Research on Interface Slip Characteristics of Heritage Composite Timber Columns under Inclined Deformation

In order to study the mechanical performance and friction slip mechanism of the interface of a composite timber column under inclined deformation, the unilateral contact mechanical model of an ancient composite timber column under inclined deformation is proposed in this paper. According to the limit of the inclination angle of slip point and the limit of the inclination angle of slip surface, the failure modes of the combination’s interface can be divided into three stages: the fully sticky stage, the partially sticky stage and the sliding stage. The theoretical results of the sliding displacement and shear stiffness of the combination’s interface under the effect of iron hoops were obtained by using the elastic mechanics method. Based on the shear sliding test of a composite timber column’s interface under the effect of iron hoops, the influences of different parameters on the shear sliding performance of the combination’s interface were investigated. The test results show that the number and the spacing of the iron hoops and the inclination angle of the interface are important factors affecting the shear strength of the combination’s interface. The shear strength of the interface increased with the increase in the number of iron hoops and the inclination angle of the interface. Since hoop spacing that is too large or too small cannot effectively improve the shear capacity of the interface, there is an optimal value for the hoop spacing.