Portal Frame Analysis Application

A comprehensive structural engineering tool that performs portal frame analysis and design for multi-story, multi-bay steel frames. Features a modern MUI frontend, Python FastAPI backend, and Julia calculation engine with LaTeX-rendered calculations.

Architecture

frontend/     React + TypeScript + MUI v5 + KaTeX
  |
  v  (HTTP/JSON)
backend/      Python FastAPI
  |
  v  (subprocess JSON)
julia/        Julia + Handcalcs + Unitful

Frontend (React + MUI)

• Material UI v5 with professional engineering theme
• Multi-section input form (Geometry, Forces, Material, Design)
• 5-tab results dashboard (Portal, Gravity, Combinations, Beam Design, Column Design)
• KaTeX LaTeX rendering for handcalc-style equations
• Responsive layout with drawer navigation

Backend (Python FastAPI)

• REST API at http://localhost:8000
• POST /api/analyze - Full analysis with LaTeX rendering
• POST /api/analyze/fast - Quick computation (no LaTeX)
• GET /api/aisc-sections - W-section database
• GET /api/health - Health check
• Calls Julia engine via subprocess with JSON I/O

Calculation Engine (Julia)

• Handcalcs.jl + Unitful.jl + Latexify.jl for rendered calculations
• @smartmath macro for fast/render toggle (no duplicate code paths)
• Typed solution structs for type-safe pipeline
• Pure solver functions with validation at boundary
• JSON adapter: run(params::Dict) pattern

Screenshots

Portal Method Diagrams (Lateral Load Analysis)

Column Shear Forces

Column Moment Diagram

Beam Moment Diagram

Beam Shear Diagram

Beam Axial Diagram

Approximate Method (Gravity Load Analysis)

Frame 1 - Dead Load

Frame 1 - Live Load

Frame 2 - Dead Load

Frame 2 - Live Load

Frame 3 - Dead Load

Frame 3 - Live Load

Frame A - Dead Load

Frame A - Live Load

Frame B - Dead Load

Frame B - Live Load

Frame C - Dead Load

Frame C - Live Load

Structural Analysis Features

Portal Method (Lateral Load)

• Column shear distribution (exterior/interior)
• Column bending moments
• Beam moments from column equilibrium
• Beam shear forces
• Column axial forces (cumulative from top)

Distributed Load Analysis (Gravity)

• Dead and live load distribution
• Slab force tributary area calculations
• Beam bending moment (0.8L clear span approximation)
• Beam shear force

Load Combinations (AISC)

• Combo 1: Dead + Live
• Combo 2: Dead + 0.7 * Earthquake
• Combo 3: Dead + 0.75 * Live + 0.525 * Earthquake

AISC Steel Design

• Beam: Sx required, compact section check, LTB cases, shear check
• Column: K-factor (alignment chart), slenderness, Fa, interaction equation
• Automatic W-section selection from database

Quick Start

Prerequisites

• Node.js 18+
• Python 3.9+
• Julia 1.9+

1. Start Backend

cd backend
pip install -r requirements.txt
python server.py
# Server runs at http://localhost:8000

2. Start Frontend

cd frontend
npm install
npm run dev
# App runs at http://localhost:5173

3. Julia Setup (first time)

cd julia
julia --project=. -e 'using Pkg; Pkg.instantiate()'

Default Example (Pihuts)

• 3 storeys, 2 bays
• Heights: 4m, 3m, 3m
• Bay widths (ABC): 6.0m, 5.5m
• Bay widths (123): 7.0m, 6.0m
• Lateral forces: 21.88, 38.29, 40.96 kN
• Fy = 248 MPa

Units

All calculations use SI units internally:

• Length: meters (m)
• Force: kilonewtons (kN)
• Stress: megapascals (MPa)
• Mass: kilograms per cubic meter (kg/m^3)

Reference Data

The data/ directory contains AISC W-section properties in CSV format.

Calculation scope and validation status

This is an independent engineering-software implementation of approximate portal-frame and gravity-load methods, with steel-member design checks. The visible diagrams and rendered equations make the calculation path inspectable.

The repository does not currently provide a published independent benchmark suite or a passing CI calculation-validation report. Approximate analysis assumptions and a particular code edition must be checked for each intended use; screenshots alone do not validate the numerical results.

Start with the default example above to inspect inputs, units, intermediate results and diagrams. A documented comparison against independently solved reference cases remains the next validation step.