Cyclic loading using flac3d software#

have studied the kinematic response of single piles using the Winkler model which considers the pile as a flexural beam. This model cannot give accurate results for the sophisticated loading conditions. In all analyses, the hyperbolic-hysteretic model was considered for soft clay. Zhang et al.вЂ™s study on the dynamic behavior of the pile-raft in soft clay showed that some critical factors such as peak acceleration, type of soil, and configuration of structure affect the pile behavior under the earthquake loads.

Cyclic loading using flac3d software#

In recent years, researchers have used various constitutive models using different software to investigate the seismic behavior of soils. Decreased soil strength and stiffness due to the weak soil or liquefaction may lead to the development of large bending moment and shear forces in the pile, which may lead to pile damage. For instance, the performance of piles in the loose saturated soils under seismic loads is an important issue due to the effects of increasing pore water pressure in them. Due to the construction of some structures in earthquake areas, investigating the seismic behavior of piles, especially in soft soils, has become a challenge for geotechnical engineers. Depending on the load type, soil, and structural conditions (such as dimensions of structure, distance between piles in a pile group, distance of the structure from bedrock and soil surface, definition of interaction type between structure and surrounding soil, etc.), the piles can be used in a group or single. When the bedrock or stiffer bottom layers are at the deeper depth below the soil surface, the pile is used for the gradual transfer of the loads.

Also, when the top layer or layers of soil are highly compressible or very weak so that the shallow foundation cannot be used to distribute the structural load, pile foundations are used to transfer the load to the stiffer bottom layers or bedrock. In case of low bearing capacity of soil for use of shallow foundations, deep foundations (pile foundations) are used. According to the results, the variation of earthquake frequency and intensity affects the bending moment created along the pile and also the distance between piles in a pile group affects the amount of the interaction between them. The results obtained from the numerical analysis of the soil-pile model are in relatively good agreement with the centrifuge model results. In all calibration methods, the cyclic shear and undrained cyclic triaxial tests are used. Three different methods have been used to calibrate the model parameters, two of them are new methods. This model can consider the soil stiffness degradation by increasing the number of cyclic loading. The aluminum material considering the linear elastic model has been used for the piles, and the nonlinear kinematic hardening model with Von Mises failure criterion has been considered for clay. Here, the seismic behavior of single pile and pile group constructed in saturated soft kaolin clay under three different earthquakes using Abacus 3D software is investigated. In geotechnical mediums where the bearing capacity of upper layers of soil is not suitable for use of the shallow foundations, piles are usually used as deep foundations to transfer loads to the stronger lower layers.