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
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
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
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,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
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
The construction of Three Gorges Project (TGP) is characterized by large construction scale,high construction intensity and complexity in technology.In view of various technical difficulties such as navigation in cons...The construction of Three Gorges Project (TGP) is characterized by large construction scale,high construction intensity and complexity in technology.In view of various technical difficulties such as navigation in construction period,two river closures,high-intensity concrete and earth-rock construction,high-intensity construction and demolition of RCC (roller compacted concrete) cofferdam in stage III and immediate navigation of double-line five-step shiplock after impoundment of reservoir,the scheme of river diversion during construction is adopted,namely "diversion in 3 stages,open channel navigation and cofferdam power generation".The practice and innovation achievements in river diversion during construction as well as earth-rock and concrete construction are presented emphatically.展开更多
Topology optimization is a powerful design approach that is used to determine the optimal topology in order to obtain the desired functional performance. It has been widely used to improve structural performance in en...Topology optimization is a powerful design approach that is used to determine the optimal topology in order to obtain the desired functional performance. It has been widely used to improve structural performance in engineering fields such as in the aerospace and automobile industries. However, some gaps still exist between topology optimization and engineering application, which significantly hinder the applica- tion of topology optimization. One of these gaps is how to interpret topology results, especially those obtained using the density framework, into parametric computer-aided design （CAD） models that are ready for subsequent shape optimization and manufacturing. In this paper, a new method for interpreting topology optimization results into stereolithography （STL） models and parametric CAD models is pro- posed. First, we extract the skeleton of the topology optimization result in order to ensure shape preser- vation and use a filtering method to ensure characteristics preservation. After this process, the distribution of the nodes in the boundary of the topology optimization result is denser, which will benefit the subsequent curve fitting. Using the curvature and the derivative of curvature of the uniform B-spline curve, an adaptive B-spline fitting method is proposed in order to obtain a parametric CAD model with the fewest control points meeting the requirement of the fitting error. A case study is presented to pro- vide a detailed description of the proposed method, and two more examples are shown to demonstrate the validity and versatility of the proposed method.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
The designing method and the supporting mechanism of both bolt and small cable anchor for full seam roadway in the weaker thick coal seam are systematically analyzed, and the construction technology and the supporting...The designing method and the supporting mechanism of both bolt and small cable anchor for full seam roadway in the weaker thick coal seam are systematically analyzed, and the construction technology and the supporting results are briefly summarized.展开更多
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 "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.
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.
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 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.
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.
文摘The construction of Three Gorges Project (TGP) is characterized by large construction scale,high construction intensity and complexity in technology.In view of various technical difficulties such as navigation in construction period,two river closures,high-intensity concrete and earth-rock construction,high-intensity construction and demolition of RCC (roller compacted concrete) cofferdam in stage III and immediate navigation of double-line five-step shiplock after impoundment of reservoir,the scheme of river diversion during construction is adopted,namely "diversion in 3 stages,open channel navigation and cofferdam power generation".The practice and innovation achievements in river diversion during construction as well as earth-rock and concrete construction are presented emphatically.
文摘Topology optimization is a powerful design approach that is used to determine the optimal topology in order to obtain the desired functional performance. It has been widely used to improve structural performance in engineering fields such as in the aerospace and automobile industries. However, some gaps still exist between topology optimization and engineering application, which significantly hinder the applica- tion of topology optimization. One of these gaps is how to interpret topology results, especially those obtained using the density framework, into parametric computer-aided design （CAD） models that are ready for subsequent shape optimization and manufacturing. In this paper, a new method for interpreting topology optimization results into stereolithography （STL） models and parametric CAD models is pro- posed. First, we extract the skeleton of the topology optimization result in order to ensure shape preser- vation and use a filtering method to ensure characteristics preservation. After this process, the distribution of the nodes in the boundary of the topology optimization result is denser, which will benefit the subsequent curve fitting. Using the curvature and the derivative of curvature of the uniform B-spline curve, an adaptive B-spline fitting method is proposed in order to obtain a parametric CAD model with the fewest control points meeting the requirement of the fitting error. A case study is presented to pro- vide a detailed description of the proposed method, and two more examples are shown to demonstrate the validity and versatility of the proposed method.
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The designing method and the supporting mechanism of both bolt and small cable anchor for full seam roadway in the weaker thick coal seam are systematically analyzed, and the construction technology and the supporting results are briefly summarized.
