Calculation And Deformation Analysis Of The Pile-Anchor Supporting Structure

Some deep foundation pit taken as the background, design and calculation is done for the Pile-Anchor supporting structure, then combined with numerical analysis, deformation characteristics of the Pile-Anchor supporting structure is researched.Continuous beams method and"M"method are founded to research the design and calculation for the Pile-Anchor supporting structure, which are complemented each other, overcoming each shortcoming. Engineering monitoring shows that the calculation in the paper can be implemented.The analysis model of nonlinear finite element for the Pile-Anchor supporting structure is founded. Distribution discipline for the horizontal displacement beyond the foundation, soil surface subsidence beyond the foundation and subsidence along with the depth is analyzed. Conclusion is that:(1) Side shifter of the supporting piles is not on the excavation top, but on the middle of the upper;(2) Within the range of the buried depth of the supporting structure, soil displacement of the foundation pit lateral is small; when below, there is the tendency of soil beyond the foundation lateral to the inside;(3) The earth's surface settlement of the foundation lateral shows parabola, and the maximum is from1.5 times to twice excavation depth in the distance of the supporting structure;(4)Soil settlement of the foundation lateral is different with different depth. When within the range of the buried depth of the supporting structure, the soil settlement is bigger, and the settlement increases with the soil depth; when below the embedded depth, the soil settlement is tiny.(5)In the first two steps of excavation, foundation uplift height is relatively small and uplift curve is obvious. With the further excavation, the height of uplift increases rapidly; the minimum uplift is in the supporting structure, the bigger the further away from the supporting pile, and the maximum is in the middle of the foundation about twice depth of the excavation.Usually geometric parameters of the influence to the pile is including pile embedded depth and pile diameter, the slope pile is accounted for a large proportion of the total cost. So it is important to research the two parameters. The influence of supporting pile embedded depth, pile diameter, the anchor length and so on to the deformation of supporting structure is researched, the conclusions are following:(1) The more is the embedded depth, the smaller is the deformation of the supporting structure. When the embedded depth is changing in the shallow, the influence is more. From the figure, when the embedded depth is up to 9m, the maximum displacement of the supporting structure is leveling off.(2) The stiffness of support structure changes with the pile diameter. With the increase of the pile diameter, the deformation of the supporting structure is reduced, when the pile diameter is up to 2.4m, which is 3 times of the diameter of the project, the influence to the support structure is samll.