Material Specifications Flashcards
7 cards from real NETTCP 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 Specifications flashcards as text
Which AASHTO soil classification group is generally considered unsuitable as a subgrade material without treatment?
Answer: A-7-6
A-7-6 soils are highly plastic clays with poor load-bearing characteristics and are generally unsuitable as subgrade without stabilization or replacement.
For structural steel used in highway bridges, which ASTM grade is most commonly specified for rolled W-shapes?
Answer: ASTM A709 Grade 50
ASTM A709 Grade 50 is the bridge-specific structural steel specification most commonly used for rolled W-shapes in highway bridges.
What is the purpose of specifying a maximum water-to-cementitious-material (w/cm) ratio in bridge concrete?
Answer: To limit permeability and improve durability against chloride intrusion
A lower w/cm ratio reduces concrete permeability, limiting chloride ion penetration and protecting reinforcing steel from corrosion.
According to AASHTO M 29, what is the standard specification for fine aggregate (sand) used in bituminous mixtures?
Answer: It covers natural sand, manufactured sand, and screenings meeting specific gradation and quality requirements
AASHTO M 29 covers fine aggregate from natural or manufactured sources used in asphalt mixtures, including gradation and quality limits.
Fly ash used as a supplementary cementitious material in concrete must conform to which ASTM standard?
Answer: ASTM C618
ASTM C618 specifies requirements for natural pozzolans and fly ash used as supplementary cementitious materials in concrete.
For highway guardrail, which ASTM specification covers the W-beam rail element material?
Answer: ASTM A36 or A572
W-beam guardrail is fabricated from steel meeting ASTM A36 or A572 requirements for structural carbon steel.
What characteristic distinguishes a Superpave SP-12.5 mix designation from an SP-19 mix?
Answer: SP-12.5 has a nominal maximum aggregate size of 12.5 mm versus 19 mm for SP-19
The number in a Superpave mix designation (SP-12.5, SP-19) refers to the nominal maximum aggregate size in millimeters.