LPILE is a special-purpose and internationally recognized computer program based on rational procedures for analyzing a pile under lateral loading using the p-y method. LPILE solves the differential equation for a beam-column using a finite difference approach. The program computes deflection, bending moment, shear force and soil response over the length of the pile.

Nonlinear lateral load-transfer from the foundation to the soil is modeled using p-y curves generated internally using published recommendations for various types of soils, or user-inputted p-y curves. Specialized procedures are also available for computing p-y curves for layered soils and rocks.

With the first release dating back to 1986, LPILE has continuously been developed and improved to meet user needs and incorporate state-of-the-art literature and procedures.


Multi-Layered Soil Media

Choose from variety of built-in load-transfer (p-y) curves for modeling complex soil behavior under lateral loading. Some of the available curves include soft clay, stiff clay with or without free water, sand, liquefied sand, rock, Piedmont residual soil, cemented c-φ soil, Loess silt, elastic subgrade, and API soft clay with user-defined J. Alternatively, import your own user-generated p-y curves for analysis.

Piles and Shafts

LPILE slope ground surface
Model piles as either vertical or battered and consider sloping ground surfaces by adjusting internal modification factors. Specify boundary conditions at pile-head as free-head, pinned or fixed with sway, elastically-restrained with or without sway. See response of pile under lateral or bending moment, or specify lateral displacement or rotation at pile-head.


Specify user-defined multipliers to adjust for pile group effects in closely-spaced piles or to reduce pile response in liquefied layers for sustained long-term loading or seismic conditions. Consider soil-layering effects by adjusting p-y curves. Specify nonlinear resistance curves to consider tip shear resistance provided at the base of large diameter drilled shafts or short piles.


Specify distributed lateral loading along the length of the piles and shafts.

Load Combinations

Compute the response of piles up to 50 different user-defined load cases. For LRFD driven analyses, user can specify the load factors or LPILE can choose them.


Analyze and generate pile bending moment, shear force, mobilized sectional properties, or curvature of piles under each load case. LPILE uses finite difference method to discretize the underlying governing equations.


The average analysis takes only a few seconds.

Design Driven Analyses

Analyze different pile lengths to quickly determine the optimum pile penetration.


Plot the bending moment, shear force, mobilized section properties or curvature along the depth of the pile.


Compare the results of different load cases.


Detailed printer-friendly generated output files report all influencing parameters used for computation of internally generated p-y curves, deflection, bending moment, shear, mobilized soil reaction, moment-curvature, and more, with the option to to export all results into Microsoft Excel.

Features »