Nonlinear analysis of laterally loaded pile in layered soil medium 91. With the development of the finite element method, analysis using beam finite elements have been widely adopted in many calculations involving the subgradereaction approach or the py method. The elastic analysis is discussed, followed by a description of how calculation is done by this method. Analysis of pile foundation subjected to lateral and vertical. Analysis of laterally loaded piles in multilayered. Back analysis for prediction and behavior of laterally. Analysis of laterally loaded piles in sand considering scour hole. Keywords soilstructure interaction laterally loaded pile finite element analysis introduction the pile foundations are adopted to transfer the load from the structure to soil when the structure is embedded in a weak soil stratum. Development of py curves for analysis of laterally loaded. Analysis of laterally loaded short and long piles in multilayered.
Nevertheless, limited studies have been conducted to study the soil failure model around piles near a slope and the corresponding ultimate soil resistance characteristics. The maximum shear modulus of sand could be measured in situ by propagating shear waves through the soil. Laterally loaded pile groups have a group efficiency less than 1. Pile foundations usually find resistance to lateral loads from a passive soil resistance on the face of the cap, b shear on the base of the cap, and c passive soil resistance against the pile shafts. Flow chart for analysis of a laterally loaded pile in sandy soils. Finiteelement modelling of laterally loaded piles in a dense. Measured soilpile interaction pressures for smalldiameter. The py method of analysis of laterally loaded piles is analogous to the tz method described in chapter 7 to analyze the axially loaded piles.
Brian anderson, and andrzej nowak transportation research record 2019 2673. The study showed that, laterally loaded piles in sand can be analyzed within the working load range assuming a linear relationship between lateral load and lateral displacement at pile head. The soil reaction is dependent on the pile movement, and the pile movement is dependent on the soil reaction. In this thesis work a laterally loaded pile in cohesionless soil whose field test datas available is taken.
A simplified calculation method for the nearslope laterally. Davisson, department of civil engineering, university of illinois, urbana pile foundations usually find resistance to lateral loads from a passive soil resistance on the face of the cap, b shear on the base of the cap, and c passive soil resistance against the pile shafts. A pmultiplier, is used to modify py curve laterally loaded pile groups have a group efficiency less than 1. Pdf dynamic analysis of laterally loaded pile groups in. Deployment of the geosynthetic reinforced soil integrated bridge system from 2011 to 2017, synthesis. Analysis of laterally loaded piles using finite element free download as powerpoint presentation. In the py method, the pile is modelled as an eulerbernoulli beam and the soil resistance against the lateral pile movement is modelled using discrete springs.
Nonlinear response of laterally loaded rigid piles in sand abstract this paper investigates nonlinear response of 51 laterally loaded rigid piles in sand. Nonlinear analysis of laterally loaded single piles in. An analysis is presented for the horizontal displacement and rotation of a vertical pile subjected to lateral loading and moment, and situated in an ideal elastic mass. Nonlinear response of laterally loaded rigid piles in sand. The research described in fund set up by the following oil companies. Request pdf analysis of laterally loaded piles in sand considering scour hole dimensions scour is a process of soil erosion, which can occur around the foundations of bridges or offshore. Smallscale testing of laterally loaded monopiles in sand. Ef f ect of pile bending stif f ness on the py curve in sand 0 40 80 120 pile def lection, y, mm 0 100 200 300 400 s o i l p i l e r. Piles in trailing rows of pile groups have significantly less lateral load resistance than piles in the lead row. Klinkvort characterisation of magnesium, zinc and iron sulfates for thermochemical storage. The py method is widely used as a tool for analysis of laterally loaded piles. The analysis of laterally loaded piles is generally done using the py method matlock, 1970, reese et al. The proposed method estimates the distribution of lateral loads among piles in a pile group and predicts the safe design lateral load of a pile group. Assessment of the py method for laterally loaded pile in sand.
The behavior of laterally loaded piles was investigated using the finite difference computer program com623. The selection of adequate py curves is the most crucial problem when using this methodology for the analysis of laterally loaded piles reese and van impe, 2001. Up to ten different pile sections can be included in a single analysis. Request pdf analysis of laterally loaded piles in sand considering scour hole dimensions scour is a process of soil erosion, which can occur around the. Elastic beam relationships that are commonly used in analysis of laterally loaded piles are. Based on section 3, a computer code, swpile, was developed in fortran to analyze the laterally loaded pile.
The ability of the developed bnwf model to predict the response of a laterally loaded pile in sand is illustrated by comparing its predictions with field data. For this reason, a simplified method was developed herein for the analysis of laterally loaded piles in sand under a scour condition. The induced maximum bending moments and lateral displacements at pile head of laterally loaded piles decreased linearly as the values of pmultiplier. Amoco production company, chevron oil field research, esso production research company, mobil oil corporation, and shell. The university of alberta laterally loaded piles by. Influence factors are presented for a wide range of pile flexibilities and lengthtodiameter ratios, for both freehead and fixedhead piles. This paper is a companion to the paper entitled, field testing of laterally loaded piles in sand, by william r. The solution must satisfy a nonlinear differential equation as well as equilibrium and compatibility conditions.
Back analysis for prediction and behavior of laterally loaded single piles in sand ksce article pdf available in ksce journal of civil engineering 33. Geostructural nonlinear analysis of piles for performance. Abstract the response of laterally loaded pile groups is a complicated soilstructure interaction problem. The results of the proposed method are shown to be in good agreement with those obtained in situ. Simplified method for laterally loaded short piles in cohesionless soil victor aguilar, j. Analyses of lateral loaded piles with py curves connect ncdot. Jul 24, 2019 the paper presents the development of a threedimensional finiteelement model for pile tests in dense dunkirk sand, conducted as part of the pisa project. Analysis of laterally loaded piles in sand considering scour. Key words laterally loaded piles, py method, py curves, soil nonlinearity, pile groups, pile design, layered soil 18.
The py curves in this method were based on a wedge type of failure. The analysis is intended to serve as an independent alternative to the wellknown py method. Analysis of pile foundation subjected to lateral and. Users manual for lpile 20 using data format version 7 a program to analyze deep foundations under lateral loading by william m. To improve the design approach, a soil constitutive model representing smallstrain properties of sand was applied with threedimensional finite element method 3d fem models to simulate the laterally loaded piles.
For the single pile case, it is well known that the key factors that in. If the pile is loaded laterally so that a pile deflection yi occurs at the depth xi the soil stresses will become unbalanced as shown in fig. A laterally loaded single pile presents a soilstructure interaction problem. Nonlinear analysis of laterality loaded piles in cohesionless. Behavior of laterally loaded offshore wind monopiles in sands. A comparison is presented between measured and computed data on a laterally loaded. Pile group analysis, laterally loaded piles, py curves and. Behaviour of laterally loaded piles in layered soil deposits 706 poorly graded sand sp. Part i describes a study of loadtransfer criteria for analysis of axially loaded piles in sand using the discrete springs soil model. Lateral capacity of pile groups the lateral deflection of a pile group is typically 2 to 3 times larger than the deflection of a single pile. The input parameters for the soil are the angle of internal friction and a parameter characterizing. Both linear and nonlinear theoretical analyses were carried out to predict the model pile behaviour using the soil parameters observed by laboratory.
Laterally loaded piles pile group analysis py curves. Figure 48 head deflection as a function of applied force for a pile in sand. Development of py curves for analysis of laterally loaded piles in western washington author. These effects can be quantified only by the results of model tests. Aug, 2014 mod01 lec20 tension and lateral loaded piles nptelhrd. The interaction of piles in groups was also studied. The finite difference method of solving the differential equation for a laterally loaded pile is very much in use where computer facilities are available. Measured soilpile interaction pressures for smalldiameter laterally loaded pile in loose sand muhannad t. A thorough search of the literature was undertaken to find the results of lateral load tests performed in clay and sand.
Dynamic analysis of laterally loaded pile groups in sand and clay. A part of the authors study on the behavior of batter piles, based on his own research work, has been included in this chapter. According to meyerhofs method, a pile can be defined as flexible if kr relative stiffness of pile e l4 e i s p piles in sand. The reference displacement yc is calculated by the equation below.
Oneill, sunnnarizes the results of previous research and presents criteria for designing drilled shafts. It is proven that laterally loaded piles embedded in sand can be analyzed within the working load range assuming a linear relationship between lateral load and lateral displacement. Evaluation of the lateral response of micropiles via full scale load testing. Analysis of laterally loaded piles using finite element. A laterally loaded single pile is a soilstructure interaction problem. Analysis of laterally loaded piles in multilayered soil deposits. The results of these analyses indicate thatmost of. Although fairly reliable methods are developed to predicate the lateral behavior of single piles, the lateral response of pile groups has attracted less attention due to the required high cost and complication implication.
For laterally loaded pile groups, full scale tests conducted by oneill 3 and huang et al. An investigation of the natural microscale mechanisms that cause volume change in expansive clays. Available criteria for spring representation of soil are presented and. In essence, the method consists of dividing the pile into a series of increments of equal length. As an alternative to driven piles or drilled shafts, micropiles can provide substantial support while minimizing cost, environmental impact, and harmful construction. However, several items may still need additional research to overcome some identified possible limitations. The results of a numerical analysis of single laterally loaded piles embedded in cohesionless soils, taking soil yielding into account, are presented. Lateral load capacity of piles transportation research board. Extensive theoretical and experimental investigation has been conducted on single vertical piles subjected to lateral loads by many investigators. The results of these analyses indicate thatmost of the py criteria, where p is the. The accuracy of the procedure was evaluated by comparing the computed response of the pile groups at the kentland farms load test facility to the results of the load tests discussed in chapter 6. Schematic of laterally loaded pile in multilayered elastic soil deposit.
The soil is composed of 6% fine sand, 18% silt and 76% clay. An analysis of the dynamic lateral response of pile groups is described. Figure 2 py curve for soft clay api model under cyclic loading condition. The purposes of this paper are to estimate the behavior of laterally loaded single piles by the back analysis and the effects of nonhomogeneity consisted of two layers, constraint condition of pile head, relative density, and embedded length of pile on the behavior of single pile in sand. Users manual for laterally loaded pile analysis program for the microcomputer, com624p version 2. The pile is discretized into small segments and each pile segment is assumed to be attached to a soil spring. A lateral load test was performed on a fullscale pile to establish the py curve criteria for piles in sand. Evaluation of the lateral response of micropiles via full. Loadtransfer criteria for numerical analysis of axially. These experiments provided the first available data on soil pile interaction during lateral spreading under realistic time histories of very intense, earthquake shaking. Laterally loaded piles and computer program com624g. Back analysis for prediction and behavior of laterally loaded single. The pile is modeled with structural beam elements and can be assigned either linearelastic or elasticperfectly plastic material properties. Pdf analysis of laterally loaded piles in multilayered soil deposits.
Jun 06, 2014 for this reason, a simplified method was developed herein for the analysis of laterally loaded piles in sand under a scour condition. Analysis method for laterally loaded pile groups using an. Mod01 lec20 tension and lateral loaded piles youtube. A brief overview of the laterally loaded pile problem and a description of the methodology used in lateral pile analyses also are presented in this chapter.
Empirical approach based on centrifuge testing for cyclic deformations of laterally loaded piles in sand p. The university of alberta laterally loaded piles by brynja. Lateral capacity of pile groups the lateral capacity of an individual pile in a group is a function of its position row in the group, and the ctc pile spacing. Under lateral loading, the py curves of a pile group differ from those of a single pile due to group effects. The ultimate soil resistance near the ground surface was developed based on a wedge type failure theory. Pdf back analysis for prediction and behavior of laterally. Pile design software, pile group analysis, laterally loaded piles, py curves, free download and rock socket. Simplified analysis of laterally loaded pile groups. Today, the py method is the most widely used method for calculating the response of laterally loaded piles. The computed responses compared well with the predictions of the twodimensional analysis. Analysis of laterally loaded piles in sand by lymon c. Dynamic analysis of laterally loaded pile groups in sand.
Hence, py curves of single piles are modified by reduction factors for either a row. Numerical analysis of pile behavior under lateral loads in. Simplified method for laterally loaded short piles in. The induced maximum bending moments and lateral displacements at pile head of laterally loaded piles decreased linearly as the values of p multiplier. Pdf behaviour of laterally loaded bridge piles in sand. Brian anderson micropiles are a relatively new deep foundation technology in the united states. In the design of laterally loaded monopiles, the p. The effects of the scour hole dimensions on the response of laterally loaded piles in sand were evaluated using this simplified method. Measured response of each pile test was used to deduce input parameters of modulus of subgrade reaction and the gradient of the linear limiting force profile using elasticplastic solutions. Analysis of laterally loaded piles in sand semantic scholar.
Criteria for the design of axially loaded drilled shafts. The liquid limit of the soil is 86%, plastic limit is 29% and plasticity index is 57%. Investigation of lateral load resistance of laterally. The py curve based methodology for analysis of laterally loaded piles is easy and reliable empirical in nature, but backed by decades of experience. Model concrete piles were driven into a uniformly prepared sand bed and were loaded to failure while observing the load deflection behaviour. Analyses of lateral loaded piles with py curves observations on the. Figure 2 schematic showing py model used for analysis of laterally loaded piles x 1 x 2 x n x n1 lateral load nonlinear springs il. Geotechnical design tools for soilstructure interaction problems such as pile groups, laterally loaded piles, nonlinear py curve generation and rock socket design.
Mesh of single pile model, side view, top eight layers of. Analysis of laterally loaded piles in multilayered soil. Introduction the report documents the development of a new method of analysis of laterally loaded piles. This document is available to the public through the national technical information service, springfield, va 22161 19. In order to properly analyze a laterally loaded pile foundation in soilrock, a nonlinear. Generalized solutions for laterally loaded vertical piles are given by matlock and reese 1960. The proposed models were incorporated into an fea program ansys which was used to compute the response of a laterally loaded pile. The project was aimed at developing improved design methods for laterally loaded piles, as used in offshore wind turbine foundations. Analysis of laterally loaded piles in sand onepetro. Abstract data were taken during the lateral loading of two 24in. Empirical approach based on centrifuge testing for cyclic. Pdf analysis of laterally loaded piles in multilayered.
This method is quite popular in the usa and in some other countries. Dynamic analysis for laterally loaded piles and dynamic py. The governing differential equation equation 66 is solved using the finite difference technique. Generalized cyclic py curve modeling for analysis of. Back analysis for prediction and behavior of laterally loaded. Analysis of laterally loaded piles in sand considering.
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