240 PRACTICAL STRUCTURAL DESIGN 



side of the support is equal to the shear on the same side. The 

 total reaction on any support is the sum of the positive and nega- 

 tive shear. 



To compute the shear and reactions proceed as follows: Shear 

 at A (+) = half the uniform load on span 1 to 2. The reaction 

 is equal to the shear. 



Shear on left of B (-) = total load on the span, less left reaction. 



Shear on right of B (+) = load on cantilever 3 to 4, P'US half 

 the load on the suspended span 4 to 5. 



Reaction on support B = sum of the + and shear, as found 

 above. 



Shear on left of C (-) = half the load on span 4 to 5, plus the 

 load on the cantilever 5 to 6. 



Shear on the right of C (+) = load on cantilever 6 to 7, plus 

 half the load on the suspended span 7 to 8. 



Reaction on support C = sum of the + and shear. 



Shear on the left of D ( ) = half the load on suspended span 

 7 to 8, plus the load on the cantilever 8 to 9. 



Shear on the right of D (+) = load on cantilever 9 to 10, plus 

 half the load on the suspended span 10 to 11. 



Reaction on support D = sum of the + and shear. 



Shear and reaction at E = half the load on the span 10 to 11. 



Check the results by using the formulas on page 52. 



The method for obtaining moments, shears, and reactions by 

 the use of "characteristic points" may be used for any number 

 of spans, equal or unequal, all spans loaded or some carrying a 

 live and dead load and others carrying only a dead load. 



