Creep Behavior Of Thin-Walled Steel Tube/Bamboo-Plywood Composite Column With Binding Bars

Bamboo is a fast-growing,high-yield,high-strength,low-energy-consumption biologic material,which is widely used in engineering structures.However,limited by the structural shape and anisotropic characteristics,the original bamboo can't be applied in batches industrialization,Reasonable combination of steel and bamboo can bring their advantages into full play and have broad application prospects.On the basis of the research on the existing compressive properties,the creep behavior and the post creep bearing capacity of a new type of thin-walled steel tube/bamboo-plywood composite column with binding bars(SBCCB)are further tested.Four specimens of SBCCB with the slenderness ratio of 40?70 were each subjected to an axial compressive creep test and a subsequent axial compression test to examine their axial compressive creep behavior and post-creep compressive failure modes as well as to analyze the effects of long-term loading on the ultimate axial compression-bearing capacity of SBCCB.The equation of creep of the Burgers mechanical model was selected to carry out the nonlinear fitting of the creep experimental date.And the predicted creep model was established.The results show that:at the same moment of the creep test,the axial compressive creep strain decreased with the increasing slenderness ratio and increased with the increasing axial compressive stress.The curves of axial compressive creep strain-time for specimens generally exhibited a similar tendency,At the end of the creep test,all SBCCB are in the steady-state stage of creep development,and no obvious failure characteristics are observed.Temperature and humidity variation had significant effect on the creep behavior.The long-term loading significantly affected the axial compressive load bearing capacity as well as the axial and lateral deformability of the SBCCB.To be specific,There has a 8.1%?11.5%decline of the ultimate axial compressive load bearing capacity,and about a 15%decline in the maximum axial and lateral deformation capacity.Burgers mechanic model can well predict the creep strain development under different slenderness ratio and stress level,It is suitable for describing the creep behavior of SBCCB.