Module 5 : Force Method - Introduction and applications
Lecture 3 : Analysis of Statically Indeterminate Structures by Energy Method

Example 5.19 Determine the horizontal reaction of the portal frame shown in Figure 5.22(a) by energy method. Also, calculate the horizontal reaction when the member BC is subjected to distributed load, w over entire length.

 

 

Solution: Static indeterminacy of the frame = 1.

Let the horizontal reaction, H at D be the redundant. The reaction at A and D are

 

                                   

 

For the span AB ( x measured from A ),

 
                                   
 

For the span BE ( x measured from B ),

                                   
  For the span CD ( x measured from D ),
                                   
 

For the span CE ( x measured from C ),

                                   
   
   
   
1