Studies On In-plane Strength Design Method Of Sinusoidal Corrugated Web Arches And Steel Tubular Vierendeel Truss Arches

Steel arches have been widely used in different kinds of structures,from roofs to bridges.Solid-web section arches including I section and box section and truss arches with diagonal tubes are common types for practice.This paper investigates two new types of steel arches,sinusoidal corrugated web arch and tubular vierendeel truss arch,theoretically,numerically and experimentally in their in-plane elastic buckling and elastic-plastic carrying capacity.Considering the influence of the sectional shear force on failure mode,the design method of in-plane strength of these two arches are proposed separately.Compared with common I-section arches,flat web is replaced by sinusoidal corrugated web in steel arches with sinusoidal corrugated web,which leads to different mechanical properties.This paper firstly derives the sectional shear modulus of the arch with sinusoidal corrugated web,analyzes the influence of shear deformation on in-plane elastic buckling and accurately obtains the in-plane elastic buckling load under pure compression.Then,based on the design method of columns under axial compression,the normalized slenderness and reduction factor of strength are introduced to obtain the design curve of arches under uniform compression according to the nonlinear FE results.Circular arches with sinusoidal corrugated web subjected to other load conditions are also studied.Based on numerical results of FE models,the interaction design equation is proposed for the global in-plane strength of circular arches with sinusoidal corrugated web under different load types.Besides,design equation for shear strength of the arch is proposed based on the shear failure mode and mechanism.Compared to conventional truss arches,the vierendeel truss arch is an arch only with transverse tubes without diagonal tubes,which leads to a different transfer path of the shear force.Similar to arches with sinusoidal corrugated web,the sectional shear modulus,in-plane elastic buckling load,design curve under pure compression and interaction design equation are all obtained through theoretical and numerical method.The shear failure mode varies due to the change of the ratio between stiffness of transverse tubes and stiffness of the chord.Different local failure modes caused by shear force are thoroughly investigated,and one kind of local failure modes is acceptable comprehensively considering carrying capacity,stiffness and deformation.And the corresponding strength design equations are proposed.Three specimens of circular steel pin-ended arches with sinusoidal corrugated web are tested to investigate the effect of loading types,section parameters,and in-plane geometric imperfection of arches on the in-plane elastic-plastic strength of the arches.The results of the tests can verify the in-plane elastic-plastic strength design method and the correctness of FE models of steel arches with sinusoidal corrugated web.