Experimental Study On Shear Behavior Of Machine Sawing Stone Masonry Joints With Shear Connector

In the modern stone masonry structure,there exist negative effect on the shear strength and seismic performance of masonry joints using machine sawing stone due to relatively smooth on the stone interface.Therefore,it is necessary to processing the stone interface to improve the shear performance resistance of the stone masonry joints.In this paper,shear connector and slotting on the sawing stone are adopted to improve the interface behavior of joints and the experimental research on the shear resistance and seismic performance of machine sawing stone masonry joints is carried out.Shear performance tests were carried out on 23 sawing stone masonry joints specimens,including 7 specimens with only sawing interface and 16 specimens with shear connector and slotting on the sawing interface.The test parameters include the type of joint interface,vertical compressive stress and mortar type(common high-strength mortar and polymer mortar).The test results shown that:(1)the failure process of machine sawing stone masonry joints shows obvious brittle failure characteristics,and there exist a friction-slip stage after the strength of masonry joints descending from its maximum point;(2)the shear strength of the masonry joints increases with the mortar strength and it increases approximately linearly;(3)shear connector on the interface can effectively improve the shear capacity of the joint,and with the increase of the number of shear connector,the shear capacity increases approximately linearly;(4)increase the vertical compression can effectively improve the shear strength of the masonry joints;(5)both increase of the compressive stress and setting up shear connector can increase the residual shear strength of the sliding stage to a certain extent;(6)the influence of interface slotting on the shear resistance and residual strength is very limited.Based on the statistical analysis of the test results,the calculation formula for the shear strength of sawing stone masonry joints with shear connector is proposed.Cyclic loading tests on 7 sawing stone masonry joints were carried out,to study the influence of interface form and mortar strength on the seismic performance of sawing stone masonry joints.The test results shown that:(1)Before reaching the maximum load,the hysteresis curve is basically linear;after the maximum load,the shear capacity drops suddenly,showing an obvious brittle failure characteristics;the residual capacity on the friction-slip stage tends to be stable and the shape of the hysteresis loop is approximately rectangular and basically remains stable during subsequent cyclic loading.(2)Test results showed no significant difference in the skeleton curve of cycle loading and monotonous loading.