Experimental study on seismic performance of thin-walled steel-straw board composite walls with built-in steel plate

Based on the original cold-formed thin-walled steel (CFS)-straw board composite wall, CFS-paper straw board-steel plate composite wall is proposed as a new type of composite wall. To examine the seismic performance of this type of wall, cyclic loading tests were conducted on seven wall specimens to investigate their hysteresis curves, skeleton curves, shear capacity, displacement, lateral stiffness, ductility, and energy dissipation coefficient. The key parameters of the specimens were as follows: with or without a steel plate, built-in/external steel plate, steel plate thickness, and single-sided or double-sided layout of steel plates. Experimental results show that the addi-tion of steel plates can improve the shear capacity and lateral stiffness of composite wall. Walls with steel plates of the same thickness placed on the inside have higher shear capacity, lateral stiffness, ductility, and energy dissipation performance than those placed on the outside. The shear capacity of a composite wall with double-sided steel plates is higher than that of a wall with single-sided steel plates. Increasing the steel plate thickness can improve the bearing capacity and lateral stiffness; however, the increase in shear capacity does not have a linear relationship with thickness. Finite element analyses were performed on the specimens to investigate the influence of other factors on the shear capacity of composite walls. Finally, the shear force flow calculation method was used to derive the shear bearing capacity of composite walls. The results of the shear capacity calculation formula derived based on the failure of the self-tapping screw connection compared with experimental values were found to be accurate.

Automated summary

The seismic performance of the cold-formed thin-walled steel-straw board composite wall was investigated through cyclic loading tests. The addition of steel plates improved the shear capacity and lateral stiffness of the composite wall. Walls with internally placed steel plates showed better performance than those with externally placed steel plates. Double-sided steel plates resulted in higher shear capacity compared to single-sided steel plates, and increasing the steel plate thickness improved the bearing capacity and lateral stiffness.