1. Bridge Truss problem I (simple truss)
Moments
Principles of EngineeringTM
Unit 4 – Lesson Statics
Bridge Truss problem I (simple truss)
Problem: A 10,000-lb load is carried by the bridge truss as shown. What is the weight being carried at either end (i.e. at ‘A’ and ‘D’)
Draw the reaction forces at A and D
Choose A as the pivot point. Use ΣM = 0 to solve the reaction force at D.
Then use ΣFY = 0 to solve the reaction force at A. B
18 ft A D
24 ft C
44 ft
Fc = 10,000. lbs

2. Bridge Truss problem II (cantilever)
Moments
Principles of EngineeringTM
Unit 4 – Lesson Statics
Bridge Truss problem II (cantilever)
Problem: A 10,000-lb load is carried by the cantilevered truss as shown. What is the weight being carried at ‘A’ and ‘C’?
Draw the reaction forces at A and C
Choose A as the pivot point. Use ΣM = 0 to solve the reaction force at C.
Then use ΣFY = 0 to solve the reaction force at A. B
18 ft A D
24 ft C
44 ft
FD = 10,000. lbs