# Homework Help: Calculation of Bending Moments and beam deflection

1. Nov 21, 2012

### mm391

1. The problem statement, all variables and given/known data

The picture of the beam below has a module of rigidity EI, determine the reactions at the supports and the equation of the deflection curve of the left half of the beam

2. Relevant equations

v*EI=((Ma*x2)/2)+((Ra*x3)/6)

Ʃ of Forces in Y direction = Ra+Rb=0
Ʃ Moments about A = Ma-Mo+Mb-Ra*L

3. The attempt at a solution

How do I go about finding Ra and Rb and Ma and Mb?

For the left had side of the beam the bending moment equation is Ma+Ra*x

Putting x = L/2 in to the defelction equation gives me:

((Ma*L^2)/(8EI))=((-Ra*L^3)/(48EI))

2. Nov 21, 2012

### SteamKing

Staff Emeritus
Where's your picture of the beam?

3. Nov 21, 2012

### mm391

Sorry I forgot to add the picture. It should be attached now.

#### Attached Files:

• ###### Untitled.jpg
File size:
8.7 KB
Views:
166
4. Nov 21, 2012

### SteamKing

Staff Emeritus
The beam is statically indeterminate. You'll need to use double integration of the bending moment curve and the boundary conditions at the ends of the beam to solve for the reactions and moments at the ends.