Lab Testing Procedures 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 Lab Testing Procedures flashcards as text
A nuclear density gauge used for field compaction testing must be licensed under which U.S. federal agency because it contains radioactive material?
Answer: NRC (Nuclear Regulatory Commission)
Nuclear density gauges contain radioactive sources (Cesium-137 and Americium-241/Beryllium) and are regulated by the NRC or agreement states.
In the Superpave gyratory compactor (SGC), what parameter is adjusted to simulate field compaction effort at different design levels?
Answer: Number of gyrations (Ndesign)
Ndesign is the number of gyrations used to compact asphalt specimens and is selected based on design traffic level (ESALs).
Per AASHTO T 166, the bulk specific gravity of a compacted asphalt mixture specimen is determined using:
Answer: Saturated surface dry (SSD) weighing in air and submerged in water
Gmb is calculated from the dry mass, the SSD mass, and the submerged mass in water using Archimedes' principle.
The California Bearing Ratio (CBR) test measures the strength of a subgrade soil relative to:
Answer: A standard crushed limestone base material
CBR expresses the penetration resistance of the test material as a percentage of the resistance of a standard well-graded crushed limestone.
When splitting a bulk aggregate sample using a riffle splitter (sample splitter), the correct technique is to:
Answer: Feed material uniformly across all chutes at a controlled rate
Material must be fed uniformly across the full width of the splitter to ensure each half is a representative portion of the original sample.
In a concrete compressive strength test per AASHTO T 22, cylinders are capped or ground to ensure the end surfaces are perpendicular to within:
Answer: 0.5 degrees
End surfaces must be perpendicular to the axis within 0.5° and plane within 0.002 inches to ensure uniform load distribution during testing.
The sand equivalent test (AASHTO T 176) is used to measure the proportion of:
Answer: Fine dust and clay-like material in fine aggregate
The sand equivalent value indicates the relative proportion of fine dust or clay-like material in fine aggregate — a higher value means cleaner aggregate.