Engineering Geology Flashcards
7 cards from real ASBOG practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Engineering Geology flashcards as text
The Seed-Idriss simplified procedure for evaluating liquefaction potential uses which two key parameters derived from SPT data?
Answer: Cyclic Stress Ratio (CSR) and Cyclic Resistance Ratio (CRR)
The simplified procedure compares the CSR imposed by the earthquake to the CRR of the soil (derived from corrected SPT blow counts) to determine the factor of safety against liquefaction.
Which type of landslide is characterized by a curved, concave-up failure surface and backward rotation of the slide mass?
Answer: Rotational slide (slump)
A rotational slide (slump) moves along a spoon-shaped, concave-up failure surface, causing the head of the slide to tilt backward relative to the original slope.
Schmidt hammer rebound values are used in engineering geology primarily to estimate:
Answer: Uniaxial compressive strength of intact rock
The Schmidt hammer measures surface rebound, which correlates empirically with the uniaxial compressive strength (UCS) and Young's modulus of intact rock.
Which process is primarily responsible for creating a glacial U-shaped valley?
Answer: Glacial abrasion and plucking widening valley walls
Glacial ice erodes valley walls and floor by abrasion and plucking, transforming the original V-shaped stream valley into a characteristic U-shaped trough.
The 'rock bolt factor of safety' in a tunneling context is typically defined as the ratio of:
Answer: Pull-out capacity to applied load on the bolt
The factor of safety for a rock bolt equals the ultimate pull-out resistance (from grout bond and anchor) divided by the actual tensile load the bolt must carry.
Which sedimentary structure is the most reliable indicator of the original 'way-up' (younging direction) in deformed strata?
Answer: Graded bedding
Graded bedding shows coarse grains at the base grading to fine grains at the top of each bed, reliably indicating the up direction at the time of deposition.
During a geotechnical site investigation for a dam foundation on a river, which condition would most require detailed evaluation of internal erosion (piping) potential?
Answer: Heterogeneous alluvial deposits with contrasting permeability layers
Heterogeneous alluvium with adjacent high- and low-permeability layers creates preferential seepage paths where hydraulic gradients can concentrate and progressively erode fine particles (piping).