Model Test Research On Lattice Beam Anchorage In Landslide Reinforcement

Lattice beam anchorage has been one of the major landslide reinforcement measures becauseof its light structure, beautiful shape, excellent anti-seismic performance and mobilization ofslope’s own stability. Furthermore, with the advantage of high-speed construction andcontrolling, lattice beam anchorage is widely used in the world. However, owing to it’s shortapplication time and complex reinforcing mechanism, we know less about its anti-slidingmechanism. The theoretical research on lattice beam anchorage has been lagging behind inthe engineering application. And the design method has not reach standardization andregulation.Based on field survey of project case, large scale physical model tests are carried out forresearches on lattice beam anchorage. The stress status of lattice beam anchorage was studiedin this paper by resistance strain gauge, anchor tension cell, earth pressure cell and so on. Inorder to prove the results of the physical model test, a finite element model was establishedwith software ANSYS. With the results of both the model test and numerical simulation, theforce deformation, working mechanism and failure mode of the lattice beam anchorage areanalyzed, and one simple mechanical model and a design method of lattice beam anchoragewere put forward.The result of this paper will provide a theoretical basis for the design andpopularizing of lattice beam anchorage. The conclusions of this study are as follows：(1)There are two kinds of failure modes of anchor in lattice beam anchorage, one is slippedout and the other is shear failure, the failure of lattice beam are bending cracking and fractureat the joints.(2)For full grouting anchor, the anchoring force loads to the lattice beam are slightly and thefoundation pressure distributes as triangle; for partly grouting anchor, the anchoring forceloads to the lattice beam are big and the foundation pressure distributes as V-sharp.(3)For full grouting anchored lattice beam, the anchor play a key role in anti-sliding and thelattice beam is used for slope surface protection, this kind of lattice beam anchorage issuitable for controlling of the landslide with good global stability but easy to creep at the footof slope and slope protection; for partly grouting anchored lattice beam, the tensile andcompressive effect of lattice beam and anchor improved the stability of landslide, and thiskind of lattice beam anchorage is suitable for controlling of large landslide reinforcement.(4)If the anchor is full grouting, constructional reinforcements are enough for the lattice beam;for partly grouting anchored lattice beam, a design method for lattice beam anchorage based on soil arch theory was put forward. In this method, the rational anchorage spacing was getconsidering aching effect, and then the reverse beam method with the foundation pressuredistributes as V-sharp was taken to compute the internal force of the lattice beam.