Geotechnical Engineering

DHARM

250 GEOTECHNICAL ENGINEERING

7.3. Define ‘preconsolidation pressure’. In what ways in its determination important in soil engineer-
ing practice? Describe a suitable procedure for determining the preconsolidation pressure.
(S.V.U.—B.Tech., (Part-time) Apr., 1982 & Sep., 1982, B.E. (R.R.)—May, 1975)
7.4. Explain with neat sketches:
(i) The influence of load-increment ratio on time-settlement curve.
(ii) Terzaghi’s assumptions. (S.V.U.—B.Tech., (Part-time)—Apr., 1982)
7.5. Differentiate between ‘compaction’ and ‘consolidation’.
(S.V.U.—B. Tech., (Part-time)—June, 1981, B.E., (R.R.).—Feb., 1976)
7.6. (a) Define (i) Compression Index, (ii) Coefficient of volume decrease, (iii) Coefficient of consoli-
dation and (iv) Per cent consolidation. (S.V.U.—B.Tech., (Part-time)—June, 1981)
(b) Describe a suitable method of determining the compression index of a soil.
(S.V.U.—B.Tech., (Part-time)—June, 1981, B.E., (R.R.)—Nov., 1973)
7.7. Explain what is meant by normally consolidated clay stratum and over-consolidated clay stra-
tum. Sketch typical results of consolidation test data to a suitable plot relating the void ratio and
consolidation pressure in each case and show how preconsolidation can be estimated.
(S.V.U.—B.E., (R.R.)—Sep., 1978)
7.8. (a) Distinguish between normally consolidated and over consolidated soils.
(b) Explain in detail and one method for determining the coefficient of consolidation of a soil.
(S.V.U.—B.E., (R.R.)—Feb., 1976, Nov., 1973)
7.9. Obtain the differential equation defining the one-dimensional consolidation as given by Terzaghi,
listing the various assumptions. (S.V.U.—B.E., (R.R.)—May, 1975, Nov., 1974,
Nov., 1973, May, 1971, Dec., 1970, Nov., 1969)
7.10. Define and distinguish between coefficient of volume compressibility and coefficient of consoli-
dation.
Describe clearly one method of computing coefficient of consolidation, given oedometer test data.
(S.V.U.—B.E., (R.R.)—Nov., 1973)
7.11. (a) Draw a typical time-consolidation curve for an increment of load and show the process of
consolidation.
(b) Explain why is it necessary to double the load in a consolidation test.
(S.V.U.—B.E., (R.R.)—May, 1970, B.E., (N.R.)—May, 1969)
7.12. Explain with suitable analogy Terzaghi’s theory of one-dimensional consolidation of soils.
(S.V.U.—B.E., (R.R.)—Dec., 1968)
7.13. (a) Derive the expression for the total settlement of a normally consolidated saturated clay sub-
jected to an additional pressure.
(b) Indicate the nature of e-log σ curve that is got in a laboratory test on (i) undisturbed nor-
mally consolidated clay, (ii) Undisturbed overconsolidated clay.
(S.V.U.—B.E., (N.R.)—Sep. 1968)

7.14. Derive the equation ∆H = H C
e

pp

i p

c

()

log ()

1 0 10

0

+ 0

+

z

∆ for consolidation of clays.

(S.V.U.—B.E., (R.R.)—May, 1969)
7.15. Explain “Secondary Consolidation”. (S.V.U.—B.E., (R.R.)—May, 1970, May, 1971
Four year B.Tech.—June, 1982)