati, Parshan (Author) ; Mofid, Masoud (Supervisor)

Abstract

This paper investigates the behavior of the Y-shaped bracing system. Because of the special type of eccentricity in this system, the behavior of the frame is strongly dependent on the geometrical changes of the braces. So that even in the elastic region, it shows the geometrically nonlinear behavior. The amount of eccentricity is very effective on the nonlinear behavior of the frame. Also the ratio of cross sections of the bracing members has a very important impact on the expected performance of the frame. The results show that this system tolerates large displacements, and can act like a base isolation system. Firstly, using a two-dimensional accurate modeling related to the geometrical...

Design and Fabricate Force Plate Device to Gathering and Processing Data for Automatic Detection of Lameness in Ruminants

, M.Sc. Thesis Sharif University of Technology Sedaghati, Nasser (Author) ; Akbari, Javad (Supervisor)

Abstract

Lameness in dairy cattle is a crucial welfare issue after infertility and mastitis in dairy industry, and over the years scientists are attempting to present a detection method. In recent it is attracting more attention to make the identification and discrimination of sounds and lames systematic and automatic. Right now, the most hopeful results have been obtained through the measurement of Ground Reaction Forces (GRF) of hooves, and analysis of load distribution between four legs, which seems applicable for wide use in dairy industry.However, the accuracy, validity, and reliability of discrimination is still far from an acceptable point, that is because of a great lack in understanding...

Studying Processability, Mechanical and Rheological Properties of Cross-Linked EVA Through Vitrimerization Reaction

, M.Sc. Thesis Sharif University of Technology Sedaghati, Amin (Author) ; Pircheraghi, Gholamreza (Supervisor)

Abstract

Polymers are divided into two categories: thermoset and thermoplastic. Thermoset polymers cannot be reprocessed and deformed due to their network structure and permanent and rigid crosslinking connections. Vitrimer materials that have been proposed in recent years; In addition to maintaining their network properties at low temperatures, they have the ability to change shape and reprocess at high temperatures. Therefore, the production of Vitrimer materials can be a suitable solution to reduce the amount of plastic waste produced. These materials consist of a dynamic covalent network in which vitrimerization reactions are performed between different functional groups. The basic polymer used...

Parametric study and design approach of off-center bracing systems

, Article Structural Design of Tall and Special Buildings ; Volume 26, Issue 3 , 2017 ; 15417794 (ISSN) Sedaghati, P ; Lotfollahi, M ; Mofid, M ; Sharif University of Technology

2017

Abstract

This paper presents an effective approach for the seismic design of off-center bracing systems (OBSs). The nonlinear behavior of an OBS can be specified by evaluation of two yielding stages representing tensile yielding of different bracings. This can be achieved when stiffness of the corner brace member is deliberately considered less enough to act as a fuse-like component. An accurate two-dimensional finite element modeling for the geometric and material nonlinearity of such systems considering buckling behavior of the brace members is developed. Through an extensive parametric study, the optimal ratios of the influential parameters of OBS are obtained, and their effects on the nonlinear...