PileGroup 2.5 Release - New Features

We are pleased to announce that PileGroup 2.5 is released. This is a major update since we released PileGroup 2.4 in 2024. This release includes significant enhancements to the program workflow, a complete redevelopment of the calculation solver, and substantial improvements to results processing and presentation. The key enhancements and updates compared with the previous version are summarised below:

Version 2.5 - February 2026

New Features:

Input Program:

• The Input Program is now dedicated solely to defining and managing analysis inputs and no longer displays analysis results, as was the case in previous versions. All analysis results are now fully integrated within the Output Program, providing a clearer separation between model definition and results post-processing.

• A new Load tab has been added to the left-top panel, enabling users to define pile cap loading conditions directly within the model interface.

• The soil parameter and ground profile input windows have been updated to ensure consistency with the PileLAT and PileAXL programs. In previous versions, users were required to manually specify whether each soil layer was located above or below the water table. This is no longer necessary in Version 2.5. The new version introduces direct water table input, consistent with the implementation in PileLAT and PileAXL, resulting in a more streamlined and intuitive workflow.

• All p–y curve models available in the PileLAT program are now fully supported in PileGroup for the analysis of laterally loaded piles.

• All axial capacity methods available in the PileAXL program are now fully supported in PileGroup for the analysis of axially loaded piles.

• All t–z and q–z curve models available in the PileAXL program are now fully supported in PileGroup for the analysis of axially loaded piles.

• The pile section input window has been enhanced to include the specification of Poisson’s ratio. In Version 2.5, piles are modelled using Timoshenko beam theory, replacing the Euler–Bernoulli beam formulation adopted in previous versions for laterally loaded piles. This improvement allows shear deformation effects to be captured, providing a more rigorous representation of pile behaviour under lateral loading.

• The Analysis Options dialog has been further enhanced to include settlement analysis for piles subjected to axial loading within a pile group. Users can now specify the selected axial capacity method, as well as the associated T-Z and Q-Z curve model parameters for each soil layer, providing greater flexibility and control in the analysis.

• Detailed descriptions have been added beneath the Analysis Mode selection menu for both the Nonlinear Analysis Module and the Linear Analysis Module within the Analysis Options dialog.

• The Pile Layout Wizard input window has been enhanced to include an option for defining pile head connection conditions during pile group creation.

• The three-dimensional model within the Model Input sub-window can now be panned and rotated using the left and right mouse buttons. The 3D view of the pile group has been further enhanced, providing more intuitive and natural mouse-based navigation, as described below:

  • Pan View – Left-click and hold the mouse button while moving the mouse to pan the current three-dimensional view of the pile group.

  • Rotate View – Right-click and hold the mouse button while moving the mouse to rotate the current three-dimensional view of the pile group.

  • Zoom View – Scroll the middle mouse wheel to zoom in or out of the current three-dimensional view of the pile group.

• Each pile within the three-dimensional input model can now be individually selected using the mouse. Users can edit the selected pile properties or remove it from the current pile group as required. This functionality is newly introduced in Version 2.5.

  

• The global X, Y, and Z axes are now displayed in the bottom-right corner of the three-dimensional model view and dynamically update with model rotation, providing clearer spatial reference during navigation.

• The Linear Analysis Inputs dialog within the Linear Analysis Module has been enhanced to allow users to specify axial and lateral stiffness using either Young’s modulus or shear modulus. In addition, the program now supports the definition of pile free length above the ground surface.

  

• Soil layering correction based on the method proposed by Georgiadis (1983) is now supported in the program to consider the soil layering effects on the behaviour of laterally loaded piles.

• Pile cap loads input is now updated to allow users to input load cases at different locations on the pile cap, the program automatically converts all loads to the global coordinate origin of the pile cap.

  

• The Load Combination input has been enhanced to allow users to define load factors for each load case within each load combination. All analyses in the PileGroup program are performed using these load combinations, which are derived from the input pile cap loads.

  

• The Pile Group Effect dialog has been updated to provide four selectable options: no group effect, user-defined p-multipliers, or automatically generated p-multipliers based on Reese & Van Impe (2001) or Rollins et al. (2006).

  

• The soil layer, pile, load case, and load combination summaries can now be exported to an Excel-compatible CSV file or printed as a hard copy.

• The Analysis Run dialog has been enhanced to display the load step progression and pile cap deformation results, including maximum displacement, force error, analysis status, and any warning messages.

  

• The program has been validated and verified through the analysis of ten independent pile group case studies reported in the published literature. The computed results were systematically compared with the reference solutions. Full details of all validation examples are provided in a separate validation manual.

• Tutorial examples are provided to demonstrate step-by-step procedures for performing pile group analyses using the program. Complete details of all tutorial examples are presented in a separate tutorial manual.

• This release also includes further refinements to solver stability, performance optimisation, usability, and workflow efficiency throughout the program.

Output Program:

• The PileGroup output program is enhanced to provide a convenient and efficient way to access a wide range of analysis results, including pile cap responses, pile head (pile top) results, and detailed results along the pile length.

• A three-dimensional view of the analysis results is available through the 3D Model tab in the PileGroup Output window. This view allows users to visually inspect the pile group behaviour and response under the selected load combination.

• The Result Graph sub-window provides two-dimensional graphical plots of analysis results along the pile length for selected piles and load combinations. This view is intended for detailed examination, comparison, and interpretation of result distributions such as displacements, bending moments, shear forces, and axial forces.

• The Pile Group Multiple Results window is provided to allow users to view, compare, and envelope multiple analysis results for a selected pile under different load combinations.

  

• The Pile Head Results window is enhanced to present graphical and numerical results of pile head responses for a selected load combination. Results are displayed in plan view to illustrate the distribution of forces or displacements at pile heads across the pile group.

  

• In the PileGroup program, once the analysis is successfully completed, the user can view the P-Y, T-Z and Q-Z curve information at any depths along any pile within the group.

• The information such as pile axial load settlement and torque rotation curves for all the piles within the pile group can be viewed by users through the Pile-head stiffness (Settlement and Rotation) window.

• The PileGroup Report Generator is included to provide a structured and flexible interface for compiling analysis reports by allowing users to select specific model input data and analysis output results for inclusion in the final report. Report items are organised in a hierarchical tree structure, enabling clear and systematic selection of reporting content.