Punching failure test study on raft foundation under column load

The punching failure of corner columns and border columns under vertical concentrated columns load is studied through large-scale model tests in the laboratory.On the basis of crude soil,two identical raft foundations are tested under different loads.Different punching failure values of the corner columns,border columns are obtained under the vertical concentrated column load,and these values are compared with the code’s values.The study shows the control failure section of the raft foundation is the punching failure section,and that the increase of the rigidity of foundation and upper structure and the reduction of the differential settlement of the raft foundation can greatly improve its carrying capacity and enhance the degree of safety in designing raft foundation.