Study On The Overall Stability Of H-shaped Steel Beams With Thin-walled Rectangular Corrugated Webs

Based on the characteristics and limitations of corrugated web and cold-formed thin-walled steel structures,this paper presents a new structure:thin-walled corrugated web H-beam by combining《high-frequency welded thin-walled H-shaped steels》,intended to improve the overall stability of thin-walled H-beam.In order to promote more ripples in China’s comprehensive promotion,so the ripple is set to rectangular waveform.The main contents and conclusions of this paper are as follows:1、This paper presents a new structure of the cross-section geometry of the primary basis for a detailed elaboration,and then the new component of the cross section was designed,including web height,web thickness,amplitude,wavelength,flange width,flange thickness and other parameters.The author of the proposed new components for a utility model patents,accepted the patent number 201620571726.5.2、This paper deduces the calculation formula of calculating the cross-section characteristic of the new member,and selects a set of cross-section of the ordinary welded thin-walled H-beam in the《high-frequency welded thin-walled H-shaped steel structure》,and uses the simplified formula the cross section characteristics of the new members are calculated and compared with those under the same conditions.It is found that the Iy and Wy of the new members are larger than those of the ordinary welded thin-walled H-beam beams,which indicates that the lateral bending ability of the new members is greater than that of the flat belts,the stability of the components is improved,and the lateral bending stability of the members is improved.Finally,according to the relevant specification,a series of cross-section models are constructed for the new members;3、In this paper,ABAQUS finite element software is used to model the proposed components.Regardless of the initial defects of the components,the study is limited to the elastic buckling range,and the boundary conditions and loads are set according to the geometrical parameters of the corresponding elements form.The relationship between the geometric dimensions and the critical buckling load of the new members is obtained by changing the geometrical parameters of the components.The results show that:(1)The thicker the thickness of the web the greater the critical buckling load value when the component is unstable,the increase of the web thickness can improve the overall stability of the component;the higher the height of the web,the greater the critical buckling load value it is shown that the increase of the height of the web has a positive effect on the overall stability of the component.The change of the amplitude has little effect on the overall stability of the component.The longer the wavelength is,the smaller the critical buckling load is,the overall stability of the negative correlation between the negative trend;(2)The increase of the flange width increases the critical buckling load of the component to a certain value and then decreases,indicating that increasing the flange width can improve the buckling load of the component,but reaching a certain value will reduce the buckling of the component The greater the critical buckling load value when the component is unstable,the greater the thickness of the flange can increase the overall stability of the component to a certain extent.4、To further analyze the characteristics of this paper projecting rectangular waveform,in comparison under the same conditions and the triangular wave sinusoidal waveform of each geometric parameters influence of its critical buckling load value with the following results:(1)Thin-walled rectangular corrugated web H-beam within the span range of 5m～6m overall stability has obvious advantages;(2)The critical buckling load value of the thin-walled rectangular corrugated web H-beam girder in the case of the same web thickness is higher than that of the triangular waveform and sinusoidal waveform,and the critical buckling load is increased by about 8%to 9%;(3)The critical buckling load value of the thin-walled rectangular corrugated web H-beam girder is much higher than that of the triangular waveform and sinusoidal waveform when the web height is the same,and this gap is more obvious when the web height is more than 800mm Buckling load value increased by about 15%to 24%;(4)Compared with triangular and sinusoidal ripples,the wavelength has no obvious effect on the critical buckling load of thin-walled rectangular corrugated web H-beam girder.Compared with sinusoidal waveform,the critical wavelength The buckling load value is increased by about 6%～17%,and the thin-walled corrugated web H-beam will have better overall stability than the triangular and sinusoidal web H-shaped steel with the increasing wavelength under the same conditions beam;(5)Under the same condition,the critical buckling load value of the rectangular wave component is larger than that of the sinusoidal and triangular waveform with the increase of the flange width,and the critical buckling load value is increased by about 10%.(6)When designed,if desired,in the case of wide-flange may prefer a thin-walled rectangular corrugated web H steel beam,and suitably increasing the thickness of the flange,can further improve the overall stability of the member;In addition to the amplitude of this parameter,the critical buckling load of the H-beam girder of the thin-walled rectangular corrugated web is larger than that of the thin-walled rectangular corrugated web H-beam members in the process of the same parameter change.The critical buckling load values are significantly higher than the triangular and sinusoidal ripples.This is an important conclusion of this paper.