Analysis And Research On Mechanical Properties Of Long-span Cable Hoisting System

With the large-scale construction of bridges in our country,there are a large number of segmental hoisting construction operations.Cable hoisting system has the unique advantages of strong adaptability to various environments and large hoisting capacity,so it is more and more widely used in the field of bridge construction.The cable hoisting system is developing towards long span and large hoisting capacity,which puts forward higher requirements for the accuracy of the calculation theory.In order to accurately consider the influence of slip on the internal force and shape of the load-bearing cable,the frozen-heated method is introduced into the calculation of the load-bearing cable slip of the cable hoisting system for the first time,based on the cable hoisting system of Meixi River Bridge on Zheng-Wan Railway,which is the largest span ballastles track high-speed railway arch bridge.this paper mainly researches the following aspects:1.The relationship between the shape of load-bearing cable and internal force of cable hoisting system is analyzed.According to different assumptions,parabolic equation and catenary equation are respectively deduced,which provides a theoretical basis for subsequent research.The relevant principles and calculation steps of frozen-heated method and slip stiffness method are described,and their difference is compared and researched according to the calculation results of the calculation examples;2.Based on the project,the relevant parameters of the load-bearing cable are calculated respectively according to the design methods of the load-bearing cable of the cable hoisting system such as classical analytic method and finite element method,the calculation results are compared and analyzed,and the relevant suggestions for the design of the load-bearing cable of the long-span cable hoisting system are put forward;3.This paper analyzes the causes of abnormal lateral deviation of the pylon in this project,researches the static performance and stability of the pylon structure of special cable hoisting system with offset anchorage.The analysis shows that there is a larger lateral deflection for unbalanced lateral tension transmitted by the cable,when the cable hoisting system is loaded on one side;4.The load test of the project is researched and the measured and theoretical values related to the load test are compared and analyzed.The overall mechanical performance of cable hoisting system is verified to be great,and the safety of the hoisting construction process is ensured.The accuracy of the frozen-heated method introduced in this paper is verified.