Date 25/02/2013
UND-MEMO-02-010
Email:
s 9(2)(a)
To
s 9(2)(a)
s 9(2)(a)
From
CC
s 9(2)(a)
THE ACT
Date
25/02/2013
Subject
Detailed Design Geotechnical Parameter Selection – Revision
R E C O M M E N D E D D E T A I L E D D E S I G N P A R A M E T E R S
We have completed a review of geotechnical material strength parameters, and recommend
minor changes to previous recommendations. The recommended material parameters are
presented in table 1 below.
The revised parameters will be carried through to the next revision of the geotechnical interpretive
report following a review of the stiffness parameters that is currently underway.
Table 1: Recommended Design Parameters
Geological Units
Holocene
Completely
Design Parameters
Pleistocene Residual
Fill
Alluvium
Organic
Weathered
Layers
Alluvium
Soil
East
West
Greywacke
INFORMATION
Unit
kN/m3
19
18
18
16.5
18
18
19.5
Weight
Mid1)
32
32
28
35
34
36
Friction
°
Angle
Lower2)
28
30
28
26
32
32
35
RELEASED UNDER
Mid1)
6
6
2
10
10
15
Cohesion (KPa) Lower2)
4
4
4
0
4
4
10
Poisson’s
-
0.3
0.3
0.3
0.35
0.3
-
0.3
Ratio
Notes:
1) Based on laboratory testing, analysis of CPT data and SPT-N value plots
2) Based on analysis of CPT data and SPT-N value plots
OFFICIAL
Memorial Park Alliance / Memorandum / 25.02.13
2
B A C K G R O U N D
Initial design parameters were used in the concept TCE design package. These parameters were
based on the site investigation data available at the time including limited laboratory testing.
Since the TCE design submission further site investigation, laboratory testing and construction works
have been completed. This has provided a more extensive understanding of the geotechnical
materials and their parameters. As such, it is appropriate to revise the initial parameters and
conduct a more intensive analysis of the site investigation data received up to February 2013.
D E S I G N P A R A M E T E R D I S C U S S I O N
A design parameter workshop was held to establish revised detailed design parameters. Within this
workshop, the analysis of the site investigation data was presented then compared to site
observations and local project knowledge.
THE ACT
Design parameters are determined from a combination of:
•
Analysis of CPT data
•
Plotting of SPT-N values
•
Laboratory testing
•
Local geotechnical knowledge and project experience
•
Site observations of materials during initial construction and site investigation
Where available, laboratory testing has been given heavier weighting in the assessment than less
direct interpolation from the CPT and N value analysis.
Annotated graphical outputs of the CPT and SPT-N value analysis and relevant laboratory testing
results are enclosed in the Appendix.
Analysis of the stiffness parameters is underway.
A P P E N D I C I E S
INFORMATION
UND West Alluvium CPT Geological Layers
UND West Alluvium CPT Material Behaviour
UND East Alluvium CPT Geological Layers
UND East Alluvium CPT Material Behaviour
UND Rock CPT Geological Layers
RELEASED UNDER
UND Rock CPT Material Behaviour
Borehole SPT N Values
Borehole Materials SPT N Values
Laboratory Testing to 14.02.2013
OFFICIAL