Study on fatigue performance evaluation and reinforcement technology of thin web steel crane beam with right angle mutation support
The bending stress generated by the out of plane deformation of the web plate of a thin web steel crane beam with a thin web right angle mutation support under crane load significantly reduces the fatigue resistance of the crane beam web plate.In practical engineering,it has been found that the thin web right angle mutation support thin web steel crane beam generates fatigue cracks vertically on the web plate at the insertion position of the plate end,with a maximum crack length of 300 mm.Continuing to crack will seriously threaten the structure and production safety of the factory building.By measuring the dynamic stress,equivalent coefficient of underload effect,and out of plane dynamic deformation of a cracked steel thin web crane beam with a right angle mutation support,it was found that the frequency of crane operation and the radian of the insert plate are the key factors affecting the fatigue strength of the web at the insertion plate end position.Using the finite element method and fatigue crack growth analysis technology,the quasi-static fatigue crack growth simulation was carried out on the web of the steel crane beam inserted into the end of the plate on the right angle mutation support crane beam,and the relationship curve between the crack length and the Stress intensity factor was obtained.Two reinforcement methods,steel plate high-strength bolt reinforcement and'shell plate'welding reinforcement,were proposed for thin web right angle mutation support thin web steel crane beams,and the effectiveness of the two reinforcement methods was compared and analyzed.The research results of this article can provide scientific basis for the fatigue performance evaluation and fatigue reinforcement work of thin web crane beams with right angle mutation supports in practical engineering,and it has been proven that both steel plate high-strength bolt reinforcement and'shell plate'welding reinforcement can effectively reduce the stress intensity factor at the crack tip and improve the fatigue strength of the right angle sudden change support steel crane beam.
国家科技期刊平台
NSTL
万方数据
维普
