WORLD FOR CIVIL

Statics & Strength of Materials

Problems Assignment - Frames 3

Draw a complete free body diagram as a part of the solution for each problem.

1. A pin-connected A-frame supports a load as shown. Compute the pin reactions at all of the pins. Neglect the weight of the members. (Ay=1500 lb., Ey=1000 lb., Bx=1250 lb., By=1750 lb., Cx=1250 lb., Cy=250 lb., Dx = 1250 lb., Dy=750 lb., directions not indicated)

2. A simple frame is pin connected at points A, B, and C and is subjected to loads as shown. Compute the pin reactions at A, B, and C. Neglect the weight of the members. (Ax=10,100 lb., Ay=2500 lb,. Bx=10,100 lb., By=2500 lb., Cx=1443 lb., Cy=7500 lb., directions not indicated)

3. A pin-connected crane framework is loaded and supported as shown. The member weights are: post, 600 lbs.; boom, 700 lbs.; and brace, 800lbs. These weights may be considered to be acting at the midpoint of the respective members. Calculate the pin reactions at pins A, B, C, D, and E. (Ax=3824 lb., Ay=8100 lb., Bx=3824 lb., By=0, Cx=7768 lb., Cy=3279 lb., ED = 12, 650 lb @ 52.1^o , directions not indicated)

4. Sketch the structure and draw a free body diagram for the relevant member or the entire structure. Write the appropriate moment or force equations and solve them for the unknown forces. (Ax=500 lb., Ay=250 lb., Bx=500 lb., By=750 lb., Dx=100 lb., Dy=750 lb., directions not indicated)

5. Calculate the pin reactions at each point of the pins in the frame shown below. (Ax=300 lb., Ay=150 lb., Bx=300 lb., By=150 lb., Cx=300 lb., Cy=0, Dx =0, Dy=150 lb., Ey=150 lb., directions not indicated)

6. The tongs shown are used to grip an object. For an input force of 15 lb. on each handle, determine the forces exerted on the object and the forces exerted on the pin at A. (F = 48 lb. on object from each jaw., Ax = 0, Ay=63 lb.)