A Test Study And Theoretical Analysis Of Vertical Belly Poles External Prestress Cable Structures

This paper proposes vertical belly poles external prestress cable structures reinforced technology is based on the traditional externally prestressed reinforcement technology based on an improved, but also the needs of engineering technology and engineering application, the initial length, the initial shape, the number of flank rod, the layout and structure, prestressed increment of deformation and the design problems need a theoretical guidance. To solve these problems, the subject of the reinforcement technique and calculation method of the reinforcement mechanism are analyzed, and the method for the promotion offer theoretical basis.The theoretical analysis of vertical belly poles external prestress cable structures,Based on the basic assumption of the change of te cable length, the expression of end forces and curve equation of the cable was obtained through the theoretical analysis of the cable element with uniform distribution load under the cable curve. And through the analysis of the relations between deformation, tension force and the load, the increment relation were obtained between the mid-span deflection, cable length and the load.The analysis shows:The maximum force of the cable located at the end of the anchor end; Under the conditions of giving the initial mid-span deflection, the cable length increment and the load increment were obtained by means of the mid-span deflection increment; The accuracy of the results is related to the magnitude of load-steps (the smaller load-steps is, the higher the accuracy is).In this paper, the experimental research part,7 Unit Tests with ordinary spring were taken to simulate the prestressed cable. Vertical load was imposed on the cable, according to the variation of vertical pole members, load-steps and height span ratio. The deformation rule of the cable was studied by testing the characteristic values of cable, such as cable length, the maximum cable sag value, the maximum tension value.The results show that (other conditions are equal):1) The larger the number of web member is, the more close the test result is to the theoretical analysis test;2) The smaller height span ratio is, the more accurate the calculation results is;3) The bigger height span is, the smaller the maximum tension value of cable is.The results can provide theoretical guide to the engineering.The txte provides references for reinforceing simply supported beam by external pre-stress reinforced technology of the vertical belly poles structure and the results can provide theoretical guide to the engineering.