Analysis of laterally loaded single pile using P-y curve by Program GEO Tools

Part I: Numerical Models

The Analysis of laterally loaded single pile by P-y curve program offers a simple user interface while enabling advanced analysis options for both academic and practical applications. It supports multiple nonlinear soil models through P-y curves representing a variety of ground conditions, including soft clay, stiff clay (with and without water), sand, API-based soils, modified stiff clays, c–φ soils, silt, weak and strong rock, loess, and liquefied soils.

The pile is modeled as a beam element, with the option to choose between Euler-Bernoulli and Timoshenko beam theories. The program generates the pile stiffness matrix and incorporates nonlinear soil springs derived from selected P-y curves to form a pile–soil stiffness matrix. This system is solved using three numerical methods: Finite Element Model with Euler beam (FEM_E), Finite Element Model with Timoshenko beam (FEM_T), and Finite Difference Model (FDM).

In addition to soil nonlinearity, the program allows users to consider the nonlinear material behavior of the pile or column itself, with support for common structural materials such as steel and concrete. Users can define the pile as a linear elastic material, or select from several nonlinear cross-section types, including:

• Elastic circular section
• Circular reinforced concrete section
• Steel pipe section
• Circular reinforced concrete section with casing
• Circular steel tube section filled with concrete

For nonlinear reinforced concrete or composite sections, the pile can be analyzed according to international design standards such as:

• ACI 318 (American Concrete Institute)
• EC2 (Eurocode 2)
• ECP (Egyptian Code of Practice)
• IS 456 (Indian Standard)
• BS 8110 (British Standard)
• CP 65 (Singapore Code)
• CSA A3 (Canadian Standard)
• HK CP (Hong Kong Code of Practice)
• Or a custom-defined set of design parameters

Further, the program includes the Georgiadis layering correction option to account for the variation of soil stiffness with depth in layered soil profiles, improving the accuracy of displacement predictions near the surface.

The validity of the implemented methods is verified through comparisons with field data and published research. Numerous examples are provided to illustrate the program’s capabilities in modeling laterally loaded piles across various soil and material conditions.