1. The two weightless rigid bars are connected by smooth pins. The rod
1-2 is of length a and the length of rod 2-3 is 2 a. All rotations are measured
positive counter clockwise from the vertical. At node 2, the rods 1-2 and
2-3 are connect by a torsional spring of stiffness kt and at node 3, rod 2-3
is connected by a linear spring of stiffness ks. Use Principle of Virtual
Works to determine the relationship between the load P and the angles θ1
and θ2 for equilibrium. Assume small angle deformation.
2. The structure made of two rigid pin-connected members joined by a
spring supports a vertical load at 3. Using the principle of complementary
virtual work find the horizontal displacement u of point 2 and the rotation θ13
of members 13, due to load P. The linear spring k24 = k.
3. The structure consists of one elastic bar and one rigid bar all connected by smooth pins. All elastic
bars have the same stiffness EA/L = 3.75(106) lb/in. Take P = 7.5(105) lb. Determine:
1. The displacements using the Principle of Virtual Work.
2. Member forces.