This preview shows pages 1–3. Sign up to view the full content.
ρ
9
•
Review of Consolidation (Oedometer) Test
o
Objective to determine the following parameters:
1.
C
C
= 
Δ
e /
Δ
log
σ
’
V
= 
Δ
e / log (p
2
/p
1
)
2.
C
R
= 
Δ
e /
Δ
log
σ
’
V
= 
Δ
e / log (p
2
/p
1
)
= C
e
(e
xpansion) = C
S
(s
well )
3.
σ
’
C
= p
C
(F / L
2
)
4.
c
v
= T (H/N)
2
/ t
(L
2
/ T)
5.
C
α
= 
Δ
e /
Δ
log t = 
Δ
e / log (t
2
/t
1
)
o
Onedimensional (constrained) test:
measure 1D deflection under vertical load
o
Test Procedure:
1. Prepare and saturate soil specimen, typical height H=1” and diameter=2.5”.
2. Apply load increment
Δ
p every 24 hrs following geometric progression,
e.g. ¼, ½, 1, 2, 4, 8, 16, 32 tsf
Note: Both the load sequence and duration of loading affect the results.
3. Read dial gage deflection R for each load following
≈
geometric progression,
e.g. ¼, ½, 1, 2, 4, 8, 15, 30, 60, 120, 240, 480, 720, 1440 min
Rigid Ring
Soil Specimen
Load,
Δσ
’
V
or p
Porous Stone
Porous Stone
Dial Gage Reading, R
Water Bath
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document ρ
10
4. Plot dial gage readings R vs. log time for each load and fit a smooth curve for analysis.
Calculate C
v
and C
α
using the Casagrande construction:
a) Find R
0
: choose t
1
, calculate t
2
= t
1
/4, measure vertical distance “a” on curve from
t
1
to
t
2
, R
This is the end of the preview. Sign up
to
access the rest of the document.
This note was uploaded on 09/12/2011 for the course CEG 4012 taught by Professor Staff during the Fall '08 term at University of Florida.
 Fall '08
 Staff

Click to edit the document details