Concept explainers
A Pratt roof truss is loaded as shown. Determine the force members FH, FI, and GI.
Fig. P6.55 and P6.56
The force in the members
Answer to Problem 6.56P
The force in the members
Explanation of Solution
The Pratt roof truss is loaded as shown in the figure. There is load at all the point on the top. The free body diagram of the given arrangement is given by Figure 1.
Figure 1
The total load on the truss is given from the figure as,
By symmetry the
The section’s free body diagram is given as,
The tangent of the angle
The angle is derived from the tangent value as,
From the diagram the sum of the moments in the counter clockwise direction about
From the diagram the sum of the moments in the counter clockwise direction about
From the diagram the sum of the moments in the counter clockwise direction about
Conclusion:
Solve for
Solve for
Solve for
Therefore, the force in the members
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Chapter 6 Solutions
Vector Mechanics for Engineers: Statics and Dynamics
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