Research On Resistance To Bending And Shearing Of Core Filled PHC Pipe Pile

Prestressed concrete pipe piles because of its high strength,high vertical bearing capacity,good adaptability to various geological conditions,quality being easily ensured,convenient construction and so on,have been widely used in our country project.However,when the prestressed concrete pipe pile is under horizontal load,the bending and shearing capacity of the pile is poor,which restrict its application in many engineering.In engineering,the core filling method is often used to enhance the bending resistance and shear resistance of prestressed pipe pile,but at the present stage,the related design standards of prestressed concrete pipe pile did not involve the influence of core filling on the bending and shearing capacity of pipe pile and the corresponding design and calculation method.In order to fill the shortage of the design method of PHC pipe pile in the standard of prestressed pipe pile in the present stage,Through the plain concrete filling core and non filled core of PHC pipe pile indoor flexural and shear bearing capacity test,theory analysis and numerical simulation method,systematically studied plain concrete filling core of PHC tube pile bending,shear bearing capacity,the main research contents and conclusions are as follows:1 Through the contrast test of flexural and shear capacity of concrete filled core and non core filled PHC pipe pile,the influence of the concrete filled core on the bending and shear capacity of PHC pipe pile is studied systematically.The test results show that: compared with the hollow core PHC pipe pile,the core filled PHC pipe pile’s bending and shear capacity is greatly improved.The cracking moment of the core filled PHC pipe pile is increased by 24%,the ultimate moment is increased by 32%,and the crack resistance shear strength is increased by 16%,and the shear strength is increased by 5.6%.2 Based on the theory of mechanics and superposition principle,the calculation formula of bending and shearing capacity of PHC pipe pile with concrete filled core is derived.Comparing the calculated results with the experimental results,the results agree well with the experimental results,which proves the rationality of the formula.3 By using Ansys finite element analysis software,analyzed the effect of concrete filled core on the flexural and shear capacity of PHC pipe pile.The simulation results show that by concrete strength grade of C30 plain concrete filled the core,compared with the hollow core PHC pipe pile,the core filled PHC pipe pile’s ultimate bending moment increased by 29.8%,ultimate shear force increased by 6.1%;The concrete strength grade of C60 plain concrete when core is filled,compared with the hollow core PHC pipe pile,the core filled PHC pipe pile’s ultimate bending moment increased by 58% and ultimate shear force increased by 25.9%.So fill the higher the strength grade of concrete core,PHC pipe pile bending,shear bearing capacity increases more;by different strength concrete filling core of PHC pipe pile bearing capacity curve showed that,when filling core concrete strength grade reaches a certain value,core filled PHC pipe pile’s bendingl,shearing capacity enhancement effect to reduce.