becomes necessary to construct a field p-e curve

∆H =

simulating consolidation in the field. These constructions

e1 - e2

(5-1)

H

are also shown in figure 3-7. They are based on the

1 + e0

assumption that the straight lower branch of the field p-e

where

curve, K, intersects the laboratory curve at e = 0.4e0.

e1, e2

=

initial and final void ratios,

Furthermore, the field curve must pass through point a,

respectively,

from the field

corresponding to the present overburden pressure and

pressure-void

curves,

the natural void ratio. The field compression index, Cc, is

corresponding to the initial and

taken as the slope of the straight lower branch of K on

final

effective

foundation

the semilogarithmic diagram.

pressures

eo

=

average initial void of the stratum

a. Settlement computations.

The total

H

=

total thickness of the compressible

settlement, ∆H, of a foundation stratum is computed

stratum This formula also may be

used to estimate foundation

according to the following formula:

rebound due to excavation. When

the lower portion of

Figure 5-3. Influence value for vertical stress under a uniformly loaded circular area.

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