Loading...
Search for: mofid--massoud
0.009 seconds
Total 37 records

    Introduction of Concentric Braced Frame Equipped with BRB & YE (yielding element) and Quantification of Seismic Perfomance Factors
    Based on FEMA-P695

    , M.Sc. Thesis Sharif University of Technology Souri, Omid (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    This investigation is intended to assess the behavior of SCBFs in the presence of typical brace members, which buckles in compression, and BRBs joining by yielding elements. While braces play a role in providing stiffness for structure, central yielding elements will act as energy-absorbing fuses. In this frame type, energy dissipation will mainly be undertaken by BRBs and yielding elements. The mentioned yielding elements do this by initiating plastic hinges in each corner of the central frame. As it is clear, designing a structure that includes the stated lateral-load-resisting system necessitates seismic performance parameters to be evaluated. Hence, by pursuing the FEMA P695 methodology,... 

    Developing of MIDA Method in Irregular Structures in Plan with Concentrated Plasticity Model

    , M.Sc. Thesis Sharif University of Technology Yari, Mohammad Hossein (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    In this research, modal incremental dynamic analysis (MIDA) has been investigated on three-dimensional structures with irregular plans. The MIDA method is an incremental static analysis that considers higher modes of the structure. In fact, it is a combination of modal pushover (MPO) and incremental dynamic analysis (IDA) methods that incorporate the advantages of both and is much faster than the IDA method. Compared to constant analyses, incremental analysis is more extensive in terms of results and response to earthquakes. Due to the uncertainties in the nature of future earthquakes, engineers use the IDA method to achieve a broader view of the structure's response under potential... 

    Effect of Efficient Management on Reconstruction of Apartment Buildingsi n Region 1 of Tehran City Using Hierarchical Analytical Model

    , M.Sc. Thesis Sharif University of Technology Tahmasebi, Mohammad (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    Nowadays population growth, people housing demand and urbanization tendency has increased the land and house prices. So the constructers tend to build apartments. Time consuming and heavy costs of building and renovation has made the owners to rebuild the damages of their houses in case of an accident. Time and cost are the main factors in construction which includes rebuilding. Buildings and especially apartments renovation is expensive and prolonged. So the rebuilding tendency has been noted more than ever. In this study it has been tried to control costs and time by efficient management to save the rebuilding time and money. Two kinds of questionnaire has been applied to study different... 

    Geometrically Nonlinear Vibration of Concrete Funicular Shells Under Impulse Loads

    , M.Sc. Thesis Sharif University of Technology Daneshmand, Niloofar (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    Reinforced concrete shells are widely used to cover the small to large area with more aesthetics at minimum cost. Shell structures carry load through their shape rather than material strength. Funicular shells are special type of shells that their shape is obtained so that stresses be compressive under a special load (for shell, this load is its dead weight). This study deals with geometrically nonlinear vibration of funicular shells on a rectangular ground plan under impulse loads using nonlinear shallow shells theory. The boundary conditions are considered as clamped edges. Displacement components are product of position and time functions. The analysis is based on the expansion of... 

    Parametric Study on Seismic Performance of Spherical RC Domes

    , M.Sc. Thesis Sharif University of Technology Gholamrezaie, Amir (Author) ; Vafaei, Abolhassan (Supervisor) ; Mofid, Massoud (Co-Advisor)
    Abstract
    The present parametric study discusses the effective factors on seismic performance of spherical RC domes. For this perpose, a series of domes with different spans, a variety of contact angles (the angle between the bottom of the sphere and the center of the sphere), openings with different areas and various support condition are studied. Then the value of response modification factor and it's components is determined to take into account the effect of each component. The results obtained indicated that the response modification factor increases as the contact angle enhances. However, the span of domes insignificantly affects the value of response modification factor.also analysis on domes... 

    Dynamic Response of Concrete Funicular Shells under Impulse Loads

    , M.Sc. Thesis Sharif University of Technology Sabermahany, Hadi (Author) ; Vafai, Abolhassan (Supervisor) ; Mofid, Massoud (Co-Advisor)
    Abstract
    Reinforced concrete shells are widely used to cover the small to large area with more aesthetics at minimum cost. Shell structures carries load through their shape rather than material strength. Funicular shells are special type of shells that their shape is obtained so that stresses be compressive under a special load (for shell, this load is its dead weight). This study deals with forced vibration of funicular shells on a rectangular ground plan under impulse loads using shallow shells theory. Two boundary conditions, simply supported and clamped, are considered. Displacement components are product of position and time functions. The analysis is based on the expansion of displacement... 

    On the Characteristics of The Behavior of Multi-story Steel Frames Accompanied by Steel Shear Walls with Openings

    , M.Sc. Thesis Sharif University of Technology Rostami, Parisa (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    As steel shear walls are usually applied in the central cores of buildings (around the elevators and stairs), the use of opening as door is inevitable in steel shear wall spans. On the other hand, because of weakening the performance of steel shear walls due to the presence of these openings, it is necessary to apply stiffeners around it. The use of stiffeners around all sides of opening continued to beams and columns, is very expensive. Therefore, the necessity of studying on the effect of different arrangements of stiffeners on the behavior of steel shear walls is felt. In this research, a number of steel shear walls with different characteristics in terms of plate aspect ratio, location... 

    Analyzing and Modeling of Novel Semi- fixed Beam to Column Connections in Steel Structures

    , M.Sc. Thesis Sharif University of Technology Boroumandi, Babak (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    The flexibility of beam to column connections and its effect on behavior of steel structures is one of the most important problems, which is interesting to engineers and scientists for more than 80 years. Hence many studies conducted on this topic to clarify the behavior of this type of connection. In this work, it is tried to study the behavior of double plate connections, which are welded to the beam web by finite element modeling and mathematical method. A novelty of this thesis is some top trough plate which has been implemented to column under beam flange. Based on finding of this thesis few recommendation can be made related to usage of top trough plate. In brief reduction of... 

    Design, Modeling and Investigation of Seismic Behavior of Bracing Type Steel Shear Panels

    , Ph.D. Dissertation Sharif University of Technology Akbari Hamed, Arash (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    So far a number of solutions have been proposed to resolve some problems of steel plate shear walls including large induced loads on the surrounding members, late panel’s yielding along with lack of openings. One of the forms that can be considered for steel shear walls is braced shear panels.Regarding to the many advantages of this structural system, in this thesis steel shear panels with concentric or eccentric bracing have been introduced. For this purpose, first a procedure for plastic analysis and design, aiming to develop a predetermined collapse mechanism, is proposed. The results demonstrate that the closed-form analytical equations along with the extension of failure mode control... 

    Effects of Thickness and Compressive Strength on The Behavior of Corrugated Fiber-Reinforced Concrete Shear Wall in a Steel Frame

    , M.Sc. Thesis Sharif University of Technology Sarmadi, Shayan (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    Seismic loads are still a challenge for structures and engineers invent and provide seismic resisting systems to resist better against it. Concrete shear walls are well-known seismic resisting system that has had an acceptable performance in occurred seismic events. This system costs noticeable amount of time and material. Fiber-reinforced concretes can be useful to reduce negative effects and provides more positive effects like tensile strength, ductility, impact resisting and etc. Also changes in wall appearance such as corrugating helps to improve shear wall performance as it improves other kinds of plates and shell shaped members in structures. In this thesis, the focus is on “corrugated... 

    Analyzing and Modeling of Semi-hinged Connections in Steel Structure

    , M.Sc. Thesis Sharif University of Technology Haji kazemi, Mohsen (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    Double angle connections, which are welded to the beam web and bolted to the column flange, are usually used to make hinged or semi-hinged connections. Several models are presented in this study whose geometrical properties are different. The finite element software package is used to develop the finite element analysis of the connections. An analytical method is presented that can be used to determine the behavior and deformation for this type of connection. The correctness of Moment-rotation curves of finite element analysis for each connection has been ascertained by comparison, using analytical technique; and a very good agreement has been obtained  

    Dynamic Behavior Beam and Plate on Foundation under Moving Mass

    , Ph.D. Dissertation Sharif University of Technology Ghannadiasl, Amin (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    The behavior of a beam under moving mass has been always interested in the dynamic of structures. In this study, the dynamic response of beam and plate with general boundary conditions under moving mass were investigated using the Dynamic Green Function. Since the majority of previous studies did not consider the Coriolis acceleration, therefore, this acceleration was used in the present study. Boundary conditions are modeled by the rotational and translational restraint. By moving close to the spring constants of the rotational and translational restraint to extreme values (zero and/or infinity), the boundary conditions can be attained for the desired combinations of end boundary conditions... 

    Seismic Evaluation and Quantification of Seismic Performance Factors of Disposable Knee Bracing Frames

    , M.Sc. Thesis Sharif University of Technology Nobahar, Elnaz (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    Nowadays, Braced Frames systems are prevalent as a structural resisting lateral loads. One of the most crucial prominent of them is Disposable Knee Bracing (DKB). In such a system, braces provide stiffness, while the link elements play an important role as an energy-absorbing fuse to dissipate energy by plastic deformation. In this research, bracing frames consist of shear and/or flexural link elements. The experimental results reveal that hysteresis behavior of link elements remains constant till specific rotation. After that, sharply decrease due to crack failure of these elements occurs. This specific rotation has been reported between 0.06 to 0.08 Rad. Seismic performance factors such as... 

    Using Finite Element Method for Analyzing the Performance of Low Yield Point Steel Plate Shear Wall

    , M.Sc. Thesis Sharif University of Technology Jebelli, Houtan (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    Steel plate shear walls are lateral load resisting systems, especially against earthquake excitation. They are constructed with or without stiffeners. Stiffened walls are more ductile than without stiffeners walls. In this research, nine thin steel plate shear walls models were considered in three groups of 5story, 01story and 05 story walls. In each group different yield point steel for the infill plate was used. The results showed that, using low yield point(LYP) steel will increase energy dissipation of models up to %36. LYP also improve shear capacity of models up to %96. The results showed that using LYP will cause lower lateral displacement in models  

    A Parametric Study on Application and Analysis of Beam to Column "Reversed Channel" Connection in Tubular Systems

    , M.Sc. Thesis Sharif University of Technology Kokabi, Sina (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    Today steel tubular systems are used more than before, especially in recent years. A difficulty with this type of systems is making beam to column connections using bolts due to no access to holes of bolts from the inside of tube or hollow circular column. Reverse channel connection is devised and introduced to prevail this problem. Access to holes in this connection is from the inside of channel. In this connection, the web of the channel is connected to steel beam using bolts and the two legs of channel is welded to face of tube column.
    This type of connection does include some innovations; not too many researchers work on different versions of this connection. This thesis provides an... 

    Parametric Study of Concrete Connection Retrofitted by Steel Jacketing

    , M.Sc. Thesis Sharif University of Technology Makiabadi, Reza (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    This study investigates the cyclic experimental behavior of damaged exterior reinforced concrete beam–column joint specimens retrofitted with the proposed technique using steel elements called steel prop and curb. The technique is usable for local and global strengthening of reinforced concrete frames. Four half-scale RC joints were tested under the cyclic loading; two control specimens with the different beam heights were loaded up to their ultimate strength and this was followed by retrofitting of these damaged specimens as new specimens and tested again under the same loading system. This study indicate the importance of some parameters such as friction , jacket place , thickness of plate... 

    Investigating of the Behavior of the Column Base Plate with Eccentirisity Using FEM

    , M.Sc. Thesis Sharif University of Technology Moeini, Amin (Author) ; Vafaei, Abolhassan (Supervisor) ; Mofid, massoud (Co-Advisor)
    Abstract
    Base plate is one of the crucial elements in steel structures which transfer force from column to foundation and also prevent stress concentration in jointing area between them. For investigating the behavior of base plate under different caseloads such as axial, transverse and earthquake loads, it is necessary to consider all the involved elements including column, base plate, foundation, anchor rods and also interaction between these elements. In this study the connection between column and base plate, base plate and foundation are analyzed thoroughly. The behavior of base plate with a box type column with and without stiffener under the static loads is analyzed using finite element... 

    Investigation on the Effect of Existence of Gusset Plate in Moment-otation Behavior of Double Angle Connection in Braced Frames

    , M.Sc. Thesis Sharif University of Technology Tabkhi Wayghan, Amir Reza (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    Double web angle connection is one of the most simple connections in fabrication in simple frame structural systems. In common design procedures for this type of structural system, it is assumed that double web angle connection behaves as a simple connection, but in this system when bracing used, gusset plates of bracing are connected to top and bottom of double web angle connection, or just in top or bottom, and these gusset plates restraint beam to rotate at the places where it is connected to column. Restraning rotation of beam against column in beam to column connection, may change the classification of connection from simple connection to semi-rigid or even rigid connection. In this... 

    Nonlinear Behavior of Buckling Knee Bracing and a New Design Method for Multi Story Structures

    , M.Sc. Thesis Sharif University of Technology Izadi, Mohammad Reza (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    New CKB system is implemented into the multistory frames and investigated how its ductility and energy absorption will be changed if its bracings are able to buckle.buckling braces can improve energy absorption of lateral systems with their post-buckling characteristics through cyclic motions of frames.in proceeding,Nonlinear behavior of multi-story CKB systems within a non-dimensional desigh graphs is presented.application of multi-linear behavior of these systems are controlled by checking their ductility demands and their capacity. Nonlinear dynamic response of multi-story CKB system is analyzed through FEM softwares and presente through curves with which designers can calculate... 

    Seisimc Performance of Dutile End Diaphragms For Slab-on-girder Steel Bridges

    , M.Sc. Thesis Sharif University of Technology Mareki, Hasan (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    This thesis illustrates the typical seismic retrofitting of bridges using a model governing transverse seismic response of retrofitted bridges by simplified analytical models of the end diaphragms based on the fundamental dynamic concept as well as previous research works. For three types of ductile diaphragm devices such as Eccentrically Braced Frames (EBF), Triangular-plate Added Damping and Stiffness Devices (TADAS) and Chevron Knee Bracing (CKB)and Shear Panel System(SPS), finite element nonlinear analytical models are developed in separate flexural and shear yielding modes, and the capability of the proposed finite element models is ascertained.The IDA (Incremental Dynamic Analyses) are...