Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

This is an AMP page - Open full page! for all features.

Search is the most efficient way to navigate the Engineering ToolBox!

Continuous Beams - Moment and Reaction Support Forces

Sponsored Links

Continuous Beam with Distributed Load

For a continuous beam with 3, 4 or 5 supports and distributed load the reaction support forces can be calculated as

R = cr q L                     (1)

where

R = reaction support force (N, lbf)

cr = reaction support force coefficient from the figure above

q = distributed load (N/m, lbf/ft)

L = span length (m, ft)

The moments can be calculated as 

M = cm q L2                     (2)

where

M = beam moment (Nm, lbf ft)

cm = moment coefficient from the figure above

.

Example - Continuous Beam with Distributed Load

The reaction forces in the end supports for a continuous beam with 3 supports and distributed load 1000 N/m can be calculated as 

Rend = (0.375) (1000 N/m)

         = 375 N

         = 0.38 kN

The reaction force in the center support can be calculated as

Rcenter = (1.250) (1000 N/m)

         = 1250 N

         = 1.25 kN

The beam moments at the middle of spans with span length 1m can be calculated as 

Mend = (0.070) (1000 N/m) (1 m)2

        = 70 Nm

The beam moment at the center support can be calculated as 

Mcenter = (0.125) (1000 N/m) (1 m)2

        = 125 Nm

Continuous Beam with Point Loads

For a continuous beam with 3, 4 or 5 supports and point loads the reaction support forces can be calculated as

R = cr F                      (3)

where

cr = reaction support force coefficient from the figure above

F = point load (N, lbf)

The moments can be calculated as 

M = cm F L                     (4)

where

cm = moment coefficient from the figure above

Example - Continuous Beam with Point Loads

The reaction forces in the end supports for a continuous beam with 3 supports and 2 point loads 1000 N can be calculated as 

Rend = (0.313) (1000 N)

         = 313 N

         = 0.31 kN

The reaction force in the center support can be calculated as

Rcenter = (1.375) (1000 N)

         = 1375 N

         = 1.4 kN

The beam moments at point loads with span length 1m can be calculated as 

Mend = (0.156) (1000 N) (1 m)

        = 156 Nm

The beam moment at the center support can be calculated as 

Mcenter = (0.188) (1000 N) (1 m)

        = 188 Nm

Sponsored Links

Related Topics

Beams and Columns

Deflection and stress in beams and columns, moment of inertia, section modulus and technical information.

Related Documents

Beam Loads - Support Force Calculator

Calculate beam load and supporting forces.

Beams - Fixed at Both Ends - Continuous and Point Loads

Stress, deflections and supporting loads.

Beams - Fixed at One End and Supported at the Other - Continuous and Point Loads

Supporting loads, moments and deflections.

Beams - Supported at Both Ends - Continuous and Point Loads

Supporting loads, stress and deflections.

British Universal Columns and Beams

Properties of British Universal Steel Columns and Beams.

Cantilever Beams - Moments and Deflections

Maximum reaction forces, deflections and moments - single and uniform loads.

Drawbridge - Force and Moment vs. Elevation

Calculate the acting forces and moments when elevating drawbridges or beams.

HE-A Steel Beams

Properties of HE-A profiled steel beams.

HE-B Steel Beams

Properties of HE-B profiled steel beams.

Three-Hinged Arches - Continuous and Point Loads

Support reactions and bending moments.

Wood Beams - Strength of Material

Bending and compression strength of wood species used in beams.

Sponsored Links

Search Engineering ToolBox

Search is the most efficient way to navigate the Engineering ToolBox!

SketchUp Extension - Online 3D modeling!

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp from the Sketchup Extension Warehouse!

Privacy

We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Google use cookies for serving our ads and handling visitor statistics on the AMP pages. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

AddThis use cookies for handling links to social media. Please read AddThis Privacy for more information.