Abstract:With the development of modern long-span cable-stayed Bridges, the on-site cable-stayed cable of steel strand has been more and more favored by designers because of its advantages such as no need for large cable-making, transportation, hoisting and tension traction equipment, and superior overall protective performance of the cable. As a load-bearing component of cable-stayed bridge, the steel strand cable-stayed cable is called the life cable of cable-stayed bridge, and its reliability is one of the key factors to determine the safety and reliability of cable-stayed bridge. This paper mainly introduces the reliability research of cable anchoring system in the process of design and improvement of OVM250 steel strand cable system. Through the design means of effectively improving the fatigue performance of cable anchoring assembly, the optimal design of cable anchoring unit is carried out to ensure the safety and reliability of cable anchoring assembly. The fatigue test of OVM250-139 cable anchoring assembly is further conducted The excellent fatigue resistance of OVM250 steel strand cable system was verified.

Abstract:Standardization is an important way to carry out product development, technical transformation, ensure product quality and improve product market competitiveness. At present, there is no product standard of wireless torsional stress measuring device, so the design of this device brings some uncertainty. Based on the study of the principle and application of torsional vibration measurement and the specification of relevant electronic products at home and abroad, this paper puts forward the standard design requirements of wireless torsional vibration stress measurement device. Based on this, a portable wireless torsional vibration stress measurement instrument is designed and developed. The discussion in this paper provides an important design basis for the developers of wireless torsional stress measurement instrument, and has important guiding significance for the engineers of torsional stress measurement.

Abstract:The steel bar connection technology is one of the key construction technologies in the prefabricated concrete structure, and the steel bar connection is generally carried out by grouting sleeve. In recent years, grouting sleeves have been used more and more in prefabricated building components in China, but the time of application in bridge is relatively short. This paper introduces the test and research of grouting sleeve bar connection technology in precast pier, mainly from the research background, connection structure and material properties, bond stress study, type test, seismic test of precast assembled column, etc.

Abstract:The main bridge of Aixihu Bridge in Nanchang is 30m+108m+30m three-span continuous tilting four-cable plane underbearing steel box tie pole arch bridge, and its suspender adopts OVM arch bridge suspender system. The system is a new type of boom system developed on the basis of the original boom, using a new PES(FD) low stress anti-corrosion system, a new waterproof structure system and a number of new structures such as the ball hinge device that can swing, to solve the problems of HDPE jacket cracking in a short time, water intake in the lower section and short rod adaptation deformation, so as to improve the safety and durability of the boom. The structure and construction technology of the derrick system are introduced.

Abstract:With the development of domestic prestressing technology, the post-tensioned ring anchor prestressing technology has gradually become a key technology in the construction of water conservancy tunnel projects in China. This paper mainly introduces the application of post-tensioning ring anchor prestressing construction technology in the South-to-North water transfer project through the yellow tunnel, summarizes the construction technology, operation steps and methods, quality control, etc., and provides reference and experience for the same type of ring anchor prestressing construction in the future.

Abstract:In this paper, the selection, composition and main design points of flexible temporary hoisting system in the suspension rod replacement of concrete-filled steel tube arch bridge are introduced, and the calculation and verification are carried out by finite element program. In addition, the related installation and construction technology of the temporary hoisting system are introduced, and the engineering practice proves that the flexible temporary hoisting system realizes the boom replacement safely and effectively. At the same time, the practice can provide reference for the replacement of similar bridge derrick and the design and construction of the same type temporary hoisting system.

Abstract:The new type of bridge with self-anchored cable-stayed coordination system has the characteristics of complex construction technology and difficult construction technology. In other words, it is necessary to ensure the balance of the forces on both sides of the suspension cable system and the cable-stayed system theoretically, and simultaneously monitor and dynamically adjust the construction scheme during construction. Another difficult problem is to control the installation position of the unconstrained space loose cable sleeve in the empty cable state and the offset position in the bridge state. This paper introduces the selection of the construction scheme and the concrete construction method of the superstructure of Nanping Cross-River Bridge, and provides reference for the construction of similar self-anchored cable-stayed cooperative system in the future.