It influences the behavior of soil, as well as the response of pile under loading. In the Calculation program, it is specified how the (dynamic) load multiplier changes with time rather the input value of the load.Soil–structure interaction plays an important role in the behavior of structure under static or dynamic loading. If a particular load system is set as a dynamic load, the load is initially kept active, but the corresponding load multiplier is set to zero in the Input program. Input program) to produce the actual load magnitudes.
PLAXIS 2D (2012) was used for the finite element analysis of.PLAXIS 2D Advanced enhances your geotechnical design capabilities with more advanced features and material models to consider creep, flow-deformation coupling through consolidation analysis and steady state groundwater or heat flow. A detailed literature review on soil–structure interaction analysis of laterally loaded piles is presented in this paper.for dynamic loading conditions considering seismic design parameters corresponding to the. The analysis became easier with the debut of powerful computers and simulation tools such as finite element analysis software. The difficulty in the accountability of the influencing factors necessitates a careful study on soil–structure interaction problem. In a laterally loaded pile the load is resisted by the soil–pile interaction effect, which in turn depends on soil properties, pile material, pile diameter, loading type and bed slope of ground. The soil–pile system behavior is predominantly nonlinear and this makes the problem complicated.
The lateral forces are due to the wind, wave, earthquake, dredging, and impact loads. Pile foundations are subjected to significant amount of lateral forces in addition to the vertical forces. In an axially loaded pile, the load is transferred to the soil through the side friction at the soil–pile interface and base resistance offered by the soil bed. Numerical simulation using three geotechnical software namely Slope/W, SV-Slope and Plaxis 2D.The pile foundations are adopted to transfer the load from the structure to soil when the structure is embedded in a weak soil stratum.
The present study focuses on the significant factors affecting the soil–structure interaction of laterally loaded pile foundation (LLP). The effects of vertical loads on the piles are well established through these years, whereas studies on vertical piles under lateral loads are limited and are continuing to establish a well-defined method of analysis considering the effect of all the influencing parameters. The current design practices consider the influence of these two loadings independently and hence pile designs are carried out separately for vertical and lateral loads. Studies showed that the influence of vertical load on the lateral response is not so significant when the vertical load is applied simultaneously with the lateral load. The lateral load is resisted by the soil–pile interaction effect , which in turn depends on pile material, pile diameter, soil properties, and bed slope of ground.
To calculate the pile cap deflection and rotation the pile has been idealized as a beamas shown in Fig. Lateral loads on piles cause deflection and rotation of pile caps. Earlier developments in the theoretical formulations are also discussed here. The theoretical formulations are to be studied for the advanced modifications in the numerical formulations. Theoretical investigationTheoretical investigations are the basis of numerical formulations. For better understanding of the literature, they are grouped based on the type of investigation carried out to study the behavior of LLPs.
SW model analysis predicts the response of LLPs and had shown very good agreement with actual field tests in sand, clay and layered soils. 3 was suggested and was found to have advantages over p– y curve method. Further, the strain wedge (SW) model as shown in Fig. To analyze the behavior of a LLP. Such an attempt was done by Mazurenko et al. Further the soil–structure interaction can be incorporated by considering the effect of soil parameters.
In the study, pile was idealized as one-dimensional beam element, pile cap as two-dimensional plate element and soil as nonlinear elastic springs using modified p– y curves. Have extended the work of Reese and derived finite element formulation for the nonlinear analysis of pile groups subjected to lateral loads using p– y curves. A modification of this has been suggested by Poulos–Focht–Koch in which the pile group has been considered as a large diameter pile. The importance of various parameters involved in the solution is studied using different analytical approaches. Who have already developed p– y method for laterally loaded single pile have presented the analysis of a cluster of piles.
Tipical Dynamic Loading For Plaxis 2D Free Head And
Both free head and fixed head methods are considered here. And developed an analytical method which uses fundamental basis of structural mechanics to obtain the governing equation of the soil–pile system. It was modified by Horwath with additional case of Young’s modulus varying with depth for layer of finite thickness.The response of single pile subjected to lateral load in layered soil was further studied by Rongqing et al. In a simplified analysis the vertical soil profile was considered uniform, suggested by Reissner as shown in Fig. The proposed p–y curves with an improved wedge model are more appropriate and realistic for representing a pile–soil interaction for LLP in clay than the existing p– y method.The behavior of soil becomes complex when the change in its property along the vertical profile is considered. Have conducted studies on pile–soil system subjected to lateral loads in clay soil by improved wedge failure model and hyperbolic p– y criteria.
Later, a detailed investigation by Banerjee et al. Furthermore, certain studies suggest two-dimensional mapped infinite elements and nonlinear stress–strain behavior of the soil using hyperbolic fit. The stress strain behavior of most geo-materials is highly nonlinear at all phases of loading and s-shaped degradation curve as shown in Fig. The existing methods were later modified considering the nonlinear elastic properties and modulus degradation characteristics of soil. The direct shear test was used to determine modulus of soil resistance and ultimate soil resistance.
Numerical investigationA set of numerical formulations for advanced analysis of soil–structure interaction is developed by many researchers. Even though the incorporation of soil layering in the theoretical formulation of LLP makes the solution more complicated, adopting finite element analysis techniques as well as computational power of latest computers can produce accurate results. Solutions are obtained for pile response with various cohesionless soils taking into account the short pile and long pile behavior.Through these years, theoretical investigations have developed solutions for LLPs and pile groups embedded in homogeneous as well as layered soil. Researchers have developed finite element formulations and its MATLAB coding by considering modulus of subgrade reaction approach to analyze fixed head and free head single piles in cohesionless soil. Studies present inelastic pile–soil–structure interaction under static loading with piles modeled using linear beam column finite elements and soil was modeled using nonlinear springs.
, to study the seismic pile response of a structure–pile–soil system with uncertain soil and concrete properties. Input energy was expressed in time domain as,A newly developed updated reference point (URP) method was used by Okada et al. 6 and derived the energy transfer function, which plays a key role in the input energy calculation.
It was observed that the response of flexible base structure was more, about 15–20 % compared to fixed base structures. The study was conducted on an axisymmetric multistoried building and the peak response of the building under fixed base condition and flexible base condition were studied. It was also found that the variability of equivalent shear wave velocities of soil, even at a deep underground influences the bending moment at the pile head.Seismic soil–structure interaction of a pile group was studied using equivalent pier method (EPM) by Badry et al. It was confirmed in the studies that the NURP method can be applied to the seismic pile response in terms of the structure–pile–soil system with an acceptable accuracy and the worst variation for weak soil parameter are to be clarified.
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