Paper format. Professional Engineers Ontario /
Engineers Canada National Examinations, December 2014 — 98-Civ-B3 Geotechnical
Design. Three hours, OPEN BOOK, any non-communicating calculator. Section A carries five
discussion questions of 7 marks each (answer any four); Section B carries five design
questions of 24 marks each (answer any three); the examinable total is
4 × 7 + 3 × 24 = 100 marks. All ten questions are worked below, because the
set is a study resource rather than a timed attempt.
Reference texts (98-Civ-B3 / 16-Civ-B3 Geotechnical Design).
- B. M. Das, Principles of Foundation Engineering, 9th ed. — bearing
capacity (Ch. 3), stress increase in a soil mass (Ch. 6), retaining walls (Ch. 8), pile
foundations (Ch. 11).
- B. M. Das, Principles of Geotechnical Engineering, 9th ed. — lateral
earth pressure (Ch. 13), shear strength (Ch. 12), slope stability (Ch. 15), subsurface
exploration (Ch. 17).
- Canadian Geotechnical Society, Canadian Foundation Engineering Manual
(CFEM), 4th ed. — the governing Canadian practice document for site investigation,
bearing resistance, deep foundations and earth-retaining structures.
- R. F. Craig, Craig's Soil Mechanics, 8th ed. — earth pressure theory
and slope stability.
- D. P. Coduto, Foundation Design: Principles and Practices, 2nd ed. —
in-situ testing and SPT correlations.
- J. E. Bowles, Foundation Analysis and Design, 5th ed. — bearing
capacity factors and retaining-wall stability tables.
Sources of charts and assumed values (page-1 Note 6). Note 6 of this
paper requires the candidate to identify the source of every design chart and every
assumed value. Each chart reading and each assumption below is therefore named where it is
used, and the values assumed in the absence of data are collected here:
- Q6 — adhesion factor α from Das,
Principles of Foundation Engineering, Table 11.6 (Terzaghi, Peck & Mesri
form, α against $c_u/p_a$); $\lambda$ from Vijayvergiya & Focht
(1972) as tabulated by Das, Table 11.7.
- Q7 — overburden correction $C_N$ from Liao & Whitman
(1986); $\phi'$ from Wolff (1989) and from Hatanaka & Uchida (1996), both reproduced
in Das, Ch. 2; settlement-controlled bearing pressure from Meyerhof (1965) as given by
Das, Ch. 5, used only as a serviceability check because the question forbids direct
correlations of bearing capacity to penetration index. Table I prints the blow counts as
field values $N_f$; with no hammer data they are converted as $N_{60} = N_f$, i.e. a
safety hammer at the reference 60 per cent energy ratio with borehole, sampler and
rod-length factors of 1 (Das, Ch. 2, hammer-efficiency and correction-factor tables).
- Q8 — embankment influence factor from Osterberg (1957),
reproduced as Das Fig. 6.24; the closed form of that chart is used so the reading carries
no chart-scaling error.
- Q9 — Meyerhof general bearing-capacity equation with the shape
factors of De Beer (1970) and the depth factors of Hansen (1970), as set out in Das,
Ch. 3.
- Q10 — Coulomb active earth-pressure coefficient, Das
Eq. 13.31; unit weight of the mass-concrete wall assumed
$\gamma_c = 24\ \text{kN/m}^3$ (CFEM 4th ed., normal-density concrete), the only value
the figure does not supply.
