Steel Design
Study online at https://quizlet.com/_iu09aj
1. a) In about 1 sentence, explain why the flange is typically thicker than the web
of a W-Shape steel member.: More material farther from the centroid causes a larger moment of inertia
which leads to more resilience against bending moments.
2. b) In about 1 to 2 sentences, explain why stockier sections are typically
used as compression members, whereas deeper sections are typically used for
beams.: Stocky sections are used as compression members because the strong and weak axis of inertia are similar
giving it similar strength about both axis. Deeper sections are used for beams because it gives it a larger strong axis
moment of inertia
3. c) Which grade of steel would have higher ductility: A514 quenched and
tempered allow steel OR A36 steel? Why?: A36, because A514 is quenched giving it higher strength
and making it more brittle.
4. d) Relate the yield strength of steel in shear to its yield strength in tension?: -
yield shear strength is about .6 yield strength in tension (per AISC)
5. e) Structural engineers must ensure the strength, stiffness, and reliability of
building structures. Provide brief (no more than 1 sentence) definitions for each
of these three terms.: Strength-ability for a member to resist forces
stiffness-low deformations with applied loads
reliability- designed with low probablity of failure
6. f) In about 1 to 2 sentences, explain the key similarities and differences
between Allowable Stress Design (ASD) and Load and Resistance Factor Design
(LRFD).: ASD relies on 1 safety factor to account for uncertainty in load and resiliance, and represents worst case
loads.
LRFD relies on amplified load combinations that account for load uncertainty and it reduces the members strength to
account for resistance uncertainty. LRFD loads are amplified and not the actual worst case.
7. g) List 3 reasons why it is not possible to accurately predict the failure of
structural steel components in a building. (Hine: List reasons why we include
safety or resistance factors in our design).: 1.) Material Strength Variations
2.) loads are unpredictable and not on center
3.) Stresses introduced during fabrication and erection
8. h) List 3 strength limit states of a steel tension member.: Tensile yield
Tensile rupture
Tensile block shear rupture
1/3
Study online at https://quizlet.com/_iu09aj
1. a) In about 1 sentence, explain why the flange is typically thicker than the web
of a W-Shape steel member.: More material farther from the centroid causes a larger moment of inertia
which leads to more resilience against bending moments.
2. b) In about 1 to 2 sentences, explain why stockier sections are typically
used as compression members, whereas deeper sections are typically used for
beams.: Stocky sections are used as compression members because the strong and weak axis of inertia are similar
giving it similar strength about both axis. Deeper sections are used for beams because it gives it a larger strong axis
moment of inertia
3. c) Which grade of steel would have higher ductility: A514 quenched and
tempered allow steel OR A36 steel? Why?: A36, because A514 is quenched giving it higher strength
and making it more brittle.
4. d) Relate the yield strength of steel in shear to its yield strength in tension?: -
yield shear strength is about .6 yield strength in tension (per AISC)
5. e) Structural engineers must ensure the strength, stiffness, and reliability of
building structures. Provide brief (no more than 1 sentence) definitions for each
of these three terms.: Strength-ability for a member to resist forces
stiffness-low deformations with applied loads
reliability- designed with low probablity of failure
6. f) In about 1 to 2 sentences, explain the key similarities and differences
between Allowable Stress Design (ASD) and Load and Resistance Factor Design
(LRFD).: ASD relies on 1 safety factor to account for uncertainty in load and resiliance, and represents worst case
loads.
LRFD relies on amplified load combinations that account for load uncertainty and it reduces the members strength to
account for resistance uncertainty. LRFD loads are amplified and not the actual worst case.
7. g) List 3 reasons why it is not possible to accurately predict the failure of
structural steel components in a building. (Hine: List reasons why we include
safety or resistance factors in our design).: 1.) Material Strength Variations
2.) loads are unpredictable and not on center
3.) Stresses introduced during fabrication and erection
8. h) List 3 strength limit states of a steel tension member.: Tensile yield
Tensile rupture
Tensile block shear rupture
1/3
