Structural engineering demo

Beam on Elastic Foundation Calculator

Explore beam response on a continuous elastic foundation. Define the member, foundation, and four load types to calculate shear, moment, deflection, and bearing pressure from the published workbook.

SpreadsheetWeb application example

About this structural analysis application

A beam on elastic foundation model represents a member supported continuously by soil, subgrade, or another compressible bedding material. The foundation reaction changes with the beam deflection, allowing engineers to study soil-structure interaction along the member.

This repository-native application keeps the analytical formulas in SpreadsheetWeb while presenting the model as a responsive, accessible browser interface. Valid changes recalculate automatically, and the original workbook report remains available as a PDF.

Live engineering model

Configure the beam and applied loads

Enter the beam and foundation properties, then add any combination of load types. Results update automatically when the configuration is valid.

Member and foundation

Beam properties

Length LftWidth BftThickness TftModulus EksiSubgrade modulus Kpci

Relative load map

Configured load positions

Positions and arrow heights are scaled relative to the current beam and load magnitudes.

Loading conditions

Applied loads

Blank rows are ignored. A load row must be either complete or entirely blank.

Uniform load wkips/ft

A constant load applied across the full beam length.

Workbook results

Calculated beam response

Maximum effects and diagrams are calculated by the published spreadsheet model.

Moment of inertia I—ft⁴

Foundation parameter β—ft⁻¹

Flexibility factor—βL

Beam criterionWaiting for model

Maximum positive shear+V(max)—

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Maximum negative shear-V(max)—

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Maximum positive moment+M(max)—

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Maximum negative moment-M(max)—

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Maximum deflectionD(max)—

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Maximum bearing pressureQ(max)—

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Response along the beam

Engineering diagrams

View complete result table 101 calculated points

Point	x (ft)	Shear (k)	Moment (ft-k)	Deflection (in)	Bearing pressure (ksf)
Waiting for calculated profile data.

Connecting to the live workbook…

Disclaimer

The information provided by this calculator is intended for informational and educational purposes only. The default figures shown are hypothetical and may not be applicable to your individual situation. We are not responsible for the consequences of any decisions or actions taken in reliance upon or as a result of the information provided by this tool. We are not responsible for any human errors or omissions.

Elastic-foundation analysis

What the calculator evaluates

The workbook combines beam stiffness with the modulus of subgrade reaction to calculate the member response at 101 positions along its length. The results show how applied loads are transferred into the continuous foundation.

Beam stiffness

Width, thickness, and elastic modulus determine the flexural rigidity used by the spreadsheet model.

Foundation response

The subgrade modulus represents a continuous linearly elastic support whose reaction follows beam deflection.

Combined loading

Uniform, linearly distributed, point, and applied-moment loads can be evaluated together in one case.

Response diagrams

Shear, bending moment, deflection, and bearing pressure are reported across the full member.

Structural and geotechnical uses

Explore soil-structure interaction scenarios

Pipelines and buried membersStudy how localized or distributed loading transfers through a continuously supported member.
Pavements and slabsCompare the influence of section stiffness and subgrade response.
Rail and bridge systemsVisualize shear and moment patterns under different load positions.
Engineering educationDemonstrate elastic-foundation behavior without distributing the source workbook.

Row	Start b (ft)	Load at b (kips/ft)	End e (ft)	Load at e (kips/ft)
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Row	Position a (ft)	Load P (kips)
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About this structural analysis application

Configured load positions

What the calculator evaluates

Explore soil-structure interaction scenarios

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