
Concept explainers
The most economical section using LRFD and ASD.

Answer to Problem 9.1PFS
The safe designed section is
Explanation of Solution
Given Information:
LRFD:
The design load is
The design moment is
Assuming self weight as 0.1 k/ft.
The moment due to self weight is
The total design moment is
The design strength of beam is
Taking
The required section modulus is
Selecting the section such that Z>Zrequired
The plastic section modulus is 283 in.3
ASD:
The design load is
Assuming self weight as 0.1 k/ft.
The total design load is
The design moment is
The design strength of beam is
The required section modulus is
Selecting the section from AISC manual such that Z>Zrequired
Conclusion:
Select
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Chapter 9 Solutions
Structural Steel Design (6th Edition)
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