Research On Stable Bearing Capacity Of High Strength Steel

With the rapid development of electric power industry in China in recent years,large capacity, long distance, high voltage transmission lines are more and more withload increasing, Because of its smaller wind resistance effect, good technicalperformance and beautiful appearance, steel pipe tower is developing rapidly in largecapacity, multiple circuit transmission lines. With the thorough study of steel pipestructure and application of high strength steel, the development prospects of highstrength steel structure is very broad. At present, high strength steel pipe in transmissiontowers is in the application of less in our country, still no relevant technical regulationon the design of it. The tower structure calculation model is space truss structure, andcomponent is designed according to the stability of pull bar and the pressure bar. In theuse of high strength steel pipe, pressure bar stability will be the most importantinfluencing factor of structure bearing capacity. To solve this problem, this paper carriesout the following aspects of the work.(1) Theoretical analysis: carries out theory analysis of bearing capacity calculationof Q420, Q460high strength steel pipe, using inverse unit length method to propose thetheoretical calculation method. This paper also needs to use FORTRAN95languageprogram to calculate column curve of axial compression members of Q420, Q460highstrength steel pipe.(2) Experimental research: experimental research is one of the most importantmethods on high-strength steel pipe stability. This paper carries out experimentalresearch of Q420, Q460steel pipes on different slenderness ratio of273x6356x10426x8on dimensions, and gets the failure modes and ultimate carrying capacity ofdifferent components.(3)Finite element analysis: carries out finite element analysis on a number ofdifferent specifications of273x6356x10426x8high strength steel pipe of Q420andQ460. Considering initial flaws of the pressure bar, sets up a model and analyzes itsstability. This paper also studies the influence of slenderness ratio, diameter thicknessratio on the ultimate bearing capacity of the steel pipe.(4) Suitable computational methods: takes a research on bearing capacity calc-ulation method of high strength steel members under axial compression. Integrated theabove study results, this paper verifies the current specification for high strength steel column curves of applicability, and puts forward the reasonable construction method,providing reference for the actual project.