Structural Calculator

Foundation Design Calculator

Design isolated, strip, and combined footings per ACI 318-19M. Perform bearing capacity, settlement, shear, and flexure checks instantly with interactive graphics and exportable PDF reports.

ACI 318-19M · LRFD · SI Units

What This Calculator Can Do

A comprehensive foundation design toolset built for practicing structural engineers.

Isolated, Strip & Combined Footings

Design all common footing types with automatic geometry sizing and reinforcement layout.

Bearing Capacity Check

Verify soil bearing pressure against allowable capacity with automatic eccentricity corrections.

Settlement Analysis

Estimate settlements using the subgrade modulus (Winkler spring) method for immediate deformation predictions.

Punching Shear (ACI 318-19)

Two-way shear check at critical perimeter per ACI 318-19 Section 22.6 with all applicable modifiers.

One-Way Shear Check

Beam-action shear verification at distance d from column face per ACI 318-19 provisions.

Flexure Design (As Required)

Calculate required steel area for bending in both directions with minimum reinforcement checks.

Uplift Check

Verify footing stability against net uplift forces including self-weight and overburden resistance.

Water Table Effects

Account for groundwater level influence on effective soil stress and bearing capacity reduction.

Biaxial Eccentricity

Handle moments in both X and Y directions with kern distance checks and pressure redistribution.

Interactive Canvas Graphics

Live plan view and section views rendered on HTML5 canvas, updating as you change parameters.

Step-by-Step Calculation Sheet

Full engineering calculation report with formulas, intermediate values, and code references.

PDF Export

Export professional calculation reports to PDF for documentation, review, and project records.

How It Works

Get from inputs to a complete foundation design in four simple steps.

1

Enter Parameters

Input column loads, soil properties, footing geometry, material strengths, and water table depth.

2

Auto-Calculate

The engine runs all checks instantly: bearing, settlement, shear, flexure, uplift, and eccentricity.

3

Review Results

Inspect pass/fail cards, interactive plan and section views, and the full step-by-step calculation sheet.

4

Export PDF

Generate a professional calculation report with all inputs, results, code references, and graphics.

Standards & Codes

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