Sustainable performance is expected to become a major factor when examining the feasibility of a construction project in terms of its life cycle performance. The study on which this paper is based developed a simulati...Sustainable performance is expected to become a major factor when examining the feasibility of a construction project in terms of its life cycle performance. The study on which this paper is based developed a simulation model, using system dy- namics methodology, to assess the sustainable performance of projects. Three major factors are used to examine project sus- tainable performance (PSP): the sustainability of economic development (E), the sustainability of social development (S), and the sustainability of environmental development (En). Sustainable development ability (SDA) was used as a prototype to evaluate the degree of sustainable performance. The simulation software ‘ithink’ was used to help with the application of the model to a real life case. This paper explains and demonstrates the procedures used to develop the model and finally offers an approach for assessing the feasibility of a construction project in terms of its sustainable performance.展开更多
Lean construction has been newly applied to construction industry. The best performance of a project can be achieved through the precise definition of construction product, rational work break structure, lean supply c...Lean construction has been newly applied to construction industry. The best performance of a project can be achieved through the precise definition of construction product, rational work break structure, lean supply chain, decrease of resources waste, objective control and so forth. Referring to the characteristics of schedule planning of construction projects and lean construction philosophy, we proposed optimizing methodology of real-time and dynamic schedule of construction projects based on lean construction. The basis of the methodology is process reorganization and lean supply in construction enterprises. The traditional estimating method of the activity duration is fuzzy and random;however, a newly proposed lean forecasting method employs multi-components linear-regression, back-propagation artificial neural networks and learning curve. Taking account of the limited resources and the fixed duration of a project, the optimizing method of the real-time and dynamic schedule adopts the concept of resource driving. To optimize the schedule of a construction project timely and effectively, an intellectualized schedule management system was developed. It can work out the initial schedule, optimize the real-time and dynamic schedule, and display the schedule with the Gant Chart, the net-work graph and the space-time line chart. A case study was also presented to explain the proposed method.展开更多
Starting with the Ertan arch dam (240 m high, 3300 MW) in 2000, China successfully built a total of seven ultra-high arch dams over 200 m tall by the end of 2014. Among these, the ]inping 1 (305 m), Xiaowan (294...Starting with the Ertan arch dam (240 m high, 3300 MW) in 2000, China successfully built a total of seven ultra-high arch dams over 200 m tall by the end of 2014. Among these, the ]inping 1 (305 m), Xiaowan (294.5m), and Xiluodu (285.5 m) arch dams have reached the 300 m height level (i.e., near or over 300 m), making them the tallest arch dams in the world. The design and construction of these 300 m ultra-high arch dams posed significant challenges, due to high water pressures, high seismic de- sign criteria, and complex geological conditions. The engineering team successfully tackled these chal- lenges and made critical breakthroughs, especially in the area of safety control. In this paper, the author summarizes various key technological aspects involved in the design and construction of 300 m ultra- high arch dams, including the strength and stability of foundation rock, excavation of the dam base and surface treatment, dam shape optimization, safety design guidelines, seismic analysis and design, treatment of a complex foundation, concrete temperature control, and crack prevention. The experience gained from these projects should be valuable for future practitioners.展开更多
Sutong Bridge tower which is 300.4 m is the highest one in the world.The tower anchor area uses the steel-concrete composite structure,its structure and the stress mechanism are complex,so it must be paid more attenti...Sutong Bridge tower which is 300.4 m is the highest one in the world.The tower anchor area uses the steel-concrete composite structure,its structure and the stress mechanism are complex,so it must be paid more attention to the structure durable issue.The 300 m height makes the tower quite sensitive to the environmental factors such as wind and temperature.The wind resistance safety of tower in construction stage is especially important.In this paper,the design of composite structure is introduced.The key technologies of tower geometry control and wind resistance in construction stage are analyzed.展开更多
This paper,from three aspects including construction conditions,foundation design and construction,introduces some considerations in the designing of main-pylon foundations and some practical measures to deal with cer...This paper,from three aspects including construction conditions,foundation design and construction,introduces some considerations in the designing of main-pylon foundations and some practical measures to deal with certain unfavorable construction conditions,such as deep water,tidal effect,soft stratum and heavy traffic,during the construction of main-pylon foundations.展开更多
Long-span roof with span larger than height always has a complicated three-dimensional curve. Wind pressure on the roof is often influenced not only by the atmospheric turbulence, but also by the “signature” turbule...Long-span roof with span larger than height always has a complicated three-dimensional curve. Wind pressure on the roof is often influenced not only by the atmospheric turbulence, but also by the “signature” turbulence provoked in the wind by the structure itself. So it is necessary to study characteristics of flows around the roof. In this paper, three-dimensional numerical simulation of wind-induced pressure has been periormed on a long-span flat roof by means of Computational Fluid Dynamics (CFD) software ——FLUENT. The flow characteristics are studied by considering some parameters, such as wind direction, span-height ratio, roof pitch, flow characteristics, roughness of terrain. The simulation is based upon the Reynolds-averaged equations, in which Reynolds stress equation model (RSM) and SIMPLE technology, (Semi-Implieit Method for Pressure-Linked Equations) have been used. Compared with wind tunnel tests, the computational results have good agreement with the experimental data. It is proved that the results are creditable and the method is feasible.展开更多
This paper focuses on the independent design and construction of HYSY981. HYSY981,which China National Offshore Oil Corporation(CNOOC) possesses its intellectual property right,is brought forward by advanced research,...This paper focuses on the independent design and construction of HYSY981. HYSY981,which China National Offshore Oil Corporation(CNOOC) possesses its intellectual property right,is brought forward by advanced research,concept design and combined basic design. The key technologies are the researches concerning global design,system integration,platform positioning,global performance analysis,structural strength and fatigue analysis,environment effect assessment of South China Sea,basin test and tunnel test,and construction technology of platform. Core technology of design and construction for the 6th deep water semi-submersible rig is held. Independent detail design and construction are also accomplished. These have improved technology of key equipment for China offshore oil exploitation.展开更多
A nonmetal transportation port with soft soil foundation of Tianjin New Harbor failed during construction in 1997. The soil properties and geological changes before and after landslide were in- vestigated by in situ t...A nonmetal transportation port with soft soil foundation of Tianjin New Harbor failed during construction in 1997. The soil properties and geological changes before and after landslide were in- vestigated by in situ test means. The stability of the slope was estimated with several calculation methods, such as the simplified Bishop method and the non-circle analysis method. According to the investigation and analysis results, the factors that may cause the slope failure can be deter- mined as follows: excessive excavating, violating the normal construction procedure, excessive pore water pressure during earlier piling and sudden water-level fluctuation in front of the slope. Measures to improve the soil foundation for reconstructing the port include strengthening the failed slope with vibro sand piles, filling up the crushed stone layer, dividing the excavation into four steps and driving piles by larger intervals. The port now has been successfully reconstructed and begun operation.展开更多
In this paper, the design, construction and ocean testing of a wave energy conversion system are studied. Based on the motion characteristics of double buoys in ocean waves, a wave energy conversion system with perman...In this paper, the design, construction and ocean testing of a wave energy conversion system are studied. Based on the motion characteristics of double buoys in ocean waves, a wave energy conversion system with permanent magnet tubular linear generator (PMTLG) is proposed to convert ocean wave energy into electricity. The wave energy conversion system was installed in the Yellow Sea near Lianyungang, China. The ocean test re- suits indicate that it had dynamic and static performance, and obtained an expected amount of electricity. The calcu- lation result indicates the average output power was about 1 000 W, and the conversion efficiency from wave en- ergy into electricity was 1.4%. In addition, the wireless data communication, mechanics and oceanography were also discussed.展开更多
The objective of a bridge design is to produce a safe bridge that is elegant and satisfies all functionality requirements, at a cost that is acceptable to the owner. A successful bridge design must be natural, simple,...The objective of a bridge design is to produce a safe bridge that is elegant and satisfies all functionality requirements, at a cost that is acceptable to the owner. A successful bridge design must be natural, simple, original, and harmonious with its surroundings. Aesthetics is not an additional consideration in the design of a bridge, but is rather an integral part of bridge design. Both the structural configuration and the aesthetics of a bridge must be considered together during the conceptual design stage. To achieve such a task, the bridge design engineer must have a good understanding of structural theory and bridge aesthetics.展开更多
Some new innovative constructions and technologies for improvement of port structures are worked out and discussed. The aims of innovations are to increase structures' reliability, to decrease cost of construction an...Some new innovative constructions and technologies for improvement of port structures are worked out and discussed. The aims of innovations are to increase structures' reliability, to decrease cost of construction and maintenance, to simplify technology and cost of building. For these purposes either some main bearing elements or structures in whole are modified or improved. In particular different improved waterfront constructions as well as retaining walls and coastal protection (gravity, piled, sheet piling, etc.) for use in various soil conditions are outlined. One of them incorporates trapezoidal blocks forming columns, each block in the column contacts the others either with smaller or larger bases. Another design incorporates blocks that are constructed with holes ran through the centres of gravity of the blocks. Rigid cylinder element running through the holes of several adjacent blocks allows them to be joined forming large size units, The structure consisting of wedge form retaining wall is original but simple to construct, Some new designs based on perfection of sheet-piling walls (sheet piles with curvilinear cross-section having a form of semi-rings) are proposed for different applications. Proposals on modernization of some traditional structures and technologies are discussed.展开更多
Sutong Bridge,as a world-record cable-stayed bridge with its main span exceeding 1 000 m constructed in Yangtze River estuary region in China,is located at a site with complicated hydrologic conditions and poor geotec...Sutong Bridge,as a world-record cable-stayed bridge with its main span exceeding 1 000 m constructed in Yangtze River estuary region in China,is located at a site with complicated hydrologic conditions and poor geotechnical conditions and therefore,scour protection will be a decisive factor for ensuring smooth and successful construction of this bridge.This paper,starting from structural description of deep-water group pile foundation,analyzes impact to the bridge safety introduced by scour and its protection and further presents different solutions of scour protection for foundation structures of this bridge.展开更多
In order to improve the efficiency of EPS integral thermal insulation building design and optimize the construction process of insulation construction, this paper uses experiment parts and simulation form to design th...In order to improve the efficiency of EPS integral thermal insulation building design and optimize the construction process of insulation construction, this paper uses experiment parts and simulation form to design the thermal insulation construction process, and evaluates the effect of heat preservation. Based on the finite element theory this paper designs adding process of insulation material EPS in the thermal insulation layer, and establishes the radiation heat conduction model of EPS material, finally obtains the solid heat conduction equation. Finally this paper uses ANSYS software to do simulation on the strength and temperature of EPS construction, and evaluates the quality of construction works, which provides technical reference for the design of integrated thermal insulation buildings.展开更多
Due to the use of mechanical and electrical equipments in different buildings during construction phase, energy consumption produces large amounts of carbon emissions.Based on the energy use of China, we established a...Due to the use of mechanical and electrical equipments in different buildings during construction phase, energy consumption produces large amounts of carbon emissions.Based on the energy use of China, we established a formula that was applicable to carbon-emission calculation, and discussed carbon-emission characteristics of concrete structures and steel construction.Owing to the difference of electrical and mechanical equipment used in construction phase, the results show that under the same conditions, the carbon emission intensity of a concrete structure building is much higher than that of a steel building.At last, we also put forward some emission reduction measures based on the calculation data of different buildings.展开更多
基金Project supported by the Research Grant Council of Hong Kong,China
文摘Sustainable performance is expected to become a major factor when examining the feasibility of a construction project in terms of its life cycle performance. The study on which this paper is based developed a simulation model, using system dy- namics methodology, to assess the sustainable performance of projects. Three major factors are used to examine project sus- tainable performance (PSP): the sustainability of economic development (E), the sustainability of social development (S), and the sustainability of environmental development (En). Sustainable development ability (SDA) was used as a prototype to evaluate the degree of sustainable performance. The simulation software ‘ithink’ was used to help with the application of the model to a real life case. This paper explains and demonstrates the procedures used to develop the model and finally offers an approach for assessing the feasibility of a construction project in terms of its sustainable performance.
文摘Lean construction has been newly applied to construction industry. The best performance of a project can be achieved through the precise definition of construction product, rational work break structure, lean supply chain, decrease of resources waste, objective control and so forth. Referring to the characteristics of schedule planning of construction projects and lean construction philosophy, we proposed optimizing methodology of real-time and dynamic schedule of construction projects based on lean construction. The basis of the methodology is process reorganization and lean supply in construction enterprises. The traditional estimating method of the activity duration is fuzzy and random;however, a newly proposed lean forecasting method employs multi-components linear-regression, back-propagation artificial neural networks and learning curve. Taking account of the limited resources and the fixed duration of a project, the optimizing method of the real-time and dynamic schedule adopts the concept of resource driving. To optimize the schedule of a construction project timely and effectively, an intellectualized schedule management system was developed. It can work out the initial schedule, optimize the real-time and dynamic schedule, and display the schedule with the Gant Chart, the net-work graph and the space-time line chart. A case study was also presented to explain the proposed method.
文摘Starting with the Ertan arch dam (240 m high, 3300 MW) in 2000, China successfully built a total of seven ultra-high arch dams over 200 m tall by the end of 2014. Among these, the ]inping 1 (305 m), Xiaowan (294.5m), and Xiluodu (285.5 m) arch dams have reached the 300 m height level (i.e., near or over 300 m), making them the tallest arch dams in the world. The design and construction of these 300 m ultra-high arch dams posed significant challenges, due to high water pressures, high seismic de- sign criteria, and complex geological conditions. The engineering team successfully tackled these chal- lenges and made critical breakthroughs, especially in the area of safety control. In this paper, the author summarizes various key technological aspects involved in the design and construction of 300 m ultra- high arch dams, including the strength and stability of foundation rock, excavation of the dam base and surface treatment, dam shape optimization, safety design guidelines, seismic analysis and design, treatment of a complex foundation, concrete temperature control, and crack prevention. The experience gained from these projects should be valuable for future practitioners.
基金National Science and Technology Support Program of China(No.2006BAG04B04)
文摘Sutong Bridge tower which is 300.4 m is the highest one in the world.The tower anchor area uses the steel-concrete composite structure,its structure and the stress mechanism are complex,so it must be paid more attention to the structure durable issue.The 300 m height makes the tower quite sensitive to the environmental factors such as wind and temperature.The wind resistance safety of tower in construction stage is especially important.In this paper,the design of composite structure is introduced.The key technologies of tower geometry control and wind resistance in construction stage are analyzed.
基金National Science and Technology Support Program(No.2006BAG04B05)
文摘This paper,from three aspects including construction conditions,foundation design and construction,introduces some considerations in the designing of main-pylon foundations and some practical measures to deal with certain unfavorable construction conditions,such as deep water,tidal effect,soft stratum and heavy traffic,during the construction of main-pylon foundations.
文摘Long-span roof with span larger than height always has a complicated three-dimensional curve. Wind pressure on the roof is often influenced not only by the atmospheric turbulence, but also by the “signature” turbulence provoked in the wind by the structure itself. So it is necessary to study characteristics of flows around the roof. In this paper, three-dimensional numerical simulation of wind-induced pressure has been periormed on a long-span flat roof by means of Computational Fluid Dynamics (CFD) software ——FLUENT. The flow characteristics are studied by considering some parameters, such as wind direction, span-height ratio, roof pitch, flow characteristics, roughness of terrain. The simulation is based upon the Reynolds-averaged equations, in which Reynolds stress equation model (RSM) and SIMPLE technology, (Semi-Implieit Method for Pressure-Linked Equations) have been used. Compared with wind tunnel tests, the computational results have good agreement with the experimental data. It is proved that the results are creditable and the method is feasible.
基金National "863"Program "The study of 3000m depth water semi-submersible drilling rig key technology"( No.2006AA09A103)
文摘This paper focuses on the independent design and construction of HYSY981. HYSY981,which China National Offshore Oil Corporation(CNOOC) possesses its intellectual property right,is brought forward by advanced research,concept design and combined basic design. The key technologies are the researches concerning global design,system integration,platform positioning,global performance analysis,structural strength and fatigue analysis,environment effect assessment of South China Sea,basin test and tunnel test,and construction technology of platform. Core technology of design and construction for the 6th deep water semi-submersible rig is held. Independent detail design and construction are also accomplished. These have improved technology of key equipment for China offshore oil exploitation.
文摘A nonmetal transportation port with soft soil foundation of Tianjin New Harbor failed during construction in 1997. The soil properties and geological changes before and after landslide were in- vestigated by in situ test means. The stability of the slope was estimated with several calculation methods, such as the simplified Bishop method and the non-circle analysis method. According to the investigation and analysis results, the factors that may cause the slope failure can be deter- mined as follows: excessive excavating, violating the normal construction procedure, excessive pore water pressure during earlier piling and sudden water-level fluctuation in front of the slope. Measures to improve the soil foundation for reconstructing the port include strengthening the failed slope with vibro sand piles, filling up the crushed stone layer, dividing the excavation into four steps and driving piles by larger intervals. The port now has been successfully reconstructed and begun operation.
基金Supported by the National Natural Science Foundation of China(No.41076054)Special Foundation for State Oceanic Administration of China(No.GHME2011GD02)Scientific Research Foundation of Graduate School of Southeast University(No.YBJJ1416)
文摘In this paper, the design, construction and ocean testing of a wave energy conversion system are studied. Based on the motion characteristics of double buoys in ocean waves, a wave energy conversion system with permanent magnet tubular linear generator (PMTLG) is proposed to convert ocean wave energy into electricity. The wave energy conversion system was installed in the Yellow Sea near Lianyungang, China. The ocean test re- suits indicate that it had dynamic and static performance, and obtained an expected amount of electricity. The calcu- lation result indicates the average output power was about 1 000 W, and the conversion efficiency from wave en- ergy into electricity was 1.4%. In addition, the wireless data communication, mechanics and oceanography were also discussed.
文摘The objective of a bridge design is to produce a safe bridge that is elegant and satisfies all functionality requirements, at a cost that is acceptable to the owner. A successful bridge design must be natural, simple, original, and harmonious with its surroundings. Aesthetics is not an additional consideration in the design of a bridge, but is rather an integral part of bridge design. Both the structural configuration and the aesthetics of a bridge must be considered together during the conceptual design stage. To achieve such a task, the bridge design engineer must have a good understanding of structural theory and bridge aesthetics.
文摘Some new innovative constructions and technologies for improvement of port structures are worked out and discussed. The aims of innovations are to increase structures' reliability, to decrease cost of construction and maintenance, to simplify technology and cost of building. For these purposes either some main bearing elements or structures in whole are modified or improved. In particular different improved waterfront constructions as well as retaining walls and coastal protection (gravity, piled, sheet piling, etc.) for use in various soil conditions are outlined. One of them incorporates trapezoidal blocks forming columns, each block in the column contacts the others either with smaller or larger bases. Another design incorporates blocks that are constructed with holes ran through the centres of gravity of the blocks. Rigid cylinder element running through the holes of several adjacent blocks allows them to be joined forming large size units, The structure consisting of wedge form retaining wall is original but simple to construct, Some new designs based on perfection of sheet-piling walls (sheet piles with curvilinear cross-section having a form of semi-rings) are proposed for different applications. Proposals on modernization of some traditional structures and technologies are discussed.
基金National Science and Technology Support Program(No.2006BAG04B05)
文摘Sutong Bridge,as a world-record cable-stayed bridge with its main span exceeding 1 000 m constructed in Yangtze River estuary region in China,is located at a site with complicated hydrologic conditions and poor geotechnical conditions and therefore,scour protection will be a decisive factor for ensuring smooth and successful construction of this bridge.This paper,starting from structural description of deep-water group pile foundation,analyzes impact to the bridge safety introduced by scour and its protection and further presents different solutions of scour protection for foundation structures of this bridge.
文摘In order to improve the efficiency of EPS integral thermal insulation building design and optimize the construction process of insulation construction, this paper uses experiment parts and simulation form to design the thermal insulation construction process, and evaluates the effect of heat preservation. Based on the finite element theory this paper designs adding process of insulation material EPS in the thermal insulation layer, and establishes the radiation heat conduction model of EPS material, finally obtains the solid heat conduction equation. Finally this paper uses ANSYS software to do simulation on the strength and temperature of EPS construction, and evaluates the quality of construction works, which provides technical reference for the design of integrated thermal insulation buildings.
基金Funded by Regional Transportation Integration Technology of FAFU (No.Pytd 12006)Science and Technology project of Fujian Education Department (No.JB 11046)
文摘Due to the use of mechanical and electrical equipments in different buildings during construction phase, energy consumption produces large amounts of carbon emissions.Based on the energy use of China, we established a formula that was applicable to carbon-emission calculation, and discussed carbon-emission characteristics of concrete structures and steel construction.Owing to the difference of electrical and mechanical equipment used in construction phase, the results show that under the same conditions, the carbon emission intensity of a concrete structure building is much higher than that of a steel building.At last, we also put forward some emission reduction measures based on the calculation data of different buildings.