Paper format. National Exams, December 2018 —
16-Civ-B19 Foundation Engineering. Three hours, OPEN BOOK (one textbook plus one
hand-written 8.5″ × 11″ aid sheet, both sides). Five questions, all to be
answered, all of equal weight (20 marks each, 100 marks total). Any non-communicating
calculator is permitted. The paper mixes SI and US customary units question by question,
so each answer below stays in the units the question is posed in.
Reference texts
- Das, B.M., Principles of Foundation Engineering, 9th ed. — the standard
text for this syllabus. Ch. 3 (ultimate bearing capacity), Ch. 5 (vertical stress
increase in soil), Ch. 6 (shallow-foundation settlement and plate load tests),
Ch. 7 (mat foundations), Ch. 9 (pile foundations) and Ch. 10 (pile groups)
supply every method used here.
- Das, B.M., Principles of Geotechnical Engineering, 9th ed. — effective
stress, consolidation and the Boussinesq stress-distribution theory the above builds on.
- Canadian Geotechnical Society, Canadian Foundation Engineering Manual (CFEM),
4th ed., 2006 — the Canadian practice document: limit-states terminology, geotechnical
resistance factors, settlement tolerances and pile design guidance.
- National Building Code of Canada (NBCC) 2020, Part 4 — load
combinations and the limit-states framework within which the CFEM resistance factors sit.
- Bowles, J.E., Foundation Analysis and Design, 5th ed. — alternative
bearing-capacity and settlement formulations, useful as a cross-check.
Check: three conflicts in the printed
paper, resolved as follows.
- Q.2(a) embankment dimensions. The top of the figure reads
14 m + 5 m + 14 m = 33 m and the bottom chain reads
5 m + 11.5 m + 16.5 m = 33 m, so the two are consistent:
A2 lies 5 m inside the left toe and A1 lies
16.5 m from each toe, i.e. on the embankment centreline.
- Q.4(b) undrained shear strength. The paper prints
cu = 18 250 lb/ft². That is about 874 kPa — an order
of magnitude stronger than any normal saturated clay and at the clay/weak-rock boundary.
The answer below uses the printed value, and also states the result for
cu = 1 825 lb/ft² (87 kPa, a very stiff clay) in case the
extra digit is a typographical slip.
- Q.4(c) mat dimensions. The text says 75 ft × 100 ft
while the figure it refers to is labelled 90 ft × 120 ft. The figure is
solved as the primary case (the question says “as shown in figure below”) and
the 75 ft × 100 ft case is carried through in full alongside it, so either
reading is answered.
