Abstract:Cable hoisting crane is a special equipment for hoisting the main beam of long span suspension bridge. The structure of full hydraulic walking cable crane is mainly composed of main truss beam, walking mechanism, power system, hydraulic system, control system and lifting system. In the process of being applied to the actual bridge, it relies on the main cable of the suspension bridge as the support to carry out the displacement walking and the fixation lifting. Before it is used in practical engineering, cable-borne crane should carry out type test, which includes static load test and walking test simulating real bridge hoisting condition. Two LZDJ5000T fully hydraulic walking cable hoist were developed for the main beam hoisting of Aizhai Bridge in Hunan Province. In order to carry out type test, a test device was designed for supporting and loading. The stress and mid-span deflection at the key point of the key section were measured during loading. The test results show that the displacement and deformation values of static load test are in good agreement with the theoretical values, and the performance of the loading system is good, the movement is accurate in walking test, and the performance of the whole machine is good.

Abstract:This paper introduces the system composition of the deck crane of Ningbo Daxie No. 2 Bridge. In the design process of the deck crane, ANSYS finite element software is used to simulate and analyze the loading condition of the steel truss in the process of the deck crane. The analysis results show that the stress, deformation and stability of the steel truss of the bridge floor crane meet the requirements of the relevant specifications. The results show that ANSYS finite element analysis can simply and quickly calculate the stress state of the bridge deck crane, which is conducive to checking the stability and safety of the structure, and optimizing the structure design, which has important significance for guiding the practical project.

Abstract:The anchorage system can effectively improve the safety and durability of prestressed concrete structures, and has the advantage of non-destructive testing. The portable LCR bridge meter is used to measure the resistance value between them. The resistance value can reflect the degree of corrosion of prestressed tendons, so that it can be well monitored Measured the working condition of the prestressed tendons. Through the application in the actual project 30mT beam, the problems that need to be considered in the project application are obtained, and some solutions are put forward to make a beneficial attempt for the next step.

Abstract:This paper introduces a kind of small and medium-sized pedestal structure used for prestressing double-T plate prefabrication by tensioning method, and the related checking calculation methods of strength, stiffness and stability. Finally, it focuses on the related issues that need attention in pedestal construction.

Abstract:The Huxi Bridge in Liuzhou has caused some diseases due to long-term overload operation. In order to ensure the operation safety of the bridge, it is decided to replace the cable of the bridge. The replacement cable adopts parallel wire cable, and the supporting anchor is cold cast anchor. This paper mainly introduces the cable replacement construction technology and construction technology of Huxi Bridge.

Abstract:Liuzhou Shuangyong Bridge spans the Liujiang River. The main bridge is a three-span continuous steel box girder suspension bridge with a single main cable gravity anchorage suspension cable structure. The main bridge is constructed by means of the main cable erection and the box girder pushing synchronously, and the system conversion is realized by the derrick tension. The unique main bridge structure and novel construction procedures add highlights to the construction process of the bridge.

Abstract:This paper mainly introduces the maintenance and construction technology of the cable-stayed cable of Wuhan Baishazhou Bridge, analyzes the causes of the cable-stayed cable diseases, and adopts corresponding maintenance schemes according to different conditions of the cable-stayed cable diseases, hoping to provide reference for similar maintenance projects.

Abstract:Bridge health monitoring system is a new technology applied to bridge management and maintenance in recent years, which has important engineering value. Wireless vibrating wire sensor has the characteristics of strong anti-interference, high precision, long transmission distance, etc., and is widely used in the monitoring of dynamic physical quantities such as vibration and stress in mass concrete structures. This paper mainly discusses the structure of bridge wireless strain monitoring system and the working principle of wireless vibrating wire sensor, designs the vibration excitation circuit and frequency measurement circuit inside the vibrating wire sensor, as well as the wireless communication module, and gives the design of internal software and analyzes the characteristics of the wireless vibrating wire sensor. The wireless design greatly facilitates the use of vibrating string sensor. The practical application shows that the bridge wireless strain monitoring system based on sine sensor designed in this paper is stable, reliable in quality and fast and accurate in measurement data.

Abstract:It is an important measure to control the effective prestress accurately by measuring the friction loss of the anchor port and adjusting the tensile force according to the test results during the tensioning construction of the prestressed steel strand. It is of great significance to measure the frictional loss of anchor port accurately to ensure the accurate application of design tensile force. The common problems affecting the measurement of the friction loss of the anchor port are summarized and analyzed by combining many abnormal cases and experiences in the field measurement of friction loss.