Material Properties Flashcards
7 cards from real ASCE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Material Properties flashcards as text
Using G = E / [2(1 + ν)], what is the approximate shear modulus of structural steel?
Answer: 11,200 ksi
With E = 29,000 ksi and ν = 0.3, G = 29,000 / 2.6 ≈ 11,200 ksi.
How is the yield strength of a metal with no clear yield point, such as high-strength steel or aluminum, usually determined?
Answer: By the 0.2% offset method
Draw a line parallel to the elastic slope, offset by 0.002 strain; the stress where it crosses the curve is the yield strength.
Which material usually behaves in a brittle way, failing with little plastic deformation?
Answer: Gray cast iron
Gray cast iron fractures with very little elongation, and its compressive strength is much higher than its tensile strength.
On a mild-steel stress-strain curve, which region comes right after the yield plateau, where stress rises again with more strain?
Answer: Strain-hardening region
After the yield plateau, dislocation interactions raise the steel's resistance until it reaches ultimate strength.
In the Superpave performance grade PG 64-22, what do the numbers mean?
Answer: Reliable performance from a high pavement temperature of 64°C down to a low of −22°C
PG binders are graded by the high and low pavement temperatures, in °C, at which they meet the performance requirements.
About what fraction of its compressive strength is the direct tensile strength of normal concrete?
Answer: About 10%
Concrete's tensile strength is only about 8–15% of its compressive strength, so reinforcement carries the tension.
What maximum usable compressive strain at the extreme concrete fiber does ACI 318 assume for flexural strength design?
Answer: 0.003
ACI 318 sets the maximum usable compressive strain at the extreme fiber to 0.003.