Study on overall stability and bearing capacity of thin-walled cold-formed steel built-up specimens
The thin-walled cold-formed steel specimens are spliced along the axial length,and the bearing capacity of the composite section specimen is better than that of the single limb specimen.In order to study the influence of built-up effect to the overall stability of double-limb composite section specimens,the bearing capacities of 158 double-limb composite sections tested specimens were calculated and evaluated.The following assumptions were used in the calculation of bearing capacity:the double-limb specimens is regarded as two independent members without the built-up effect;the composite section is simplified by equivalent section substitution and spring constraint substitution respectively with the built-up effect.After comparing the calculated values of bearing capacity with the experimental results,it is found that the calculated values without built-up effect have a large coefficient of variation and are not reliable.The calculation accuracy and reliability of the equivalent section substitution and spring constraint substitution method depend on the selection of specific section parameters,and the applicability to different types of sections is not good.Therefore,based on the direct strength method,a modified formula for the overall buckling and local buckling strength curves was proposed for the built-up effect of the double-limb composite section specimens.The calculated bearing capacity has high accuracy and reliability,and the applicability is good.
NETL
NSTL
万方数据
