A Study on the Eccentric Loading of K Node of Steel Tube Tower

Abstract

Keywords: steel tube tower, negative eccentricity, bearing capacity Abstract. At present, in the steel tube tower, all the diagonal members' axial leads intersect on the main members' axial leads which would always cause the large size of node plate. The existing theoretical analysis shows that negative eccentricity of node connection can decrease the size of node plate, reduce the windward area and improve the bearing capacity of node plate. This project will calculate the influence of negative eccentricity on the bearing capacity of node plate of steel tube tower through testing and theory. The test and theoretical analysis shows that negative eccentricity is extremely unfavorable for the overall instability of members. When the slenderness ratio is large, the negative eccentricity should be avoided, or checking calculation of bearing capacity should be carried out according to the compression-bending members, in order to avoid the overall instability failure of members, and the local buckling not occurring on the testing members, through the finite element and testing phenomenon, it is found that force-deflection curve dropped very fast at the later loading stage, which means the member bearing capacity sharply decreased and then lost stability; through the test research, it is found that the larger the negative eccentricity is, the lower the bearing capacity of main tube would be, for instance, the negative eccentricity of 3D/8 is 50% larger than D/4, but its main tube bearing capacity is about 40% lower. Therefore, the negative eccentricity is unfavorable for the overall instability bearing capacity of main tube.