DYNAMIC RESPONSE OF INCLINED MICRO-PILES IN LAYERED SOILS

Complexity forces in deep foundations, such as pilesand micro-piles to dynamic analysis, are most importantparts of analyzing. Low eect seismic destructionis considered to run this type of foundations. In thepresent article, Micro-piles modeling have been investigatedfor double groups by applying dierent angles,including 150, 200, 250, 300, 900 using ABAQUS software.Soil environment has been modeled in both Singlelayerand that which is layered with consider makingtwo types of elastic,plastic behaviors with Drucker-Prager model. In both cases, is investigated the eectsof soil with soil,micro-pile interaction have been investigated,on micro-piles behavior. Dynamic analysiswas carried out with the vertical load to cap the micropilesand by entering acceleration onto the model oorwith assuming linear attenuation by El-Centro earthquakerecord,sinusoidal harmonic acceleration. Atthe end, evaluation of these changes in stress distributionin the soil, the relative displacement, change of bendingmoments,axial forces for homogeneous,nonhomogeneoussoils has been carried out. Dynamic analyseshave shown that angel of micro-piles from verticalto2502da is the cause of the reduction of the stress levelin the soil. The maximum bending moments,axialforces occur near the cap of the micro-pile,continuethe depth of micro-piles, this change is minimal. Thissubject states proposes micro-pile importance in reducingdisplacement, especially in cases of the soil with layers.Due to damping within the upper layers of soil andmicro-pile's cap, soil stress distribution has increased,moreover, due to the eect of gravity in more depth ofmicro- pile, tensions have been reduced in the surroundingsoil.In homogeneous soil, 20- degree angle is suitable formicro-pile angle,the angle of the non-homogeneoussoil is 15 degrees for a better distribution of stress. Comparingthe relative displacement values,uplift valuesof homogeneous,heterogeneous soils surrounding themicro-pile 20- degree angle to the right angle is placedin the soil.