Model Test On Lateral Bearing Capacity Of Inclined Piles In Rock Slope

Landform and geological conditions in southwest China is changeable and complex,When the railway and the highway line cross the rivers,valleys or mountains,it is necessary to build bridges to connect the lines,which are always accompanied with piles.Presently,the main research direction of the pile foundation is the bearing pile in the horizontal foundation.There is nearly no systematic research on the lateral force mechanism of inclined pile foundation in rock slope.In this paper,the model test is taken as the research method;and the numerical simulation is used to analyze the results of the model tes.Some conclusions are obtained as follows:(1)Inclined pile foundation in rock slope under the condition of the transverse force,the bending moment distribution of overall trend is from the ground along the pile increasing first,then reducing and finally the nonlinear distribution decaying to zero again.when the pile in the depth of 14D?17D,the maximum bending moment distribution in the slope is among 6D?9D.With the increase of lateral load,bending moment value grows,which does not change its distribution law along pile shaft.(2)The influence of axial force of inclined pile foundation in rock slope on its lateral bearing capacity:The axial pressure of the pile is equivalent to the prestressing force,improving the lateral bending stiffness,thus improving the lateral bearing capacity.(3)The influence of rock slope with a sliding band on its lateral bearing capacity:The existence of the sliding band makes the pile moment under the same lateral load larger.As the sliding band causes the dielectric discontinuity of the rock 1,which reduces the stability of the slope,weakening the inclined pile's lateral bearing capacity.Therefore,consideration should be taken into the design of pile foundation in rock slope when faced with a sliding band.(4)The influence of the change of the lateral stiffness of the pile on its lateral bearing capacity:The larger the bending stiffness,the greater the bending moment value and the smaller lateral displacement of the surface is.The reverse is also true.As a result,Improving the flexural rigidity can effectively increase the lateral bearing capacity of pile foundation in rock slope.(5)The influence of the lateral thrust of the slope on its lateral bearing capacity:The distribution of the slope band thrust along the pile shaft is like parabola.The distribution of soil pressure in front of the pile above the sliding surface increases with a triangle distribution,while the soil resistance under the sliding surface is an inverted triangular distribution.