摘要：
Health monitoring system is very important for the safety of long-span prestressed concrete cable-stayed bridge during its operation period. The normal method, system design principle, and main monitoring contents for long-span prestressed concrete cable-stayed bridges were introduced based on the domestic and overseas research status. Taking the EHuang Yangtze River Bridge as a case study, this paper introduced the key role of health monitoring system characterized by artificial regular monitoring to proper evaluation of health state of bridge on its operation period. The measured data of elevation, cable force, and deviation of tower etc on the periods of five years indicate that integral forced performance of EHuang Yangtze River Bridge during its operation period is favorable, and the various measured data can provide reference for shrinkage and creep parameter value of long-span prestressed concrete cable-stayed bridge.
作者机构：
[涂光亚; 颜东煌] School of Civil Engineering and Architecture, Changsha University of Science and Technology, Changsha 410004, China;[邵旭东] School of Civil Engineering, Hunan University, Changsha 410082, China
通讯机构：
[Tu, G.-Y.] S;School of Civil Engineering and Architecture, Changsha University of Science and Technology, China
会议论文集名称：
International Symposium mon Life-Cycle Performance of Bridge and Structures(桥梁和结构生命周期性能评估国际研讨会)论文集
关键词：
tower construction;layer construction method of three-time pouring and three-time tension;spatial finite element method;lower beam;concreting in lifts;supporting system
摘要：
With the development of the span lengths of cable-stayed bridges, there are more and more difficulties in the construction of tower. A new layer method of three-time pouring and three-time tension construction for the lower beam of long-span cable-stayed bridge tower is presented. The spatial finite element model considering the creep and shrinkage effects is established and applied to some engineering examples. And it is found that the residual stress near the seams due to the increase of the number of layered pouring can be reduced by adopting equitable construction program and rational tensioning force in order to avoid structural cracks. In order to ensure the safety of construction, mechanical and stability analysis are carried out and theoretical calculation results are compared with testing results.
摘要：
Pre-stressed concrete (PC) box-girder bridges are statically indeterminate structure in vertical and horizontal direction. In the cross section, forces on top flange, web and bottom flange are interactive. The spatial effects are obvious and the computed stress values based on the plane FE (finite element) are different from the actual stress. Hence, the PC combined elements with the concrete simulated by the layered degenerated shell elements and the pre-stressed steel simulated by the link elements are presented and element stiffness matrix have been deduced. A typical PC box-girder bridge with web cracks was analyzed to evaluate the mechanical behaviour and difference between spatial and plane models of box-girder bridges, which was modelled by plane FE and degenerated shell and link elements. The shortage for PC box-girder bridges in service designed by the principle tensile stress method that simulated by plane FE models and the main reason for the inclined cracks of concrete in web had been found. It was found that the spatial FE models were more suitable to analyze mechanical behaviour of PC box-girder bridges than the plane FE models.
作者机构：
[梁昔明; 朱灿] School of Information Science and Engineering, Central South University, Changsha 410083, China;[颜东煌] School of Bridge and Structure Engineering, Changsha University of Science and Technology, Changsha 410076, China;[朱灿] College of Traffic and Transportation Engineering, Changsha University of Science and Technology, Changsha 410076, China
通讯机构：
School of Information Science and Engineering, Central South University, China
