This paper presents highly efficient cable erection equipments and methods related to the construction of super-long-span bridges, construction technology of high towers and, technology for offshore foundations curren...This paper presents highly efficient cable erection equipments and methods related to the construction of super-long-span bridges, construction technology of high towers and, technology for offshore foundations currently developed through a R&D on accelerated and cost-saving construction technology for long-span cable bridges to secure our international competitiveness. In the field of cable erection technology, AS and PPWS equipments for highly efficient erection of cable longer than 2000 m, world-class clamping bolt tensioning equipment and shape control system for super-long cable are under development. The technologies developed in the domain of construction of towers are tapered slip form system for the construction of 400 m high tower, shape and erection precision control of elevated tower and, lightweight and modular formwork for slip form system. In the domain of foundation construction, remote controlled survey equipment and analysis system for water-depth of 100 m and depth of 50 m, prediction and evaluation technology of optimal load carrying capacity and settlement complying with international standard and, highly efficient hybrid foundation construction technology suitable for ground acceleration of 0.5 g and deep soft soil are currently developed.展开更多
In the process of unprecedented urbanization in contemporary China, a great many of Chinese cities have witnessed a rapid expansion of urban scale to different degrees. With the continuous compilation, amendment and e...In the process of unprecedented urbanization in contemporary China, a great many of Chinese cities have witnessed a rapid expansion of urban scale to different degrees. With the continuous compilation, amendment and enforcement of urban planning, the functional structure, spatial environment, street patterns and textures and even the social aspect of cities have changed conspicuously, all of which have directly happened to the spatial forms of the dimension, or even the multi-dimension of a certain city. By describing and analyzing the structure, evolution and explicit tokens of the spatial forms of cities, this thesis attempts to set up a model of factors that affect urban forms, as well as discuss the attributes, protection, adjustment and development-potential of urban land closely associated with forms. In addition, on the basis of the professional features for urban design to participate in the modeling and construction-management of desirable spatial forms of cities, the author has put forward technical measures for quantitatively appraising and analyzing the large-scaled spatial forms of cities, thus offering technical support to municipal governments and management departments of planned construction.展开更多
The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by...The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by forming defects in the transitional region.In this work,the feasibility of controlling forming defects and improving the process forming limit by adjusting die parameters is explored through finite element（FE） simulation.It is found that the common cavum and folding defects in the transitional region are significantly influenced by the fillet radii of left rib and middle rib,respectively.The cavum and folding defects can be effectively controlled by increasing the fillet radii of left rib and middle rib,respectively.The process forming limits considering forming defects in the transitional region are determined by the stepwise searching method under various die parameters.Moreover,the relationship between the process forming limit and die parameters is developed through the response surface methodology（RSM）.The developed RSM models suggest that increasing the fillet radii of left and middle ribs is effective to improve the process forming limit during local loading forming of rib-web components.The results will provide technical basis for the design of die parameters and the reduction amount,which is of great importance to control forming defects and improve the process forming limit in local loading forming of Ti-alloy large-scale rib-web components.展开更多
文摘This paper presents highly efficient cable erection equipments and methods related to the construction of super-long-span bridges, construction technology of high towers and, technology for offshore foundations currently developed through a R&D on accelerated and cost-saving construction technology for long-span cable bridges to secure our international competitiveness. In the field of cable erection technology, AS and PPWS equipments for highly efficient erection of cable longer than 2000 m, world-class clamping bolt tensioning equipment and shape control system for super-long cable are under development. The technologies developed in the domain of construction of towers are tapered slip form system for the construction of 400 m high tower, shape and erection precision control of elevated tower and, lightweight and modular formwork for slip form system. In the domain of foundation construction, remote controlled survey equipment and analysis system for water-depth of 100 m and depth of 50 m, prediction and evaluation technology of optimal load carrying capacity and settlement complying with international standard and, highly efficient hybrid foundation construction technology suitable for ground acceleration of 0.5 g and deep soft soil are currently developed.
基金Supported by the National Key Technology Research and Development Program of China (Grant Nos. 2006BAJ03A04, 2006BAJ4B067)
文摘In the process of unprecedented urbanization in contemporary China, a great many of Chinese cities have witnessed a rapid expansion of urban scale to different degrees. With the continuous compilation, amendment and enforcement of urban planning, the functional structure, spatial environment, street patterns and textures and even the social aspect of cities have changed conspicuously, all of which have directly happened to the spatial forms of the dimension, or even the multi-dimension of a certain city. By describing and analyzing the structure, evolution and explicit tokens of the spatial forms of cities, this thesis attempts to set up a model of factors that affect urban forms, as well as discuss the attributes, protection, adjustment and development-potential of urban land closely associated with forms. In addition, on the basis of the professional features for urban design to participate in the modeling and construction-management of desirable spatial forms of cities, the author has put forward technical measures for quantitatively appraising and analyzing the large-scaled spatial forms of cities, thus offering technical support to municipal governments and management departments of planned construction.
基金the support of the National Natural Science Foundation of China(Nos.51605388,51675433)111 Project(B08040)+2 种基金the Research Fund of the State Key Laboratory of Solidification Processing(NWPU)in China(Grant No.131-QP-2015)the Fundamental Research Funds for the Central Universitiesthe Open Research Fund of State Key Laboratory of Materials Processing and Die&Mold Technology at Huazhong University of Science and Technology
文摘The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by forming defects in the transitional region.In this work,the feasibility of controlling forming defects and improving the process forming limit by adjusting die parameters is explored through finite element（FE） simulation.It is found that the common cavum and folding defects in the transitional region are significantly influenced by the fillet radii of left rib and middle rib,respectively.The cavum and folding defects can be effectively controlled by increasing the fillet radii of left rib and middle rib,respectively.The process forming limits considering forming defects in the transitional region are determined by the stepwise searching method under various die parameters.Moreover,the relationship between the process forming limit and die parameters is developed through the response surface methodology（RSM）.The developed RSM models suggest that increasing the fillet radii of left and middle ribs is effective to improve the process forming limit during local loading forming of rib-web components.The results will provide technical basis for the design of die parameters and the reduction amount,which is of great importance to control forming defects and improve the process forming limit in local loading forming of Ti-alloy large-scale rib-web components.
