Chapter 8 - Deflections

Semester Overview

Chapter Topic
1 terminology
2-5 statics review
6 influence lines
8-9 deflections
10-12 indeterminate structures

 

Quiz 3 Topics

Deflections and Slopes

1. Integration / Superposition (deflection tables)    beams
2. Conjugate Beams
3. Virtual Work beams, trusses, frames

Deflection in Wood Structures

Structural Biomimetics

Quiz 4 & 5 Topics

Forces and Moments in Indeterminate Structures

1. Integration / Superposition Quiz 4    beams, trusses, frames
2. Conjugate Beams Quiz 4
3. Virtual Work Quiz 4
4. Slope-Deflection Quiz 4
5. Moment-Distribution Quiz 5

 

News

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"Pressure-Fighting" Strategies Can Help Prevent Choking In Stressful Situations

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Objectives

  • Visualize the shape of a beam's elastic curve.
  • Calculate the slope and deflection at various locations in a beam using the elastic-curve equation.
    • State the boundary, continuity and symmetry conditions.
    • Derive the elastic-curve equation.
      • Determine the distributed-load or moment function.
      • Integrate to determine the slope and elastic-curve functions.
        • Derive four indefinite integrals if starting with the distributed-load function.
        • Derive two indefinite integrals if starting with the moment function.
      • Solve for the integration constants.
  • Calculate the slope and deflection at various locations in a beam using the conjugate-beam method.
    • Determine the ground reactions on the real beam.
    • Draw the shear-force and bending-moment diagrams for the real beam.
    • Convert the real beam into its conjugate.
    • Load the conjugate beam with a distributed load having the same shape as M on the real beam divided by EI.
    • Draw the shear-force and bending-moment diagrams for the conjugate beam, or cut the conjugate beam at the desired location and determine V' and M' using equilibrium.
    • Convert the conjugate-beam information back to the real beam.  (V' = θ, M' = v)

Concepts  

1.  deflection diagrams and the elastic curve
2.  elastic-beam theory
3.  the double integration method
 - ce 110 statically-determinate deflection notes
 - ce 110 statically-indeterminate deflection notes
 - ce 110 deflection formulas
 - mecmovies
4.  moment-area theorems
5.  conjugate-beam method

Problems  

* examples to be discussed in class

7e
Examples
7e
Homework
Autodesk
Robot
integration
method

 

  08.001 -- -- solution solution
  08.002 -- -- -- --
  08.003 -- -- -- solution
  08.004 -- -- solution --
  08.005 -- -- solution --
  08.006 -- solution*3 -- --
  08.007 -- -- -- solution
  08.008 strategy solution*1 -- --
  08.009 -- solution*2 -- --
moment
-area
method
  08.010 strategy solution*1 -- --
  08.011  --  -- -- --
  08.012  --  -- -- --
  08.013  --  -- -- solution
  08.014  --  -- -- solution
  08.015  --  -- -- --
  08.016  --  -- -- --
  08.017  --  -- -- --
  08.018 -- solution*4 -- --
  08.019  --  -- -- --
    08.020    --    --   --   --  
    08.021   --   solution*2   --   --  
    08.022    --    --   --   --  
    08.023    --    --   --   --  
    08.024    --    --   --   --  
    08.025   --   solution*5   --   solution  
    08.026    --    --   --   --  
    08.027   --   solution*3   --   --  
  conjugate
-beam
method
  08.028   --   --   solution   --  
    08.029   --   --   solution   solution  
    08.030   --   --   solution   --  
    08.031   --   --   --   --  
    08.032   --   --   --   solution  
    08.033   --   --   --   solution  
    08.034   --   --   --   --  
    08.035   --   --   solution   --  
    08.036   --   --   solution   solution  
    08.037   --   --   --   --  
    08.038   --   --   solution   --