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    Thermal performance evaluation of domed roofs

    , Article Energy and Buildings ; Volume 43, Issue 6 , June , 2011 , Pages 1254-1263 ; 03787788 (ISSN) Faghih, A. K ; Bahadori, M. N ; Sharif University of Technology
    2011
    Abstract
    Domed roofs have been used in Iran and many other countries to cover large buildings such as mosques, shrines, churches, schools. They have been also employed in other buildings like bazaars or market places in Iran due to their favorable thermal performance. The aim of this research is to study about domed roofs thermal performance in order to determine how they can be helpful in reducing the maximum air temperature of inside buildings during the warm seasons considering all parameters like air flow around them, solar radiation, radiation heat transfer with the sky and the ground as well as some openings on the building. The results of the study show that the thermal performance of the... 

    Three dimensional numerical simulation of air flow over domed roofs

    , Article NUMERICAL ANALYSIS AND APPLIED MATHEMATICS: International Conference on Numerical Analysis and Applied Mathematics, Corfu, 16 September 2007 through 20 September 2007 ; Volume 936 , 2007 , Pages 191-194 ; 0094243X (ISSN) ; 073540447X (ISBN); 9780735404472 (ISBN) Faghih Khorasani, A. R ; Bahadori, M. N ; Sharif University of Technology
    2007
    Abstract
    Using domed roofs to reduce building solar load in hot arid area is one of Iranian mechanical engineering masterworks. The first application of these roofs was to cover large buildings such as mosques, shrines, etc. However their thermal performance made them to be employed in other buildings like bazaars. The aim of this study was to determine the air pressure and velocity distribution over domed roofs, by employing numerical methods. The results of this study will be used as the first step for thermal performance evaluation of domed roofs. © 2007 American Institute of Physics  

    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... 

    Solar radiation on domed roofs

    , Article Energy and Buildings ; Volume 41, Issue 11 , 2009 , Pages 1238-1245 ; 03787788 (ISSN) Faghih Khorasani, A. R ; Bahadori, M.N ; Sharif University of Technology
    2009
    Abstract
    Solar radiation received and absorbed by four domed roofs was estimated and compared with that of a flat roof. The domed roofs all had the same base areas, and equal to that of the flat roof. One of the roofs considered was the dome of the St. Peter's Church in Rome. Compared with the other roofs considered, this dome had a higher aspect ratio. It was found that all domed roofs received more solar radiation than the flat roof. Considering glazed tiles to cover a selected dome in Iran and the dome of the St. Peter's Church, it was found that the solar radiation absorbed by these roofs is reduced appreciably. In the case of the dome of St. Peter's Church, the amount of radiation absorbed was... 

    Design & Analyze of Spherical Shell & Pointed Domes by Endurance Time Method

    , M.Sc. Thesis Sharif University of Technology Akbarzadeh Chiniforush, Alireza (Author) ; Esmaeilpour Estekanchi, Homayoon (Supervisor)
    Abstract
    Monumental structures are cultural and aesthetic bases in every nation, and our duty to maintaining these valuable remnants is obvious clearly. Meanwhile, the vaults have essential role as main elements in the Islamic architecture, and evaluation of their performance as well as retrofitting with regard to placing in earthquake-prone regions has high importance. Therefore, in this dissertation, performance of spherical and pointed domes are evaluated. Hence, 13 traditional Iranian domes are modeled with linear and non-linear material behavior in ABAQUS finite element software to verifying effect of their geometries in seismic performance. Base on Complex behavior of these models, they... 

    Thermal Performance Evaluation of Domed Roofs

    , Ph.D. Dissertation Sharif University of Technology Faghih, Ahmad Reza (Author) ; Bahadori Nezhad, Mehdi (Supervisor)
    Abstract
    Domed roofs were commonly used in buildings with large areas. These roofs played an important role in the Iranian architecture and had a great effect on the buildings cooling loads. Solar energy absorption causes the roof temperature to increase in comparison with its ambient atmosphere. Wind flow removes some of the heat from the roof, and the rest goes thorough the roof and enters the building.The eometrical configuration of these domed roofs causes the wind velocity to increase over them, resulting in an increase in the convection heat transfer coefficient. Also, the heat transfer of the roof is accentuated by the fact that the area of a domed configuration is considerably greater than a... 

    Shaking table tests on dome-roof adobe houses

    , Article Earthquake Engineering and Structural Dynamics ; Volume 46, Issue 3 , 2017 , Pages 467-490 ; 00988847 (ISSN) Bakhshi, A ; Ghannad, M ; Yekrangnia, M ; Masaeli, H ; Sharif University of Technology
    John Wiley and Sons Ltd  2017
    Abstract
    This paper presents the results of an experimental work in order to evaluate the performance of a novel proposed retrofitting technique on a typical dome-roof adobe building by shaking table tests. For this purpose, two specimens, scaled 2:3, were subjected to a total of nine shaking table tests. The unretrofitted specimen, constructed by common practice, is designed to evaluate seismic performance and vulnerability of dome-roof adobe houses. The retrofitted specimen, exactly duplicating the first specimen, is retrofitted based on the results obtained from unretrofitted specimen tests, and the improvement in seismic behavior of the structure is investigated. Zarand earthquake (2005) Chatrood... 

    Experimental investigation of air flow over domed roofs

    , Article Iranian Journal of Science and Technology, Transaction B: Engineering ; Volume 33, Issue 3 , 2009 , Pages 207-216 ; 10286284 (ISSN) Faghih Khorasani, A. R ; Bahador, M.N ; Sharif University of Technology
    2009
    Abstract
    Domed roofs have been used in Iran and many other countries to cover large buildings such as mosques, shrines, churches, schools, etc. However their favorable thermal performance has allowed them to be employed in other buildings like bazaars, or market places in Iran. In this investigation, wind pressure coefficients were determined experimentally for a domed roof model in a boundary layer wind tunnel. The model was a 1/10 scale model of the dome of an old school in the city of Yazd, in the central desert region of Iran. The model included a number of windows at the collar of the dome, and a hole on its apex. A total of 48 pressure tabs were employed to measure the air pressure at various... 

    On the Dynamic Response of Funicular Shells and Evaluation of the Behavior Factor

    , M.Sc. Thesis Sharif University of Technology Kadivar, Amin (Author) ; Mofid, Masoud (Supervisor)
    Abstract
    Dynamic behavior of space structures are of great complexities. On the event of severe earthquake these structures exhibit high resistance and on the other hand, their high rigidity and small deformation makes it necessary to pay attention to their dynamic behavior, especially when combined with other types of structural systems. Also due to lack of sufficient codes and references, their dynamic behavior is still unknown to a great extend. Among these kinds of structures, reinforced concrete double curvature shells, and especially funicular shells, are much more important than others. In this thesis, dynamic response of these kind of structures, especially reinforced concrete domes, in... 

    Seismic Behavior Modeling of An Arched-Roof Adobe Building

    , M.Sc. Thesis Sharif University of Technology Hasani, Mojahed (Author) ; Bakhshi, Ali (Supervisor) ; Ghannad, Mohammad Ali (Supervisor)
    Abstract
    Statistical studies indicate the fact that in Iran, like many other developing countries, a considerable percentage of houses are in the form of traditional buildings, and major losses due to recent earthquakes are because of masonry building collapse. In the early twentieth century in Iran every ten years a destructive earthquake has been occurred which has resulted in huge human casualties and economic losses. After the Bam 2003 earthquake, a team project was defined to investigate the behavior of rural houses with the aim of providing solutions to lessen seismic hazards, and the current study is the fifth phase of the following line of investigations. Among the existing kinds of rural... 

    Numerical Analysis of Adobe Structure with Dome Roof under Earthquake Excitation

    , M.Sc. Thesis Sharif University of Technology Khajehpour, Mehdi (Author) ; Ghannad , Mohammad Ali (Supervisor) ; Bakhshi, Ali (Co-Advisor)
    Abstract
    After the heart-rending earthquake in Bam and its severe losses, the engineering community forced to pay special attention to the seismic vulnerability of traditional structures. Therefore, with the aim of reducing of such devastations to minimum, a multi-phase research project was defined at Sharif University of Technology to study the vulnerability and retrofitting of these structures which the current study is the eighth phase of that series research. In the third and fourth phases of this project, a typical adobe building with dome roof was chosen for study making use of shaking table facilities. The tests included both un-retrofitted and retrofitted states and considerable seismic... 

    On the Performance Assessment and Parametric Study of Pre-stressed Concrete Doms Behavior

    , M.Sc. Thesis Sharif University of Technology Modarres Bostan Abad, Soheil (Author) ; Mofid, Masoud (Supervisor)
    Abstract
    Today, with the replacement of the old method of force-based design by the new method of performance-based design in structural and earthquake engineering, many structural and earthquake researchers have focused in their studies on this area. The performance-based design aims at enabling engineers to design structures with predictable performance. Designing space structures has particular complexities. In space structures, the failure of a structural member does not necessarily mean the failure of the entire structure, because the redistribution of power will occur between the adjacent members after the failure of a member and the structure can thus have further support capacity. Similarly,... 

    Evaluation of Seismic Performance of Adobe Dome-roof Structures Retrofitted by Steel Rods and Mesh Using Shaking Table Facility

    , M.Sc. Thesis Sharif University of Technology Yekrang, Mohammad (Author) ; Bakhshi, Ali (Supervisor) ; Ghannad, Mohammad Ali (Supervisor)
    Abstract
    Adobe buildings on one hand are very heavy and hence generate great amounts of inertia loads during earthquakes. Their response is also amplified in the high-frequency earthquake waves due to great stiffness. On the other hand, these structures proved vulnerable during past earthquakes because of low strength and ductility. Considering the fact that there are too many structures of this kind throughout the country and a majority of their residents are the poor, seismic retrofitting of these building should be taken as a priority rather than reconstruction. It is obvious that the proposed retrofitting technique should be simple, feasible and economical, as well. Among possible retrofitting... 

    Seismic Performance Assessment of Historical Structures and Presenting their Seismic Rehabilitation Plan ; a Case Study : Soltanieh Dome

    , M.Sc. Thesis Sharif University of Technology Asgari, Pouya (Author) ; Bakhshi, Ali (Supervisor)
    Abstract
    Preservation of historical monuments is a very important issue for future generations. The importance of this issue is doubled when we know that most of these buildings are traditionally built and do not have a single structure to withstand seismic loads. One of such buildings in our country is Bam Citadel, which was completely destroyed as the oldest brick building in the world during the 2003 Bam earthquake.In this project, we will try to find a model that can determine the structural behavior of the historical dome of Soltanieh for engineers in a case study. This building is a brick dome with a height of 48.5 meters and a diameter of 24.4 meters from the seventh century , which is unique... 

    Restoration of historical Al-Askari shrine. II: Vulnerability assessment by numerical simulation

    , Article Journal of Performance of Constructed Facilities ; Volume 30, Issue 3 , 2016 ; 08873828 (ISSN) Yekrangnia, M ; Aghababai Mobarake, A ; Sharif University of Technology
    American Society of Civil Engineers (ASCE) 
    Abstract
    This paper presents the results of a vulnerability assessment of the damaged Al-Askari shrine located in Samarra, Iraq by finite element analysis. Reliable material characteristics are derived using limited experimental data on this historical building in order to be utilized in the numerical models. It is concluded that the cracked piers are not vulnerable under the weight of the newly added dome. However, the cracks in the piers widen under design seismic loads, which results in unbalanced settlements in the piers and torsional cracks in the dome. The vulnerability of the minarets is more severe, necessitating heavy reinforcement at their bases and adequate anchorage to the masonry... 

    Seismic Evaluation and Rehabilitation of Historic Buildings: A Case Study about Soltaniyeh Dome

    , M.Sc. Thesis Sharif University of Technology Ghaemi, Mohammad Kazem (Author) ; Bakhshi, Ali (Supervisor)
    Abstract
    Health monitoring of historic structures because of their cultural and economic importance is of great interest; also modeling and investigating the behavior of these structures is needed in rehabilitation procedures. Soltaniye Dome is one of the important masterpieces of Persian-Islamic historic architecture which is constructed during 14th century (1302-1312 AD). The Soltaniye building has an octagonal framework and a great dome. The dome has a diameter of 25 meters and total height of structure is about 54 meters.In this study, the macro modeling of Soltaniye building is performed using finite element software. In order to verify the modeled structure, ambient vibration tests are... 

    Comparison of the effects of different implant apical designs on the magnitude and distribution of stress and strain in bone: A finite element analysis study

    , Article Journal of Long-Term Effects of Medical Implants ; Vol. 24, issue. 2-3 , 2014 , p. 109-120 Kadkhodazadeh, M ; Lafzi, A ; Raoofi, S ; Khademi, M ; Amid, R ; Movahhedy, M. R ; Torabi, H ; Sharif University of Technology
    Abstract
    Objectives: The aim of this study was to investigate the effects of implant design on the apex area and on stress and stress patterns within surrounding bone. Methods: Three commercially available implants with the same diameter (3.5 mm), same length (10-11 mm), and same complement abutment were selected for modeling as follows: (1) flat apical design with light tapering degree, (2) dome-shaped apical design with light tapering, and (3) flat apical design with intense tapering in one-third of the apical area. According to human cone-beam computed tomography (CBCT), the bone was modeled using a cortical thickness of 2 mm and cancellous bone. Forces of 100 N and 300 N in the vertical and 15°... 

    Investigation into the effects of weld zone and geometric discontinuity on the formability reduction of tailor welded blanks

    , Article Computational Materials Science ; Volume 59 , 2012 , Pages 158-164 ; 09270256 (ISSN) Abbasi, M ; Ketabchi, M ; Ramazani, A ; Abbasi, M ; Prahl, U ; Sharif University of Technology
    2012
    Abstract
    Numerous advantages of application of tailor welded blanks (TWBs) in automobile industry, namely reduction of weight, fuel consumption and air pollution, have made the manufacturers eager to investigate in this field. On the other hand, while experiments generally provide valuable information in regard with mechanical behaviors, but utilization of simulation methods has extended vastly due to time and cost saving issues. One challenging issue in numerically analyzing the forming behavior of transversely welded TWBs, welded by laser welding methods, has been the presence of weld zone. While some researchers believe that during simulation, the weld zone can be neglected due to its minority and... 

    Three dimensional numerical investigation of air flow over domed roofs

    , Article Journal of Wind Engineering and Industrial Aerodynamics ; Volume 98, Issue 3 , 2010 , Pages 161-168 ; 01676105 (ISSN) Faghih, A. K ; Bahadori, M. N ; Sharif University of Technology
    2010
    Abstract
    Domed roofs have been used in Iran and many other countries to cover large buildings such as mosques, shrines, churches, schools, etc. However their favorable thermal performance made them to be employed in other buildings such as bazaars, or market places, in Iran. The aim of this study was to determine the air pressure distribution over domed roofs, employing a numerical method. In this investigation, a three-dimensional model and a laminar inlet air flow were considered. The k-ε RNG method was employed for the turbulent flow simulation method. Simulation was run under three conditions of windows and a hole on top of the dome being open, or closed. The results were compared with the... 

    Explicit finite element modeling of wear within the patellofemoral joint in total knee replacement

    , Article 26th National and 4th International Iranian Conference on Biomedical Engineering, ICBME 2019, 27 November 2019 through 28 November 2019 ; 2019 , Pages 208-212 ; 9781728156637 (ISBN) Bahadoran, M ; Dorri Nokoorani, Y ; Barati, K ; Farahmand, F ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    Total knee replacement (TKR) surgery is one of the most successful and cost-effective procedures for treating knee injuries performed in orthopedics. However, the knee replacement revision surgery will probably be required after some years. Wear at the contact area between femoral metal component and the polyethylene inserts in TKR is recognized as one of the foremost causes of prosthesis failure and necessity of revision surgery. In the present study, focusing on the patellofemoral joint (PFJ), the wear at the contact area between the patellar and femoral components has been simulated employing the explicit finite element modeling. In this regard, common types of patellar component surface...