Shear lag behavior and parametric sensitivity analysis of steel–concrete composite structure with double-box

Abstract

Due to non-uniform distribution of structural deformation along its transverse width direction, shear lag behavior widely exists in composite structure with multi-box and leads to structural instability and destruction. To in-depth explore its mechanical mechanism, a type of steel–concrete composite structure with double-box (the DBSCCS model) is proposed, and its longitudinal warping shape functions are set up. Based on the minimum potential energy principle, governing differential equations of the DBSCCS model and its boundary conditions are deduced by means of the variational method. And then, its strain functions and shear lag coefficients are also obtained under concentrated loading and symmetrical loading, respectively. What is more, experimental verification and its related parametric sensitivity analysis are launched based on deduced longitudinal strain functions and shear lag coefficients. Through this analysis, it shows that this method can be used to illustrate and predict shear lag characteristics for this type of the DBSCCS model. That further suggests that it provides a more reference value for engineering design and structure optimization in some extent for the composite structures.