MODEL TEST STUDY ON CONTACT PRESSURE OF PRESTRESSED ANCHOR LATTICE BEAM

This paper examines the deficiency in research about the contact pressure of current lattice beam internal force calculation methods. It carries out the study of a 1:2 large-scale physical model test and analyzes the distribution of foundation counterforce. The result indicates that the distribution of beam contact pressure is not uniform. For horizontal beam, the foundation counterforce near node is stronger than that in the middle segment of the beam. For vertical beam, the reaction appears to be a trapezoidal distribution with top weaker and this trend is more obvious with the loading. The contact pressure of each horizontal beam is equal in prestressing stage while it appears a distribution as the vertical beam in landslide developing stage. There is a certain proportion relationship between the span reaction of vertical beams and that of the corresponding horizontal beam span. The coefficient of proportionality is between 0.4 and 0.6. The reaction force is all different among the angle node, the edge node and the center node. It is the strongest at the angle node. The edge node comes the second. The center node weakest. Their proportions are 2.15:1.15:1.00.