This paper investigates an open web truss joist (OWTJ) made of laminated </span><span><span style="font-family:Verdana;">veneer lumber (LVL) </span><i><span style="font-...This paper investigates an open web truss joist (OWTJ) made of laminated </span><span><span style="font-family:Verdana;">veneer lumber (LVL) </span><i><span style="font-family:Verdana;">Paraserianthes falctaria</span></i><span style="font-family:Verdana;"> as a prefabricated tim</span></span><span style="font-family:Verdana;">ber</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">concrete </span><span style="font-family:Verdana;">composite floor system. The four-point bending test showed that structura</span><span style="font-family:Verdana;">l performances of the OWTJ, conventional composite floor (CCF), and prefabricated composite floor (PCF) were similar. Although composite action was not developed as no lateral deformation was observed at the shear connectors, in</span><span style="font-family:Verdana;">stalling a concrete slab above the OWTJ can slightly increase the ductility</span><span style="font-family:Verdana;"> factor of the composite floor. Furthermore, a finite element model was developed, and the model proved to be suitable for simulating the structural performance of the composite floor.展开更多
When service ducts and cables are required to pass through the structural beams,it is a common practical solution to use composite beams with rectangular or circular openings.The fire safety standards in many countrie...When service ducts and cables are required to pass through the structural beams,it is a common practical solution to use composite beams with rectangular or circular openings.The fire safety standards in many countries have recommended design methods for composite beams without openings,while the design method for composite beams with web openings is not addressed yet.Due to the complicated distribution of temperature and stress around the openings in the web of the steel beam,extra complexity has been introduced in determination of the structural capability of the beam and the failure mode in fire.These failure modes generally occur at lower limiting temperatures than the solid beam with same size.It is recognized that the thickness of a reactive coating required to provide a given fire resistance to a composite beam with web openings is affected by the beam’s web thickness,opening configuration,the degree of the beam asymmetry and the structural utilization factor,as well as the nature of the proprietary fire protection itself.Therefore it is necessary that such beams are structurally evaluated taking into account all possible modes of structural failure under both ambient and fire conditions.It is also necessary for additional thermal data to be measured around the web openings and on the web posts from fire tests.The additional thermal data will be used in conjunction with a structural model to determine limiting temperatures of beams with web openings.Steel Construction Institute(SCI)has produced a structural analysis model referenced as report RT1356,which divides a composite beam with web openings into different stress blocks,and then analyses the global bending,vertical shear,local Vierendeel bending,web-post buckling etc.The Association for Specialist Fire Protection(ASFP)recommended the test protocol in the Yellow Book,to determine the temperature distribution around the openings and web post.This paper will discuss a series of fire tests having been carried out in the laboratory of EXOVA Warringtonfire to establish temperature distribution in composite beams with web openings.Test result shows that the distribution of temperature is product specific and strongly affected by opening configuration and opening distance.EXOVA Warringtonfire has also developed a sophisticated calculator,ThermCalc,for analyzing temperature and structural following the method presented in RT1356.Using ThermCalc,parametric study has been carried out,and the effect of load utilization factor,opening size,opening distance,slab depth,decking configuration etc.was investigated.展开更多
Height limitations are not uncommon in multi-storey buildings due to economic requirements and esthetical considerations. Substantial spaces are normally required to enable the passage of large pipes and ducts beneath...Height limitations are not uncommon in multi-storey buildings due to economic requirements and esthetical considerations. Substantial spaces are normally required to enable the passage of large pipes and ducts beneath steel beams leading to uneconomic floor heights. The most adopted solution for this issue is the use of steel beam web openings to provide the required space for services. These openings could lead to a significant decrease of the beam load carrying capacity depending on the adopted openings shape, size and location. These aspects motivated the present study based on FE simulations calibrated against numerical and test results. The results accuracy enabled a comprehensive parametric analysis of beams with web openings to be made focused on the profile size, web opening location, among others. The study also investigated the efficiency of longitudinal stiffeners welded at the opening region and benefits of using an adequate edge concordance radius in beams with rectangular and square openings. The obtained results showed the need of using welded longitudinal stiffeners in order to increase the beams ultimate load carrying capacity. This adoption can double or even triple the ultimate load of beams with rectangular and square opening heights equal to 0.75 H, respectively.展开更多
The lateral torsional buckling phenomenon often governs design of steel I-beams. Although web opening is often used to accommodate the required mechanical and piping works in buildings, its effect on the buckling inst...The lateral torsional buckling phenomenon often governs design of steel I-beams. Although web opening is often used to accommodate the required mechanical and piping works in buildings, its effect on the buckling instability is not considered in the design codes. In this paper, the effect of web opening on both lateral torsional buckling and local buckling behaviors has been investigated. A simply supported steel I-beam has been studied under uniform bending moment around the major axis. Buckling analysis has been performed using the finite element method. Linear regression analysis has been conducted for output data to formulate an equation for the critical moment including web opening effect. The results have shown a limited reduction in the lateral torsional buckling capacity and a significant reduction in the local buckling capacity.展开更多
According to the purpose of the opening and the structural designer, the shape of the web opening is decided. It is too easy to choose the shape of openings from regular shape whether it is circular or rectangular sha...According to the purpose of the opening and the structural designer, the shape of the web opening is decided. It is too easy to choose the shape of openings from regular shape whether it is circular or rectangular shape. The presence of openings in the web of steel beams decreases stiffness of the beam and introducing a larger deflection than in the steel web opening with solid opening. A steel beam with web opening is analyzed in this paper. ABAQUS software is using for analyzing nonlinear static and dynamic opening of steel beam with different position and supporting conditions.展开更多
There is a growing need for web-based geographic information systems for easy and fast dissemination, sharing, displaying and processing of spatial information. The tremendous growth in the use of web and open-source ...There is a growing need for web-based geographic information systems for easy and fast dissemination, sharing, displaying and processing of spatial information. The tremendous growth in the use of web and open-source geospatial resources has sparked development of web-based spatial applications to address multidisciplinary issues with spatial dimensions. This paper presents the integration of open-source geospatial tools and web technology to visualize and interact with spatial data using web browser. The goal of this paper is to implement a prototype system for web-based mapping by providing step-by-step instructions in order to encourage the eager developers and interested readers to publish their maps on the web with no prior technical experience in map servers. The implementation of mapping prototype shows the utilization of open-source geospatial tools which results in a rapid implementation with minimal or no software input cost.展开更多
Tourism in developing countries are some means of solving their economic problems and improving live standards of people and creates job opportunity for the host people in getting additional income and improve the dev...Tourism in developing countries are some means of solving their economic problems and improving live standards of people and creates job opportunity for the host people in getting additional income and improve the developments of the country. The result of tourism in terms of environmental, cultural, economic and social aspects has a greater effect for Ethiopia. Gondar, the center of Ethiopian art and culture, is famous in its many Imperial castles and the design and decoration of its churches. This land of castles and churches was founded by Emperor Fasiladas in 1930s and served as tourist attraction sites all over the world. The main challenge to attract international tourists in the study area is Scarce and insufficient promotion of the tourist attraction sites, Lack of broad information based on the internet about tourism information, and lack of organized information about tourism facilities & destinations. This study tries to identify tourist attraction elements of Gondor town and its surrounding area & to identify non spatial data’s essential for touristic activities to develop & propose a web based GIS portal for the improvement of tourism activity in the town. The main target of developing a web based GIS interactive map is to promote and improve tourism industry of the area. It has been produced using free and open source software’s for fast processing, displaying, sharing, and distribution of tourism information using world wide web. For the web services PHP, HTML script language and QGIS2leaflet plugins are used in the development of web GIS portal.展开更多
Aiming to solve the existing problems with the Quality Course,an EFL online course is developed with an Open Source Course Management System(CMS).The principles and strategies of designing and constructing the course ...Aiming to solve the existing problems with the Quality Course,an EFL online course is developed with an Open Source Course Management System(CMS).The principles and strategies of designing and constructing the course are discussed.The process of developing vocational college students'professional and social competence in the web-based environment is ex plored.Research results show the students are satisfied with the web-based EFL course and the teaching.展开更多
文摘This paper investigates an open web truss joist (OWTJ) made of laminated </span><span><span style="font-family:Verdana;">veneer lumber (LVL) </span><i><span style="font-family:Verdana;">Paraserianthes falctaria</span></i><span style="font-family:Verdana;"> as a prefabricated tim</span></span><span style="font-family:Verdana;">ber</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">concrete </span><span style="font-family:Verdana;">composite floor system. The four-point bending test showed that structura</span><span style="font-family:Verdana;">l performances of the OWTJ, conventional composite floor (CCF), and prefabricated composite floor (PCF) were similar. Although composite action was not developed as no lateral deformation was observed at the shear connectors, in</span><span style="font-family:Verdana;">stalling a concrete slab above the OWTJ can slightly increase the ductility</span><span style="font-family:Verdana;"> factor of the composite floor. Furthermore, a finite element model was developed, and the model proved to be suitable for simulating the structural performance of the composite floor.
文摘When service ducts and cables are required to pass through the structural beams,it is a common practical solution to use composite beams with rectangular or circular openings.The fire safety standards in many countries have recommended design methods for composite beams without openings,while the design method for composite beams with web openings is not addressed yet.Due to the complicated distribution of temperature and stress around the openings in the web of the steel beam,extra complexity has been introduced in determination of the structural capability of the beam and the failure mode in fire.These failure modes generally occur at lower limiting temperatures than the solid beam with same size.It is recognized that the thickness of a reactive coating required to provide a given fire resistance to a composite beam with web openings is affected by the beam’s web thickness,opening configuration,the degree of the beam asymmetry and the structural utilization factor,as well as the nature of the proprietary fire protection itself.Therefore it is necessary that such beams are structurally evaluated taking into account all possible modes of structural failure under both ambient and fire conditions.It is also necessary for additional thermal data to be measured around the web openings and on the web posts from fire tests.The additional thermal data will be used in conjunction with a structural model to determine limiting temperatures of beams with web openings.Steel Construction Institute(SCI)has produced a structural analysis model referenced as report RT1356,which divides a composite beam with web openings into different stress blocks,and then analyses the global bending,vertical shear,local Vierendeel bending,web-post buckling etc.The Association for Specialist Fire Protection(ASFP)recommended the test protocol in the Yellow Book,to determine the temperature distribution around the openings and web post.This paper will discuss a series of fire tests having been carried out in the laboratory of EXOVA Warringtonfire to establish temperature distribution in composite beams with web openings.Test result shows that the distribution of temperature is product specific and strongly affected by opening configuration and opening distance.EXOVA Warringtonfire has also developed a sophisticated calculator,ThermCalc,for analyzing temperature and structural following the method presented in RT1356.Using ThermCalc,parametric study has been carried out,and the effect of load utilization factor,opening size,opening distance,slab depth,decking configuration etc.was investigated.
文摘Height limitations are not uncommon in multi-storey buildings due to economic requirements and esthetical considerations. Substantial spaces are normally required to enable the passage of large pipes and ducts beneath steel beams leading to uneconomic floor heights. The most adopted solution for this issue is the use of steel beam web openings to provide the required space for services. These openings could lead to a significant decrease of the beam load carrying capacity depending on the adopted openings shape, size and location. These aspects motivated the present study based on FE simulations calibrated against numerical and test results. The results accuracy enabled a comprehensive parametric analysis of beams with web openings to be made focused on the profile size, web opening location, among others. The study also investigated the efficiency of longitudinal stiffeners welded at the opening region and benefits of using an adequate edge concordance radius in beams with rectangular and square openings. The obtained results showed the need of using welded longitudinal stiffeners in order to increase the beams ultimate load carrying capacity. This adoption can double or even triple the ultimate load of beams with rectangular and square opening heights equal to 0.75 H, respectively.
文摘The lateral torsional buckling phenomenon often governs design of steel I-beams. Although web opening is often used to accommodate the required mechanical and piping works in buildings, its effect on the buckling instability is not considered in the design codes. In this paper, the effect of web opening on both lateral torsional buckling and local buckling behaviors has been investigated. A simply supported steel I-beam has been studied under uniform bending moment around the major axis. Buckling analysis has been performed using the finite element method. Linear regression analysis has been conducted for output data to formulate an equation for the critical moment including web opening effect. The results have shown a limited reduction in the lateral torsional buckling capacity and a significant reduction in the local buckling capacity.
文摘According to the purpose of the opening and the structural designer, the shape of the web opening is decided. It is too easy to choose the shape of openings from regular shape whether it is circular or rectangular shape. The presence of openings in the web of steel beams decreases stiffness of the beam and introducing a larger deflection than in the steel web opening with solid opening. A steel beam with web opening is analyzed in this paper. ABAQUS software is using for analyzing nonlinear static and dynamic opening of steel beam with different position and supporting conditions.
文摘There is a growing need for web-based geographic information systems for easy and fast dissemination, sharing, displaying and processing of spatial information. The tremendous growth in the use of web and open-source geospatial resources has sparked development of web-based spatial applications to address multidisciplinary issues with spatial dimensions. This paper presents the integration of open-source geospatial tools and web technology to visualize and interact with spatial data using web browser. The goal of this paper is to implement a prototype system for web-based mapping by providing step-by-step instructions in order to encourage the eager developers and interested readers to publish their maps on the web with no prior technical experience in map servers. The implementation of mapping prototype shows the utilization of open-source geospatial tools which results in a rapid implementation with minimal or no software input cost.
文摘Tourism in developing countries are some means of solving their economic problems and improving live standards of people and creates job opportunity for the host people in getting additional income and improve the developments of the country. The result of tourism in terms of environmental, cultural, economic and social aspects has a greater effect for Ethiopia. Gondar, the center of Ethiopian art and culture, is famous in its many Imperial castles and the design and decoration of its churches. This land of castles and churches was founded by Emperor Fasiladas in 1930s and served as tourist attraction sites all over the world. The main challenge to attract international tourists in the study area is Scarce and insufficient promotion of the tourist attraction sites, Lack of broad information based on the internet about tourism information, and lack of organized information about tourism facilities & destinations. This study tries to identify tourist attraction elements of Gondor town and its surrounding area & to identify non spatial data’s essential for touristic activities to develop & propose a web based GIS portal for the improvement of tourism activity in the town. The main target of developing a web based GIS interactive map is to promote and improve tourism industry of the area. It has been produced using free and open source software’s for fast processing, displaying, sharing, and distribution of tourism information using world wide web. For the web services PHP, HTML script language and QGIS2leaflet plugins are used in the development of web GIS portal.
文摘Aiming to solve the existing problems with the Quality Course,an EFL online course is developed with an Open Source Course Management System(CMS).The principles and strategies of designing and constructing the course are discussed.The process of developing vocational college students'professional and social competence in the web-based environment is ex plored.Research results show the students are satisfied with the web-based EFL course and the teaching.
