LittleDef (fem1) v3.9.2

Lightweight 2D Structural Analysis for Unix & Windows

Overview

LittleDef is a portable, fast, and feature-rich 2D Finite Element Method (FEM) application. Originally designed for SGI IRIX workstations. It specializes in structural engineering, offering Eurocode-compliant verification for steel, concrete, timber, and masonry. Please note that the Eurocode part is now for reference only and it is incomplete.

Key Features

• Analysis Types: Linear Static, P-Delta (2nd order), Large Deformations, Modal (Frequencies), Seismic (Response Spectrum), and Elastic Stability (Buckling).
• Eurocode Design: Integrated verification modules for EN 1990 (Combinations), EN 1992 (Concrete), EN 1993 (Steel), EN 1995 (Timber), and EN 1996 (Masonry).
• High Performance: Sparse matrix assembly and solver, with an optional ANSI89 C accelerator for heavy computations.
• Portable: Pure Tcl/Tk 8.0+ codebase. Runs on IRIX, Linux, BSD, and Windows.
• Workflow: Native IRIX Interactive Desktop integration (FTR), CLI mode for headless reporting, and export to LaTeX, Markdown, EPS, XFIG, and CSV.

Requirements

LittleDef requires a Tcl/Tk interpreter version 8.0 or newer. You can find more information and downloads at the official Tcl/Tk website.

• Windows: We recommend the Magicsplat Tcl/Tk installer.
• Linux: Install using your package manager (e.g., sudo apt install tk on Debian/Ubuntu).

Usage

Launch the GUI using: wish fem1.tcl
Or run a headless analysis: wish fem1.tcl --solve model.df

Download

• Complete Package (Program + Documentation) - recommended
• User Guide (HTML)
• Theory Manual (HTML)