(a)
Whether a
Answer to Problem 5.15.6P
Adequate
Explanation of Solution
Given:
Total gravity load = 40 psf of roof surface
Formula used:
Lpis unbraced length in an inelastic behavior
Lris unbraced length in an elastic behavior
Mn is nominal moment strength
Mpis plastic moment capacity
Calculation:
Determine the nominal flexural strength about x and y axes:
Neither the beam design charts nor the Z tables include shapes smaller than W8, so the flexural strength of the
From the dimensions and properties tables, the shape is compact.
The following properties of a
A is Cross-sectional area
Sxis Elastic section modulus about X -axis
Zxis Plastic section modulus about X -axis
Iyis Moment of inertia about Y -axis
ryis Radius of gyration about Y -axis
Syis Elastic section modulus about Y -axis
Cwis Warping constant
h0is Distance between centroid of flanges
J is Torsional moment of inertia
For
From the below given figure in the textbook,
For the y axis, since the shape is compact, there is no flange local buckling
Check the upper limit:
Roof load: Combination 3 controls
where,D is dead load and S is snow load
Tributary width =
Purlin load =
Component normal to roof =
Component parallel to roof =
Calculate factored bending moment about x axis and y axis
Use ½ of weak-axis bending strength in the interaction equation:
Conclusion:
(b)
Whether a
Answer to Problem 5.15.6P
Adequate
Explanation of Solution
Given:
Total gravity load = 40 psf of roof surface
Formula used:
Lpis unbraced length in an inelastic behavior
Lris unbraced length in an elastic behavior
Mn is nominal moment strength
Mpis plastic moment capacity
Calculation:
Determine the nominal flexural strength about x and y axes:
Neither the beam design charts nor the Z tables include shapes smaller than W8, so the flexural strength of the
From the dimensions and properties tables, the shape is compact.
The following properties of a
A is Cross-sectional area
Sxis Elastic section modulus about X -axis
Zxis Plastic section modulus about X -axis
Iyis Moment of inertia about Y -axis
ryis Radius of gyration about Y -axis
Syis Elastic section modulus about Y -axis
Cwis Warping constant
h0is Distance between centroid of flanges
J is Torsional moment of inertia
For
From the below given figure in the textbook,
For the y axis, since the shape is compact, there is no flange local buckling
Check the upper limit:
Roof load: Combination 3 controls
where, D is dead load and S is snow load
Tributary width =
Purlin load =
Component normal to roof =
Component parallel to roof =
Calculate factored bending moment about x axis and y axis
Use ½ of weak - axis bending strength in the interaction equation:
Conclusion:
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Chapter 5 Solutions
Steel Design (Activate Learning with these NEW titles from Engineering!)
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