Study On Analysis Method Of Gate-Type Anti-Slide Piles In Engineered Slope Or Large-Scale Landslide Control

The gate-type anti-slide piles structure is a new type of retaining structures.The pre-and post reinforced concrete piles which are seted up to the appropriate place of the landslide site are banded together by the crossbeam,which form a space frame structure. The gate-type anti-slide piles structure have some advantages such as larger rigidity, less displacement in the top of the piles and large anti-force, beneficial for anchored part which have a weaker geological areas. At the same time relative to the single pile, there are many shortages such as complex structure, short history, immature theory of computation, force mechanism is not clear. So there are still many issues worthy of further research, such as the distribution of landslide thrust in the structure, reasonable structure form, reasonable method for designing and calculating. The light of these shortcomings, the main contents of this paper is as follows:(1) Summary of laboratory model experiments,results of the field tests and results of the FEM software, the distribution of the landslide pressure is as follows:the thrust form of the rear pile can instead by rectangular or trapezoidal, the thrust form of the front pile can instead by trapezoidal, the resistance form of the pre-and post pile can instead by triangular.(2) Against characteristics of the gate-type anti-slide piles, we suggest the calculating method for the landslide thrust of the structure.The force of the rear pile is calculated by transfer coefficient methods. The force of the front piles is calculated not only by the active earth pressure, but also the additional one due to the press of the soils between the double piles.(3) The author establishes the reasonable numerical model with the application of PLAXIS software and analyzes the regularity of how such factors as space between rows of gate-type anti-slide piles structure, stiffness of the crossbeam and modulus of soil between rows exert their influences on the bearing capacity of structure. Then the acceptable space between rows under the structure of 3B-4B is proposed(B stands for the cross-section width of Piles). And a conclusion is drawn that increasing the stiffness of the crossbeam and modulus of soil between rows appropriately can make the force of the structure more reasonable.(4) It is proposed a method for designing and calculating by using the theory of the structural mechanics and the elastic mechanics,and checking it by practical project.(5) Under the same conditions, analyzing the single pile and the gate-type anti-slide piles structure,we found the gate-type anti-slide piles structure have unique advantages in controling displacement and bending moment.