A push-out test on partially encased composite column with different positions of shear studs

Abstract

Push-out tests were designed and carried out on partially encased composite columns (PECC) with different positions of shear studs. A unilateral push-out method was used to investigate the situation when the two sides of the web were arranged differently. The effect of the stud height, stud spacing, stud diameter, stud position, and concrete strength on the shear performance of PECC was evaluated. Test results illustrated that the position of studs is a considerable parameter for the shear performance; Compared with the concrete strength, the diameter of studs had a significant influence on the shear performance of PECC; The shear stiffness and strength decreased with the stud spacing decreased. A calculation model of the stud shear stiffness with clear physical meaning in PECC was proposed. The proposed model indicated that the shear stiffness was not only supported by the concrete elastic modulus and the stud diameter but also affected by the stud height. The calculated results were in line with the experimental results. In addition, a calculation model of the shear strength of PECC was also proposed. The model considered the influence of friction and welded collar. The analytical method exhibited in this paper could be employed to forecast the shear strength of PECC precisely.