SETTLEMENT ANALYSIS OF SINGLE, STATIC AXIALLY LOADED STRUCTURAL PILE IN CLAY SOIL ON A NATURAL AND LIME TREATED CONDITION

Abstract

Piles are deep foundations, necessary when the bearing capacity of shallow foundations is not enough to ensure the support of the superstructure. When the underground soils are very weak the structure undergoes high settlement and that leads to high repairing cost. Therefore the purpose of this thesis is to analyze the settlement of single piles under axially loading of clayey soil with a consideration of lime treated and untreated conditions. Comparison of the two outcomes is as well the objective of this thesis. The proposed activity in order to intend the purposes includes a literary review on settlement analysis, soil treatment method and the analysis part computed by axisymmetric elastic modelling so called Plaxis are used. The finite element-based program of Linear Elastic (LE) model used for the pile since it is used to model stiff objects based on Hookes’s Law of isotropic elasticity. The analyzed piles are cylindrical and isolated and the loading is performed axially. These conditions allow for the use of symmetry; thus, the single piles behavior is modelled in 2D. Different researches show us that stabilizing a soil will reduce its settlement and the same is true for this research also, as the depth of treatment increased from 4m to 16m for the applied 1300KN load the settlement is reduced from -2.74cm to -1.17cm and while in the scenario of increasing the diameter from 0.6 to 0.8m maintaining the length of pile 16m the settlement obtained for the applied load is - 7.14cm and -1.42cm but it’s observed that there will be a significant change in reduction of magnitude of settlement by increasing the piles length maintaining the diameter minimum than both treating the soil and increasing the piles diameter. Therefore the conclusion here can be given that instead of treating the soil and increasing the piles diameter, elongating the length of the pile is recommended for the better reduction in settlement of the pile