What is rock anisotropy (without respect to the properties of

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CEE 437 Engineering Geology I
Final Exam, June 11,2002
Instructions: This final exam will be given 4:30-6:20 p.m. Tuesday, Jun. 11, 2002. The exam will be
closed book, but feel free to discuss the questions with anyone including the instructors through June
10th. Answers to e-mailed questions will be e-mailed to all students.
Each of the questions below should take no more than 10 to 15 minutes to answer. Concise, brief answers
are encouraged - grading will be based on an indication of comprehension of the material.
1. How do fractures effect rock strength, deformability, and anisotropy? Estimate the range of rock
mass modulus for RMR values of 10,50, and 90. Compare Hoek-Brown, Barton-Bandis, and MohrCoulomb strength envelopes for intact rock and rock with a fracture frequency of 30/meter. (15
points)
2. Define Mode 1, Mode 2, Mode 3 fractures, and stylolites. Discuss the difference between different
types of fractures for their effect on groundwater flow and transport, foundation deformability, and
slope stability. (10 points)
3. Describe the difference between the Terzaghi (1964) and Mauldon&Mauldon(1997) corrections for
fracture orientation bias. (5 points)
4. Describe the pattern of fracturing which occurs in a fold – how is the fracturing different at the crest,
flank, and base. Where do Mode 1 fractures occur, and where do Mode 2 fractures occur ? What are
their orientations? (5 points)
5. Define the possible slope failure modes in intensely fractured rock, rock with a single extensive
fracture system, and rock with three fracture systems. Describe the effect of groundwater, fracture
orientation, fracture roughness, and infilling on failure modes. (10 points)
6. Draw a landslide zone, illustrating the occurrence of different types of fractures, scarps, and talus.
What signs would indicate incipient slope instability? What signs would indicate a historical slide ?
What instrumentation can be used to monitor slope movement? (10 points)
7. Define P, S, and Surface waves. How are these waves used to calculate earthquake epicenter
location, magnitude, and possible engineering impacts from earthquakes. Discuss the transfer of
seismic waves through a layered geology consisting of a soft fractured rock overlain by a stiff, overconsolidated sediment, with organic soils at the surface. (10 points)
8. Describe the geologic settings that would occur in the vicinity of a recent volcano – both soils and
rock. (10 points)
9. Draw of typical Puget Sound glacial geologic setting, illustrating the glacial facies and their
engineering significance. Describe the grain size distribution, grading, heterogeneity and relative
density of these facies. (10 points)
10. Prepare a table comparing constituents (e.g., clay, silt, sand, gravel), density, anisotropy,
heterogeneity, sensitivity, and strength of the following soil deposits: alluvium, colluvium, lacustrine
sediments, glacial sediments, aeolian sediments, marine sediments, pedogenic soils, and organic soils.
(15 points)
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