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On the optimization of vent arrangement in a subway station
, Article Applied Mechanics and Materials ; Volume 232 , 2012 , Pages 620-624 ; 16609336 (ISSN) ; 9783037855140 (ISBN) ; Vakilimoghaddam, F ; Neishapouri, R ; Sharif University of Technology
2012
Abstract
Toxic gases resulted from fire events in subways stations are more dangerous than high temperature radiation from it. So, a well designed smoke exhaust system must be installed in subway station to control the smoke's propagation and discharging. Smoke extraction in subway station depends on the duct laid above the ceiling, so vents are situated in the same level of platform layer's ceiling. If subway station catches fire, smoke will cumulate in smoke reservoirs at the beginning and mechanical fan cannot exhaust any smoke in this process. In This paper, FDS 5.0 is used to simulate smoke's movement in a side platform of an actual subway station in case of a fire. Simulations are carried out...
Timetable optimization for maximum usage of regenerative energy of braking in electrical railway systems
, Article SPEEDAM 2010 - International Symposium on Power Electronics, Electrical Drives, Automation and Motion, 14 June 2010 through 16 June 2010 ; June , 2010 , Pages 1218-1221 ; 9781424449873 (ISBN) ; Fekri Moghadam, M ; Mokhtari, H ; Sharif University of Technology
2010
Abstract
Research projects in urban transportation systems require proper simulation softwares. Such softwares are the basic requirements of any kind of study in electrical transportation systems. Due to high energy consumption of these systems, studies for its optimization are challenging and necessary. In this paper an optimized timetable of trains? movement is proposed in order to completely utilize the regenerative energy of trains? braking in stations. A sample subway system is simulated and Genetic algorithm is used as an optimization method. The effect of headway and reserve times on the amount of energy consumption is studied and an optimized reserve time set is found for the sample system....
Study on the influence of closely crossing tunnel on existing underground subway station by 3d-fem models
, Article World Tunnel Congress, WTC 2019 and the 45th General Assembly of the International Tunnelling and Underground Space Association, ITA-AITES 2019, 3 May 2019 through 9 May 2019 ; 2019 , Pages 6140-6150 ; 9781138388659 (ISBN) ; Asgarpanah, M. R ; Sharif University of Technology
CRC Press/Balkema
2019
Abstract
The increase of underground space applications, as a solution for congested urban areas makes it inevitable to cross closely spaced underground structures. The analysis of new TBM EPB-bored tunnel under existing underground station was conducted by 3D finite element method. The influence of new tunneling was investigated on the deformation and moments of final lining of existing underground station. The effectiveness of interaction analysis depends on factors such as station overburden, existing station supporting stiffness and traffic loads. In this paper, a parametric study was conducted to study ground movements and lining moments. It is shown that moment increase is significant when the...
Study on the influence of closely crossing tunnel on existing underground subway station by 3d-fem models
, Article World Tunnel Congress, WTC 2019 and the 45th General Assembly of the International Tunnelling and Underground Space Association, ITA-AITES 2019, 3 May 2019 through 9 May 2019 ; 2019 , Pages 6140-6150 ; 9781138388659 (ISBN) ; Asgarpanah, M. R ; Sharif University of Technology
CRC Press/Balkema
2019
Abstract
The increase of underground space applications, as a solution for congested urban areas makes it inevitable to cross closely spaced underground structures. The analysis of new TBM EPB-bored tunnel under existing underground station was conducted by 3D finite element method. The influence of new tunneling was investigated on the deformation and moments of final lining of existing underground station. The effectiveness of interaction analysis depends on factors such as station overburden, existing station supporting stiffness and traffic loads. In this paper, a parametric study was conducted to study ground movements and lining moments. It is shown that moment increase is significant when the...
Behavior of Underground Passagway and Subway Station for Earthquake Loads
, M.Sc. Thesis Sharif University of Technology ; Sadaghiani, Mohammad Hossein (Supervisor)
Abstract
A brief overview of the proposed research, its aims, engineering relevance and applications Underground space has long been exploited through the history to fulfill different human necessities. Underground facilities built in areas subject to earthquake activity must withstand both seismic and static loads. Some underground structures have experienced significant damage in recent large earthquakes. Tehran is located in seismic zone and investigation and research on the subject has significant role in design and construction of underground spaces for earthquake loads. Underground structures are complex structures which consist of different parts Such as passage way and platform space. Passage...
Dynamic Analysis of Mashhad Line 2 Subway Structure under Internal Blast Loading
, M.Sc. Thesis Sharif University of Technology ; Sadaghiani, Mohammad Hossein (Supervisor)
Abstract
Public transit system has become one of the targets of terrorist attacks using explosives, examples of which include the 1995 attack on Paris subway and the 2004 attack on Moscow subway. Under the present context of intense threats of terrorist attacks on subway systems in metropolitan areas around the world, explicit three-dimensional Finite Element method was used to investigate the dynamic response and damage of subway structures under internal blast loading. The study was motivated by the fact that explosion in subway structure may not only cause direct life loss, but also damage the subway structure and lead to further loss of lives and properties. The study used the Mashhadsubway...
Designing fire scenarios for subway stations and tunnels based on regional approach
, Article Advanced Materials Research, 16 September 2011 through 18 September 2011 ; Volume 433-440 , Septembe , 2012 , Pages 983-991 ; 10226680 (ISSN) ; 9783037853191 (ISBN) ; Maddahin, R ; Afshin, H ; Farhanie, B ; Sharif University of Technology
Abstract
Development of cities as well as population growth causes to development of public transportation especially subway lines. The high capacity besides the high speed in transportation makes them the popular transportation system. Fire is the one of the most important issues that may occur in subways. The difference in flame size, emissionheat, smoke and pollutants generation of subway fires attracts an especial attention of fire investigators. The emergency ventilation of subways in the case of fire should have the ability of discharging heat, smoke and pollutants from passenger escape route and preparing a safe place for a specific duration. The optimal performance of emergency ventilation...
An innovative method of large space underground construction in soft and shallow ground using concrete arch pre-supporting system, CAPS method
, Article ITA-AITES World Tunnel Congress 2016, 22 April 2016 through 28 April 2016 ; Volume 1 , 2016 , Pages 548-557 ; 9781510822627 (ISBN) ; Sharif University of Technology
Society for Mining, Metallurgy and Exploration
Abstract
Construction of underground structures in urban areas is a very challenging work. There are generally two methods of construction, an open cut-and-cover and underground method. To eliminate the subsurface and surface disturbance and street traffic problems, underground method is preferred. The stress redistribution caused by underground excavation induces movements and deformation in the earth mass and ultimately at the ground surface. This is more pronounced in large space excavations. Generally pre-supporting system is used to control ground deformation and thus enhance its stability. In this paper an innovative pre-supporting system is presented. Concrete Arch Pre-supporting System (CAPS)...
Study on the effect of a new construction method for a large span metro underground station in Tabriz-Iran
, Article Tunnelling and Underground Space Technology ; Volume 25, Issue 1 , 2010 , Pages 63-69 ; 08867798 (ISSN) ; Dadizadeh, S ; Sharif University of Technology
2010
Abstract
A method for construction of large underground spaces based on a new pre-supporting system is introduced. In this paper Mansour Station, in Line 1 of Tabriz Metro (Tabriz Urban Railway Organization, TURO); Iran has been studied using this method. Mansour Station have some special characteristics such as shallow depth, soft surrounding soil, wide span and heavy street traffic, thus requires a method of underground construction that can control the stability of the underground space and the ground settlement. This method includes a pre-supporting system that is called Concrete Arch Pre-supporting System (CAPS). Construction of CAPS is mainly based on construction method of old Iranian small...
Optimizing and synchronizing timetable in an urban subway network with stop-skip strategy
, Article Journal of Rail Transport Planning and Management ; Volume 22 , 2022 ; 22109706 (ISSN) ; Shafahi, Y ; SafariTaherkhani, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Stop-skipping and timetable synchronization are two effective strategies to reduce total passengers’ travel time in a transit network for subway operation. However, the majority of studies conducted on the topic do not consider stop-skipping strategy and timetable synchronization simultaneously. Thus, this article proposes a mixed-integer programming model considering both strategies simultaneously. The model is based on passenger smart-card data concerning the trains’ capacity to minimize total passengers’ waiting time and in-vehicle time and maximize the number of passengers who successfully reach their destination in a specific study horizon. Since increasing the number of trains,...
Numerical modeling of ground settlement control of large span underground metro station in Tehran Metro using Central Beam Column (CBC) structure
, Article Tunnelling and Underground Space Technology ; Volume 28, Issue 1 , 2012 , Pages 1-9 ; 08867798 (ISSN) ; Sadaghiani, M. H ; Ahmadi, M. M ; Sharif University of Technology
Abstract
The ground surface settlement caused by underground excavation is an important matter in urban development. The settlement control of large span underground station in Tehran Metro is investigated using a full three-dimensional (3-D) finite element analysis. A method of underground construction by increasing the rigidity of the supporting system using Central Beam Column (CBC) structure is introduced. In construction of large underground space, effect of presence of CBC structure is compared to a case without CBC structure. The CBC structure increases the rigidity of supports and decrease the stress concentration and displacement in supporting system. It generally decreases the soil...