Interpretive Geotechnical Report for
Clifton
Garage
Investigation
April 2015
Geotechnical
REF: JG0012/2015/04/2565
Paarl Mountain Slip Geotechnical Investigation
Interpretive Geotechnical Report
SMEC REPORT
QUALITY ASSURANCE ISSUE DATA
Report Title: Interpretive Report for Clifton Garage Geotechnical Investigation
Client: City of Cape Town Metropolitan Municipality
Project Name: Clifton Garage Geotechnical Investigation
Report Number: JG0012/2015/04/2565
Revision Number Final v.01
Revision History:
2015-03-20
2015-04-16 Issued to Report
Status Date Draft
Interpretive
Report
Final
Interpretive
Report Written by Reviewed/Approved by Name
Ryan Freese
Pr. Sci. Nat.
MSc (Engineering &
Environmental Geology)
Professional Geologist
Fernando Pequenino
Pr. Eng.
BEng Hons (geotechnical)
Section Manager
Written by: 2015/04/16 Signed Date 2015/04/16 Signed Date Approved by: SMEC | SOUTH AFRICA | GEOTECHNICAL Neil Eybers
Institution City of Cape
Town
Metropolitan
Municipality
Paarl Mountain Slip Geotechnical Investigation
Interpretive Geotechnical Report
TABLE OF CONTENTS Page No 1. INTRODUCTION AND TERMS OF REFERENCE ......................................................... 1 1.1 1.2 1.3 1.4 1.5 Scope ..................................................................................................................................................... 1 Terms of Appointment........................................................................................................................... 1 Aims and Methodology .......................................................................................................................... 1 Information Sources .............................................................................................................................. 2 Limitations of Assessment ..................................................................................................................... 2 2. LOCATION AND SITE DESCRIPTION ........................................................................ 3 3. GEOLOGY .............................................................................................................. 4 4. SITE INVESTIGATION ............................................................................................. 5 4.1 4.2 4.3 4.4 4.5 4.6 Test Pits .................................................................................................................................................. 5 Rotary Core Boreholes ........................................................................................................................... 5 Electrical Resistivity Survey ..................................................................... Error! Bookmark not defined. Laboratory Testing ................................................................................................................................. 6 Electrical Resistivity Survey .................................................................................................................... 8 Borehole Pump Tests ............................................................................................................................. 9 5. GENERAL ASSESSMENT OF THE GEOTECHNICAL CONDITIONS ............................... 9 5.1 5.2 5.3 Engineering and Geological Ground Units ............................................................................................. 9 5.1.1 Fill Soils .................................................................................. Error! Bookmark not defined. 5.1.2 Residual Granitic Soils ......................................................................................................... 10 5.1.3 Granite Bedrock .................................................................................................................. 11 Groundwater ....................................................................................................................................... 11 Expansive, Dispersive and Collapsible Soils ......................................................................................... 12 6. GEOTECHNICAL ANALYSIS ................................................................................... 13 6.1 6.2 Bulk Earthworks ................................................................................................................................... 13 6.1.1 Excavation Conditions ......................................................................................................... 13 6.1.2 Geotechnical Analysis Parameters ...................................................................................... 14 Foundation Conditions ........................................................................................................................ 15 7. CONCLUSIONS AND RECCOMENDATIONS ........................................................... 15 8. REFERENCES ........................................................................................................ 17 9. CLOSING .............................................................................................................. 17 SMEC | SOUTH AFRICA | GEOTECHNICAL Paarl Mountain Slip Geotechnical Investigation
Interpretive Geotechnical Report
APPENDIX A: SITE PLANS APPENDIX B: TEST PIT PROFILES AND PHOTOGRAPHS APPENDIX C: BOREHOLE LOGS AND PHOTOGRAPHS APPENDIX D: DRILLER’S LOGS APPENDIX E: LABORATORY TEST RESULTS APPENDIX F: ELECTRICAL RESISTIVITY SURVEY RESULTS APPENDIX G: BOREHOLE PUMP TEST RESULTS APPENDIX H: SITE CROSS‐SECTIONS SMEC | SOUTH AFRICA | GEOTECHNICAL Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
1.
INTRODUCTION AND TERMS OF REFERENCE 1.1
Scope
This interpretive report presents the findings of a geotechnical investigation for the proposed
Clifton Garage “Redevelopment Precinct”. The proposed project is approximately 3000m² in
extent consisting of a 3 level underground parking facility, a retail facility, together with shops
and a restaurant.
The investigation was carried out in accordance with the scope of work provided by the client,
to determine whether the development is feasible and to obtain the relevant ground
parameters for use in design of the development. Particular emphasis has been placed on
assessing the stability of the proposed cut on the eastern side of the development and
producing ground parameters for the design of stabilisation methods for this cut.
1.2
Terms of Appointment
SMEC South Africa was initially appointed to undertake the geotechnical investigation on the
11th of December 2014 according to the SMEC quote Q818. A site walk over took place on
the 21st of January 2015; at the meeting a number of issues became apparent in terms of
access to the majority of the site. As such the scope of the investigation was amended and an
extension to the contract was compiled to include the amended scope. SMEC South Africa
was appointed under the variation order on the 27th February 2015.
1.3
Aims and Methodology
The following methodology was adopted to realise the aims of the study:

Desktop study including the review of available geological, topographical and
hydrological maps, site plans, plans of the proposed development and reports and
literature for the proposed infrastructure on underlying geology. (Stage 1)

Undertaking of a geotechnical investigation fieldwork.
o
Excavation of test pits across the site, to profile the surficial soils and take
representative soil samples. (Stage 2)
o
Drilling of rotary core boreholes to profile materials to beneath the
proposed development and sample materials at depth. (Stage 3)
o
Electrical resistivity to provide a wider indication of underlying conditions to
depth between borehole positions.

Analysis and reporting of the results obtained during the desktop study and
investigation, with regard to the bearing capacity of the founding horizons,
anticipated settlement, excavatibility, depth of ground water and cut slope
stability. (Stage 4)
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1.4
Information Sources
The following information sources were consulted and made available;
1.5

Topographical Map, Sheet 3318CD at a scale of 1 : 50 000.

Geological Map, Sheet 3318CD Cape Town at a scale of 1 : 50 000.

Published technical references (listed in Section 8 of this report).

Unnamed aerial plan of proposed development (contained in Appendix A).

Unnamed cross-section of proposed development (contained in Appendix A).
Limitations of Assessment
The investigation comprised testing at a limited number of positions and is not likely to reveal
the detail of the conditions that will become evident during construction. It is thus imperative
that a Competent Person inspects all excavations to ensure that conditions at variance with
those predicted do not occur and to undertake an interpretation of the facts supplied in this
report to apply to on-site conditions as exposed during development of the site.
It is possible that certain indications of ground contamination or ground water levels were
latent or otherwise not visible. Our opinions can only be based on what was visible at the time
the visit was conducted. This report has been prepared for the exclusive use of the client, with
specific application to the proposed project.
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2.
LOCATION AND SITE DESCRIPTION The site is situated to the west of Victoria Road (M6) in the Clifton suburb of Cape Town. The
northern part of the site consists of single storey parking garages with interstitial paved areas,
the majority of the site consists of bowls greens built on a cut-fill platform. The area has an
approximate gradient of 1V:7H and lies on the side slope of Lions Head Mountain,
approximately 150m from the Atlantic Ocean coastline. The site generally drains towards the
west. It ranges from 20-30m above mean sea level, and the proposed development will cover
an area of approximately 3000m².
According to the 1:1 500 000 Map Veld Types of South Africa (Acocks, 1975) the site falls
within the coastal fynbos veld type. Cape Town receives annual rainfall of 475mm. The
Weinert’s climatic N-value for the Clifton area is approximately 3.5, this implies that chemical
decomposition is the dominant mode of weathering and accounts for the deep weathering
profile observed during the investigation. With the exception of the northern and southern
areas, the vast majority of the site is inaccessible to any vehicles or plant.
The site location is at approximate co-ordinates S33.942953°and E18.375319°, indicated on
Diagram 2.1 below.
THE SITE Diagram 2.1: Site locality map
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3.
GEOLOGY The geological map of Cape Town (Sheet 3318CD, scale 1:50 000) indicates the site is
underlain by porphyritic and biotitic granite, with some fine grained and hybrid variants, the
granite is also intruded by multiple dolerite dykes in the area. The rock forms part of the Cape
Peninsula Pluton, of the Cape Granite Suite, which was formed by a number of large
magmatic intrusions into the Malmesbury Group sedimentary rocks. The granitic rock is
Namibian Aged dated to 600±20Ma.
Outcropping granite bedrock is visible close to the site, up slope from Victoria Road. The soils
on site are almost exclusively derived from the granite bedrock and predominantly comprise
of silty sands to gravelly sands. In most cases the transition from hard bedrock to residual soil
is virtually immediate, with very little weathered rock present between. Large granite boulders
(up to 6m³) were observed in the area, and where generally upslope of the site.
Figure 3.1: Geological Map 3318 Cape Town, site shaded in blue.
Site
Symbol
N-Cc
Stratigraphy
Lithology
Cape Peninsula Pluton, Mainly porphyritic and biotitic Granite with fine to
Cape Granite Suite
medium grained and hybridic variants
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4.
SITE INVESTIGATION The testing positions for the investigation are indicated in Figure 4.1.
4.1
Test Pits
A total of 4 test pits (CTP1-4) were excavated across the site on the 22nd of January 2015.
The test pits were excavated by hand to depths of 1.20-1.40m, refusal was not experienced in
any of the test pits. Heavy excavating machinery was not used to excavate the trial pits due to
access constraints over the majority of the site. The materials in the test pits were profiled,
photographed and representative samples retrieved for laboratory testing. The test pit profiles
and photographs are attached in Appendix B.
4.2
Rotary Core Boreholes
Six rotary core boreholes, CBH1-6 were drilled on the 2nd to 16th March 2015 to depths of
9.90-15.27m by Fairbrother Geotechnical Engineering cc, a specialist geotechnical drilling
contractor, using a HD300 DTH drill rig (CBH1 and 2), a dismantle-able LH75 drill rig (CBH3
and 4) and a HC6000 drill rig (CBH5 and 6).
The conditions at CBH3 and 4 are believed to be most critical as this is where the cut for the
development will be deepest and where water seepage in the adjacent existing retaining wall
was observed. The boreholes were drilled vertically, SPT’s (Standard Penetration Tests) were
undertaken in unconsolidated materials and Shelby tube samples were recovered at selected
positions where the consistency of the soils allowed for driving of the tube.
The borehole cores were profiled by our Engineering Geologists. The borehole logs (with SPT
results) and core photographs are attached in Appendix C. The driller’s logs are attached in
Appendix D.
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Figure 4.1: Site layout plan indicating testing positions.
Legend
CTP= test pit
CBH = borehole
4.3
Laboratory Testing
Laboratory tests were scheduled to confirm the on-site investigation and establish shear
strength parameters for the soils. Testing was undertaken by The University of Cape Town
Geotechnical Laboratory and our associated SANAS-accredited laboratory Soillab Western
Cape (Pty) Ltd. Tests were undertaken on representative disturbed and undisturbed samples
collected from site. The foundation indicator, consolidated undrained triaxial and rock test
results are summarised in Tables 4.1-4.3.
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Table 4.1: Indicator results (sieve analysis, hydrometer and Atterberg Limits).
Test
Depth
Position (m)
Origin
CTP1
0.7-1.3
Fill, derived from
residual granite
CTP4
0.741.28
Residual Granite
CBH2
5.0-6.0
Residual Granite
CBH3
5.507.50
Residual Granite
CBH4
5.505.90
Residual Granite
CBH6
3.0-4.5
Residual Granite
CBH6
7.0-7.95
Residual Granite
Clay
Silt
Sand Gravel LS
%
%
%
PI
%
Pot.
Uni.
Exp
Clas.
10.6
6
64
20
0.2
NP
Low
SP
11.8
17
46
25
9
18
Low
SC
7.2
17
40
36
5
12
Low
SC
3.9
11
49
37
5
10
Low
SCSM
55
12
N/A
8.1
N/A
SM
33
6
19
64
11
5
10
Low
SCSM
2.9
18
62
17
4
9
Low
SCSM
LS= Linear Shrinkage
PI= Plasticity Index
Pot. Exp.=Potential Expansiveness
Uni. Clas.=Unified Soil Classification
Table 4.2: Triaxial results (CU).
Testing
Depth
Position (m)
CBH4
5.50-5.90
Material
φ’ (°)
Sample Type
Silty Sand
φ’ = Effective Angle of Internal Friction
c’ (kPa)
Shelby Tube 30
Undisturbed
c’ = Effective Cohesion
26.4
Table 4.3: Rock sample testing.
Test
Hardness
Description
Average
Is(50)
Conservatively
Assessed
Mean UCS
(MPa)
RQD
(%)
Failure
Mode
Granite
Point
Load
Very hard
rock
3.5
82.4
94
N/A
9.40-9.80
Granite
Point
Load
Very hard
rock
3.1
73.0
100
N/A
BH3
11.0-11.30
Granite
Hard rock
N/A
29.7
78
Sliding
Shear
Failure
BH3
11.0011.30
Granite
Hard rock
1.2
28.3
78
N/A
Test
Positi
on
Depth of
Test (m)
Rock
Type
BH1
5.85-6.10
BH3
UCS
Point
Load
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Table 4.3: Rock sample testing.
Test
Positi
on
Depth of
Test (m)
Rock
Type
BH5
8.65-9.00
Granite
BH5
8.65-9.00
Granite
Test
Hardness
Description
Average
Is(50)
Conservatively
Assessed
Mean UCS
(MPa)
RQD
(%)
Failure
Mode
Point
Load
Very hard
rock
5.3
124.8
100
N/A
Very hard
rock
N/A
118.7
100
Sliding
Shear
Failure
UCS
Uniaxial compressive strength calculated from point load Is(50). Based on the point load data and UCS test results
an average correlation of UCS=23.55*Is(50) was calculated this was used for the correlation.
4.4
Electrical Resistivity Survey
The Electrical Resistivity (ER) survey was undertaken by a specialist geophysics contractor,
Engineering and Exploration Geophysical Services (E&EGS), on the 30th and 31st March
2015, and consisted of 6 ER traverses undertaken in the median between the bowls greens
at Glen Country Club. Due to the differential weathering which is a result of the texture and
chemistry of granite rock, literature and experience show that, granitic profiles are prone to a
number of geotechnical hazards, namely granite corestones and variable depth to bedrock.
Corestones and variable bedrock depth can lead to excavation difficulties/uncertainties and
the corestones are well documented in causing slope stability problems, particularly in the
Clifton area.
These geotechnical features are easily misinterpreted or not identified using the point
information gathered from boreholes and test pits, therefore geophysics was undertaken to
delineate conditions between borehole positions. The borehole logs were used to calibrate
the geophysical data. ER was chosen as the preferred method of investigation as this method
gives a good indication of corestone formation and bedrock depth. Furthermore this method
of was favoured as the least intrusive to the adjacent bowling greens and country club.
Another concern was the proximity of Victoria Road and resultant traffic which would cause
excessive noise for other geophysical techniques.
As was anticipated, on this geology, the ER results show a good contrast between low
resistivity materials interpreted as soils and high resistivity material interpreted as rock. The
traverses indicate that continuous bedrock is found at depths as shallow as 5m towards the
north and west of the site. Soils are found to much greater depth in the south and east of the
site grading into bedrock at depths in excess of 15m depth in places, with resistive pinnacles
of rock rising to shallow depths (up to approximately 5m below egl). Multiple resistive blocks
are found throughout the soil horizons, indicating the presence of corestones. These results
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indicate the residual soil horizon has abundant granitic corestones and that the depth to
bedrock is highly variable. The full ER results and report are attached as Appendix F.
4.5
Borehole Pump Tests
Due to the depth of the proposed excavations for the development and the observation of
heavy seepage through an existing retaining structure on site, borehole pump tests were
undertaken to give an indication of the problem. Two pump tests were undertaken, one each
at BH3 and BH4. Constant head pumping tests were undertaken, it was specified that these
be undertaken at a head of approximately 8m below egl (the envisaged maximum depth of
the development) in order to give an indication of the amount of seepage into the excavation.
In 7 hours the test at BH3 was carried out, with the initial ground water level of 4.56m pumped
to a depth of approximately 9m below egl. The inflow into the borehole at this depth was
measured to be approximately 2.08x10-5 m³/second. The ground water level in BH3
recovered to a depth of 5.12m in 3 hours after pumping was terminated.
In 6 hours the test at BH4 was only able to pump from the initial ground water level of 3.65m
down to approximately 5.5m depth, before the capacity of the pump was exceeded. The
measured inflow into the borehole, at this depth was 1.36x10-5 m³/second. The ground water
level in BH4 recovered to a depth of 3.66m in 4 hours after pumping was terminated.
These tests were carried out in permeable standpipe piezometers with an internal diameters
of 60mm. During both tests the ground water levels in the surrounding boreholes were
measured, but these levels were unaffected by the tests.
5.
GENERAL ASSESSMENT OF THE GEOTECHNICAL CONDITIONS An assessment of the geotechnical conditions, based on the test pits, boreholes, laboratory
results, on-site observations, DCP and SPT test results, is provided in Sections 5.1 to 5.4.
Three cross-sections indicating the materials and ground water level underlying the site are
attached as Appendix H. It must be noted that the cross-sections are largely based on
extrapolated and interpolated point information, and levels were estimated from observation,
no survey of the site was undertaken.
5.1
Engineering and Geological Ground Units
The material underlying the site consisted of broadly similar soil horizons over bedrock,
despite this the thickness of these horizons and depth to bedrock varied greatly across the
site; which is to be expected in a granitic profile. From egl the typical soil profile consisted of
fill soils of variable thickness (and in some places non-existent), underlain by thick layers of
residual granitic soils overlying un-weathered granite rock.
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5.1.1
Fill Soils
As anticipated the manmade platform (the bowls greens) which dominated the site consisted
of deep fill soils at its western extent where it had been built up. These soils were found to
from surface to depths of 3.0-4.6m. At positions on the eastern (cut section) of the platform
these soils were generally thin to non-existent. The fill soils consisted of pinholed, silty sand,
which appeared to be derived from residual granitic soils and occasionally residual sandstone
materials. The fill soils contained abundant granitic and sandstone cobbles and occasional
corestones.
The fill is anticipated to exhibit low expansion. This material was observed to have a loose to
medium dense consistency. Laboratory testing indicates the fill material classifies as SP
(poorly graded Sand) (USCS BS 1377, 1990). This material was generally found to have SPT
values in the order of 5-20, with a conservative average of approximately 10. Based on these
values the soil is anticipated to be cohesion-less and have an estimated angle of friction of
28-32.
5.1.2
Residual Granitic Soils
The residual granitic soils were generally found below the fill layer on the western border of
the site and from surface or below very thin topsoil layer on the eastern extent of the site.
These soils were found to depths of between 3.5-13.2m below egl. and consisted of gravelly
sands with locally high silt and clay horizons. Although core stone boulders were anticipated
in the horizon, none were intersected during drilling but are clearly distinguished on the ER
survey. The finer portion of the soil was made up of variably weathered, kaolinized
plagioclase (kaolin), whilst the coarser fraction predominantly of weathered quartz mineral
grains.
It must be noted that due to the high gravel content of these soils, SPT results are thought to
be an over estimation of actual conditions. SPT testing indicates variable SPT values for this
material, with the values generally increasing with depth. SPT values at depths of less than
5m where generally in the region of 10-20 indicating a medium dense consistency, a
conservative SPT value for this layer is 10. SPT values at depths greater than 5m where
generally in the region of 20-60 indicating a dense to very dense consistency, a conservative
SPT value for this layer is 25. These soils classify as SC to SM (clayey to silty Sand) and are
anticipated to exhibit varying cohesion with a conservative estimate of 10kPa an estimated
angle of friction of approximately 28-32 at depths of less than 5m and approximately 30-34
at depths in excess of 5.0m. This correlates well with the triaxial test result on the residual soil
at a depth of 5.5-5.9m (CBH4), tested to have an angle of friction of 30 and a cohesion of
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26.4kPa. The angle of friction and cohesion of the intact residual soil may be slightly higher
than that of disturbed residual material due to the relict granitic grain structure observed, but it
is difficult to quantify the degree to which this will increase the shear strength.
5.1.3
Granite Bedrock
The granite bedrock observed varied greatly in depths and was found from 3.5-13.2m below
egl. There was also almost no weathering zone between the overlying residual soils and
unweathered granite bedrock. The bedrock was porphyritic very coarse grained rock with
abundant accessory biotite. The rock mass, was slightly fractured to unfractured, the
orientations of the few joints observed varied between horizontal and 60-70º. Joint condition
varied, with closed joints to joint fill of 100mm, the wider joints were filled with gravel and
sands and appeared to have been heavily weathered by water seepage.
Uniaxial Compressive Strength (UCS) and point load testing indicates that slightly weathered
granite has a UCS of approximately 15-50MPa and the unweathered granite 50-120MPa.
These rocks are anticipated to have shear strength parameters far in excess of the overlying
soils. The stability of any rock face excavated for the development, must be assessed by a
geotechnical specialist once excavated to determine the orientation of the jointing of the rock
mass in relation to the cut. It is anticipated that the rock mass will provide a stable cut face if
exposed in the excavation.
5.2
Groundwater
Ground water strikes were recorded in all boreholes, and standpipe piezometers were
installed in every borehole. The level of the ground water was measured 24 hours after the
completion of drilling, and was found to vary between positions from 2.25-6.41m below egl.
Upon inspection of the existing retaining wall on the western side of the platform on site, large
quantities of seepage were observed (during the dry summer) from 2m below platform level,
as shown in Figure 5.1.
Upon enquiry about the seepage problem at the Glen Country Club house, they
acknowledged seepage came through the wall constantly to the point that a sump pump was
installed in the basement of the country club basement to pump the water elsewhere.
Pump testing of the boreholes on site indicates that the heavy ground water flow can be
anticipated into excavations on site, flow rates measured equate to a permeability of
approximately 0.1 to 0.001 cm/seconds for the residual granites. It also appears that heavier
seepage runs through the central portion of the site (around CBH3 and CBH4).
Limited tests have been undertaken and these have been done in the dry summer months, so
it is important to note that these tests have not quantified the extent of the problem, but rather
identified it. The seepage will need to be managed during construction and depending on
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chosen design, a suitable management option must be put in place to deal with this seepage
in the long term.
All excavations in soil below the depth of seepage must be battered back to a safe gradient or
the excavation sidewall must be stabilised to the satisfaction of the resident engineer.
Figure 5.1: Seepage observed through existing retaining wall.
5.3
Expansive, Dispersive and Collapsible Soils
The laboratory results received indicate that the soils are not expansive or dispersive.
Observation of the soils at the approximate founding depth of the development are intact and
therefore not considered to be collapsible, furthermore the pre-loading of these soils by the
overlying material should mitigate any collapse behaviour at this depth.
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6.
GEOTECHNICAL ANALYSIS 6.1
Bulk Earthworks
6.1.1
Excavation Conditions
According to SANS 1200D, soft excavation conditions are anticipated beneath the site, to
depths ranging from 3.5-13.2m, underlain immediately by hard rock excavation conditions.
Beneath the centre of the site where the deepest excavations (approximately 8.0m) are
anticipated, boreholes indicate soft conditions to in excess of 8.0m. It should be noted that the
depth of bedrock varied greatly over short distances and as such, hard rock excavation
should be anticipated within the cut, particularly towards the north and west of the site where
bedrock was shallower (3.5m at CBH1). Large core stone boulders were observed at surface
in the area surrounding the site, some small boulders were observed in the fill materials and
material interpreted as large corestones were identified in the ER survey. Some boulder class
A or B excavation conditions are anticipated.
Based on assessment of the site, and the depth of the proposed cut (maximum 8m) an
estimate of approximately 80% of the excavation conditions are anticipated to be soft, 10%
boulder class A or B and 10% hard excavation conditions. Due to the very hard,
unweathered, unfractured nature of the bedrock, blasting should be included in the Bill of
Quantities for approximately 10% of the excavations undertaken, blasting may also be
required for large corestones in the profile.
The excavation conditions are described in Table 6.1:
Table 6.1: Excavation class description as per SANS 1200D
Excavation Class
Description
Soft
Excavation in material that can be efficiently removed by a
back-acting excavator of flywheel power approximately 0.10
kW per millimetre of tined-bucket width, without the use of
pneumatic tools such as paving breakers
Intermediate
Excavation in material that requires a back-acting excavator of
flywheel power exceeding 0.10 kW per millimetre of tinedbucket width or the use of pneumatic tools before removal by
equipment equivalent to that specified for soft excavation.
Hard
Hard rock excavation shall be excavation in material (excluding
boulder excavation) that cannot be efficiently removed without
blasting or wedging and splitting.
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Table 6.1: Excavation class description as per SANS 1200D
Excavation Class
Description
Boulder (excavation
class A)
Excavation in material containing more than 40% by volume of
boulders of size in the range of 0.03 – 20m3, in a matrix of soft
or smaller boulders.
Boulder (excavation
class B)
Excavation in material containing 10-40% by volume of
boulders of size in the range of 0.03 - 20m3, in a matrix of soft
or smaller boulders.
6.1.2
Geotechnical Analysis Parameters
The large excavation and particularly the cut proposed on the eastern side of the
development provides an inherent slope stability risk, this risk must be mitigated by
excavating the slope at a shallow angle or more likely by using lateral support methods.
Based on the findings of the geotechnical investigation, the profile through which the cut will
be excavated will consist predominantly of residual granitic soils. Therefore the shear strength
parameters of this material are the critical geotechnical design parameters for this structure.
In areas where there is sufficient space to batter back the cut slopes, above the ground water
level, these slopes should not exceed a gradient of 1V:1H in short term and:1V:2H in the long
term. The slopes should not exceed a height of 8m and if in excess, a benched slope must be
constructed with individual bench heights of less than 2m.
Where space does not permit a shallow angle cut slope, lateral support techniques must be
employed. The design of the lateral support should be undertaken by a suitably qualified
Geotechnical Engineer according to the Code of Practice for Lateral Support and Surface
Excavations and taking into account the geotechnical conditions (particularly the heavy
seepage conditions reported). The shear strength design parameters provided in Table 6.2.
can be used as a guideline.
Table 6.2: Estimated shear strength parameters
Material
Estimated Effective Cohesion c'(kPa)
Estimated Effective Angle
of Friction Φ' (degrees)
Fill
0
30
Residual Granite at
depths <5.0m
10
30
Residual Granite at
depths <5.0m
10
32
Corestones are anticipated to be present within the profile. Based on observation of boulders
at surface in the surrounding area, it is anticipated these boulders may be in excess of 5m in
SMEC | SOUTH AFRICA | GEOTECHNICAL 14
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
diameter. Furthermore literature identifies the problematic conditions caused by granite
corestones in the Clifton area (Brink, 1979). Due to the highly generally erodible and
permeable residual granite soils, high water flow and resultant erosion may lead to slope
instability. It will be possible to remove smaller corestones, whilst larger corestones will have
to be incorporated into the lateral support design. If piles are to be used for the lateral support
it must be noted that piling techniques capable of penetrating large corestones may be
required.
6.2
Foundation Conditions
The foundation loads of the basement parking complex are anticipated to be substantial, as
such the founding conditions were assessed at the anticipated depth of the proposed
foundation. It is envisaged that the foundations will be placed at a depth of approximately 48m below egl. SPT values at these depths generally indicate dense to very dense residual
granitic soils, the Estimated Allowable Safe Bearing Pressures (EASBP’s) correlated from
SPT testing at these depths indicate bearing pressures in the order of 200-400kPa. An
exception is the relatively loose conditions tested at BH5 up to a depth of approximately 6m,
where SPT testing indicates EASBP’s of approximately 100kPa. It should also be noted that
corestones at or close to the founding depth may lead to variable founding conditions.
Thus although spread foundations could be feasible over parts of the site, very low bearing
capacities have been recorded elsewhere. Furthermore, the ground water seepage may be
very high making the casting and cleaning of foundation bases in soils problematic. Pile
foundations, end bearing on bedrock are thus recommended over parts of the site. It should
be noted that corestones underlying the site may cause difficulties in terms of piling and
should be noted when selecting the method/s of piling used. The foundation loads of the
structure were unknown at the time this report was compiled.
7.
CONCLUSIONS AND RECOMENDATIONS This interpretive report covers the findings and test results received for a geotechnical
investigation for the proposed Clifton Garage “Redevelopment Precinct”, consisting of a 3
level basement parking garage, associated retail developments and an approximately 8m
retaining structure. The objective of the investigation is to determine the viability of the
project, provide geotechnical design parameters and recommendations of the design of
lateral retaining structures and foundations for the development. Although the site has a
number of geotechnical constraints, particularly heavy ground seepage, which will result in
cost implications, the development is considered viable as long as the recommendations
given in this report are followed.
SMEC | SOUTH AFRICA | GEOTECHNICAL 15
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
The geotechnical investigation of the site indicates that the site is underlain by granite
bedrock of the Cape Peninsula Pluton making up part of the Cape Granite Suite. The site
profile consists of layers of loose to medium dense fill derived from residual granite, underlain
by deep residual granite, medium dense to very dense sands, grading suddenly into very
hard rock, unweathered, unfractured granite bedrock.
Geotechnical conditions affecting the proposed development are:

The depth to bedrock varies across the site, with shallower bedrock towards the
northern and western parts of the site.

Heavy ground water seepage is anticipated below depths of approximately 2.0m. The
hydrostatic pressures and flow must be considered in the geotechnical and structural
design and the construction contractor must make provision to manage the heavy
seepage.

The following excavation class quantities are anticipated for the earthworks on site to
a depth of 8m (the current assumed Surface Bed level):
Soft Excavation:
80%
Boulder Class A or B: 10 %
Hard Excavation:

10%
The majority of the envisaged cut will be within the residual granitic soils, with the
estimated design shear strength parameters provided in Table 6.2.

The anticipated founding medium, at depths of 4-8m below egl., are anticipated to
have EASBP’s in the order 200-400kPa based on SPT test results, with the exception
of the south west corner of the site were EASBP’s of approximately 100kPa are
anticipated. It is envisaged that foundations would comprise a combination of spread
foundations where bedrock is relatively shallow on rock and end bearing pile
foundations socketed onto rock.

Although not intersected in the boreholes, the ER survey of the site indicates large
granitic corestones underlie the site within the residual soil horizon. These corestones
may lead to slope instability and require specialised piling equipment if this is
undertaken on site.

The retaining structure and foundations of the proposed development must be
designed by a qualified and registered Geotechnical Engineer, in line with national
guidelines and best practice.
We trust that this report will be found to be complete and adequate for your consideration.
Should further elaboration be required for any portion of this project, we would be pleased to
provide assistance.
SMEC | SOUTH AFRICA | GEOTECHNICAL 16
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
8.
REFERENCES 
Brink, A.B.A. (1979), Engineering Geology of Southern Africa, Volume 2. Building
Publications, Pretoria.

Johnson, M.R., Anhausser, C.R., Thomas, R.J. (1996) The Geology of South Africa.
The Geological Society of South Africa and the Council for Geoscience.

SANS 633:2012 Soil profiling and rotary percussion borehole logging on dolomite land
in Southern Africa for engineering purposes.

Weinert, H. H., (1964), Basic igneous rocks in road construction, Research Report
218, CSIR, Pretoria.
9.
CLOSING We trust that this report will assist you in the design and construction of the proposed project.
SMEC South Africa appreciate the opportunity of providing our services on this project and
look forward to working with you on future projects.
Should you have any questions, please do not hesitate to contact us.
Respectfully submitted,
SMEC South Africa (Pty) Ltd
SMEC | SOUTH AFRICA | GEOTECHNICAL 17
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
APPENDIX A: SITE PLANS
SMEC | SOUTH AFRICA | GEOTECHNICAL APPENDIX A
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
APPENDIX B: TEST PIT PROFILES AND PHOTOGRAPHS
SMEC | SOUTH AFRICA | GEOTECHNICAL APPENDIX B
TRIAL PIT LOG
HOLE NO: CTP1
Depth
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE
PROJECT NO: JG0012
SITE: GLEN COUNTRY CLUB, CLIFTON
X COORD: E18,375378
Y COORD: S33,942963
ELEVATION:
PAGE 1 of 1
Dynamic Probe Light
Equivalent SPT-N
Description
0.00
0.0
10
20
30
40
Ground Surface
Loose, slightly silty SAND
Slightly moist, dark brown, speckled white, pinholed,
imported. Topsoil.
0.35
Soft sandy SILT with some clay
Moist, brown, mottled black and orange, intact.
Abundant micas. Fill derived from residual granite.
0.5
0.70
Medium dense, very silty SAND
Moist, white, mottled orange, black and grey, intact,
imported. Abundant micas. Fill derived from residual
granite.
1.0
1.30
Termination: time constraint
End of Log
1.5
2.0
2.5
3.0
NOTES 1: 1* MOD/CRB sample at 0.7-1.3m.
2: Slight seepage at 1.0m.
3: Old burried wall inside of pit.
4: No side wall collapse
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Test pit 1 profile.
Test pit 1 spoil.
TRIAL PIT LOG
HOLE NO: CTP2
Depth
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE
PROJECT NO: JG0012
SITE: GLEN COUNTRY CLUB, CLIFTON
X COORD: E18,375057
Y COORD: S33,943225
ELEVATION:
PAGE 1 of 1
Dynamic Probe Light
Equivalent SPT-N
Description
0.00
0.0
0.20
10
20
30
40
Ground Surface
Loose, slightly silty SAND
Slightly moist, dark brown, speckled white, pinholed,
imported. Topsoil.
Medium dense sandy BOULDERS with some silt
Red brown, blotched white, imported. Fill derived from
residual sandstone.
0.5
0.70
Medium dense, very silty SAND
Moist, beige, speckled white, intact, imported. Abundant
micas. Fill derived from residual granite. Abundant
granitic cobbles.
1.0
1.20
Termination: time constraint
End of Log
1.5
2.0
2.5
3.0
NOTES 1: 1* FI sample at 0.7-1.2m.
2: No seepage.
3: Broken pipe in test pit.
4: No side wall collapse.
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Test pit 2 profile.
Test pit 2 spoil.
TRIAL PIT LOG
HOLE NO: CTP3
Depth
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE
PROJECT NO: JG0012
SITE: GLEN COUNTRY CLUB, CLIFTON
X COORD: E18,375669
Y COORD: S33,943662
ELEVATION:
PAGE 1 of 1
Dynamic Probe Light
Equivalent SPT-N
Description
0.00
0.0
10
20
30
40
Ground Surface
Slightly silty SAND and occasional cobbles
Dry, dark brown, speckled white and orange, pinholed,
imported. Fill.
0.40
Medium dense, slightly clayey SAND with some
cobbles
Moist, grey brown to orange, mottled red, intact. Fill.
With some granitic cobbles.
0.5
1.00
1.0
Soft, slightly sandy SILT and occasional gravel
Moist, white, mottled red, intact. Fill derived from
residual granite.
1.40
Termination: seepage at 1.4m
1.5
End of Log
2.0
2.5
3.0
NOTES 1: 1* FI sample at 0.4-1.0m and 1.0-1.4m.
2: Seepage at 0.7m.
3: Broken pipe in test pit.
4: No sidewall collapse.
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CHECKED BY: E.ODENDAAL Prof Reg: 4400445/11
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Test pit 3 profile.
Test pit 3 spoil.
TRIAL PIT LOG
HOLE NO: CTP4
Depth
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE
PROJECT NO: JG0012
SITE: GLEN COUNTRY CLUB, CLIFTON
X COORD: E18,375213
Y COORD: S33,943823
ELEVATION:
PAGE 1 of 1
Dynamic Probe Light
Equivalent SPT-N
Description
0.00
0.0
0.30
0.50
0.5
0.80
10
20
30
40
Ground Surface
Medium dense, sandy GRAVEL with occasional
cobbles
Dry, beige, blotched white, intact, imported, crushed
granite rock fill. Abundant quartzite gravel to cobbles
and micas.
Medium dense, slightly silty SAND and occasional
gravel
Dry, beige, speckled white, intact, imported, fill. Fill
derived from residual granite and hillwash. Abudant
micas, sandstone gravel and boulders.
Loose, slightly silty SAND
Slighty moist, white, speckled yellow, intact, imported,
fill. Fill.
Medium dense to dense, slightly gravelly SAND with
some cobbles
Slighty moist, grey brown, speckled orange, black and
white, intact. Residual granite.
1.0
1.30
Termination: dense residual granite
End of Log
1.5
2.0
2.5
3.0
NOTES 1: 1* FI sample at 0.74-1.28m.
2: Minor seepage at base of pit, 1.3m..
3: No side wall collapse.
4:
SMEC South Africa
MACHINE: By hand
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Test pit 4 profile.
Test pit 4 spoil.
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
APPENDIX C: BOREHOLE LOGS AND PHOTOGRAPHS
SMEC | SOUTH AFRICA | GEOTECHNICAL APPENDIX C
BOREHOLE LOG
0
W
A
S
S
P
T
W
A
S
S
P
T
61
31
Depth
(m)
Legend
Sample
Water
No. of
fract.
SPT- N
value
RQD %
Core
size
% Mat.
recov.
% Core
recov.
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE GEOTECH
PROJECT NO: JG0012
CLIENT NO:
SITE: GLEN COUNTRY CLUB, CLIFTON
KILOMETRE:
0.0
H
1
100
90
97
100
100
Ground Surface
Clayey, gravelly SAND
Moist, light brown, blotched white, grey mottled
yellow. Residual granitic grain structure.
3
23
100
N/A
3.5
4
85
N/A
5
94
6.2
N/A
7
130
Description
2
H
6
70
X COORD: E18,375133
Y COORD: S33,942151
ELEVATION:
PAGE 1 of 1
38
4.5
94
HOLE NO: CBH1
100
100
N/A
N/A
8
9
9.9
10
Soft to medium hard rock GRANITE
White, mottled orange, black and grey, medium to
highly weathered, moderately fractured, coarse
grained, massive, Cape Peninsula Pluton, Cape
Granite Suite.
Fractures
1.Horizontal, rough, sandy gravel fill ~50mm.
Medium to hard rock GRANITE
White mottled grey, orange and black, medium to
slightly weathered, moderately fractured, coarse
grained, massive, Cape Peninsula Pluton, Cape
Granite Suite.
Fractures.
1. Horizontal, rough, sandy gravel fill, closed to
40mm.
Soft zone at 6.1-6.2m retrieved as gravel.
Hard rock GRANITE
White, mottled grey, orange and black,
unweathered, unfractured, coarse grained,
massive, Cape Peninsula Pluton, Cape Granite
Suite.
Fractures.
1. ~70deg, rough, no filling , closed.
End of Log
11
12
NOTES 1: Core sample at 5.8-6.1
2:
3:
4:
CONTRACTOR: FAIRBROTHER GEO ENG
MACHINE: HD 300 DTH Drill rig
INCLINATION: VERTICAL
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Borehole1, Box 1 of 2: 0-8.42m
Borehole 1, Box 2 of 2: 8.42-9.9m
BOREHOLE LOG
0
NXC
W
A
S
NXC
S
P
T
NXC
W
A
S
NWD4
S
P
T
52
S
P
T
13
NWD4 W
A
S
NWD4
P
T
21
P
T
43
S
P
T
61
NWD4 W
A
S
NWD4
S
P
T
NWD4 W
A
S
NWD4
P
T
REF
P
T
REF
Depth
(m)
Legend
Sample
Water
No. of
fract.
SPT- N
value
RQD %
Core
size
% Mat.
recov.
% Core
recov.
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE GEOTECH
PROJECT NO: JG0012
CLIENT NO:
SITE: GLEN COUNTRY CLUB, CLIFTON
KILOMETRE:
0.0
H
41
1
H
2
HOLE NO: CBH2
X COORD: E18,374955
Y COORD: S33,942577
ELEVATION:
PAGE 1 of 1
Description
Ground Surface
Silty SAND
Moist, dark brown, mottled red, voided, fill,
abundant quartz gravel and concrete cobbles.
Hard rock granite at 4.3-4.6m, interpreted as
granite boulder.
NWD4 58
NWD4
S
3
H
4
4.6
NWD4 105
NWD4
S
NWD4 86
NWD4
S
H
5
6
6.1
Gravelly, clayey SAND
Moist, light brown, blotched white, mottled orange
and black, relict granitic grain structure. Residual
granite.
7
REF
Gravelly, silty SAND
Moist, beige, mottled white, grey and orange,
intact. Residual granite, abundAnt quartz gravel,
some relict structure in places.
8
H
9
NWD4 49
NWD4
S
10
10.4
End of Log
11
12
13
14
15
NOTES 1: 1*FI sample at 5.0-6.0m
2: Water level at 5.8m
3:
4:
CONTRACTOR: FAIRBROTHER GEO ENG
MACHINE: HD 300 DTH Drill rig
INCLINATION: VERTICAL
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Borehole 2, Box 1 of 1: 0-10.075m
BOREHOLE LOG
0
W
A
S
S
P
T
23
P
T
5
P
T
Depth
(m)
Legend
Sample
Water
No. of
fract.
SPT- N
value
RQD %
Core
size
% Mat.
recov.
% Core
recov.
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE GEOTECH
PROJECT NO: JG0012
CLIENT NO:
SITE: GLEN COUNTRY CLUB, CLIFTON
KILOMETRE:
0.0
H
HOLE NO: CBH3
X COORD: E18,374955
Y COORD: S33,942947
ELEVATION:
PAGE 1 of 2
Description
Ground Surface
Silty SAND
Moist, beige to orange brown, mottled white, black,
voided, fill, zones of sandy silt. materials vary in
derivation. Beach sand to granitic sandy silt.
1
109
2
S
27
3
S
13
3.5
58
4
S
P
T
39
22
4.0
Clayey SILT
Slightly moist, grey, mottled red, stiff, intact. Fill.
Gravelly, silty SAND
Moist, grey, blocthed white, mottled orange, black,
relict granitic grain strUcture. Residual granite.
5
S
P
T
44
6
26
7
S
P
T
W
A
S
43
H
8
NOTES 1: Core samples at 9.4-9.8 and 11.0-11.3
2:
3:
4:
CONTRACTOR: FAIRBROTHER GEO ENG
MACHINE: LH75 Drill rig
INCLINATION: VERTICAL
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BOREHOLE LOG
100
0
N/A
115
100
100
N/A
Depth
(m)
100
Legend
T
Sample
P
Water
RQD %
S
No. of
fract.
SPT- N
value
Core
size
% Mat.
recov.
% Core
recov.
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE GEOTECH
PROJECT NO: JG0012
CLIENT NO:
SITE: GLEN COUNTRY CLUB, CLIFTON
KILOMETRE:
100
N/A
Hard rock GRANITE
Orange to pink, blotched white, unfractured, slightly
weathered, coarse grained.
10.3
Very hard rock GRANITE
White, mottled grey, orange and black,
unweathered, very slightly to slightly fractured,
coarse grained.
Fractures.
1. 60 deg, round, sandy gravel, 30mm.
10.6
11
67
90
78
11.0
11.8
N/A
Hard rock GRANITE
Orange to pink, blotched white, very slightly
fractured, slightly weathered, coarse grained.
Fractures
1. Horizontal, rough, sandy gravel fill, 10-100mm.
13
96
100
N/A
14
Hard rock GRANITE
White, mottled grey, orange, black, unweathered,
very slightly fractured, coarse grained, massive.
Fractures.
1. 60deg, round, sandy gravel fill, 30mm.
Sandy GRAVEL
Moist, orange brown, speckled white, black, voided.
Residual granite. Interpreted as broken granite
saprolite.
12
86
Description
9.2
10
6
X COORD: E18,374955
Y COORD: S33,942947
ELEVATION:
PAGE 2 of 2
8.8
REF
9
100
HOLE NO: CBH3
14.0
Very hard rock GRANITE
White, mottled grey, orange, black, unweathered,
very slightly fractured, coarse grained, massive.
Fractures.
1. Horizontal, round, sandy gravel fill, 0-50mm.
End of Log
15
16
17
NOTES 1: Core samples at 9.4-9.8 and 11.0-11.3
2:
3:
4:
CONTRACTOR: FAIRBROTHER GEO ENG
MACHINE: LH75 Drill rig
INCLINATION: VERTICAL
FILE REF:
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DRILLING DATE: 06/03/2015
SMEC South Africa
DATE LOGGED: 10/03/2015
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Borehole 3, Box 1 of 2: 0-9.8m
Borehole 3, Box 2 of 2: 9.80-14.0m
BOREHOLE LOG
0
W
A
S
S
P
T
Depth
(m)
Legend
Sample
Water
No. of
fract.
SPT- N
value
RQD %
Core
size
% Mat.
recov.
% Core
recov.
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE GEOTECH
PROJECT NO: JG0012
CLIENT NO:
SITE: GELN COUNTRY CLUB, CLIFTON
KILOMETRE:
0.0
H
HOLE NO: CBH4
X COORD: E18,375563
Y COORD: S33,943301
ELEVATION:
PAGE 1 of 2
Description
Ground Surface
Gravelly , sandy SAND
Moist, beige, speckled white, black and orange,
pinholed, clayey sandy silt. Hillwash of granitic
origin.
1
7
72
S
2
P
T
10
3
3.1
63
S
H
E
L
B
S
P
T
13
13
Clayey, gravelly SAND
Moist, beige to white, mottled orange, speckled
black, intact, relict granitic structure, gravelly silty
sand. Residual granite. Sandy silt zones at 5.36.5m.
Y
4
80
5
S
P
T
S
H
E
L
B
Y
6
49
6.7
S
P
T
REF
7
135
Gravelly, silty SAND
Moist, light orange to white, mottled red, speckled
black, intact, residual granitic granite structure,
sandy gravel. Residual granite, 8.5-9.5m zones of
sandy silt, believed to constitute granite saprolite
close to very soft rock, granitic rock.
8
NOTES 1: No samples.
2:
3:
4:
CONTRACTOR: FAIRBROTHER GEO ENG
MACHINE: LH 75 Drill rig
INCLINATION: VERTICAL
FILE REF:
Template: SMEC BHLP03
DRILLING DATE: 06/03/2015
SMEC South Africa
DATE LOGGED: 10/03/2015
Consulting Engineers
LOGGED BY: R.FREESE
CHECKED BY: E.ODENDAAL
South Africa
Prof Reg: 400051/14
Prof Reg: 400445/11
+27 (0)12 481 3800
www.smec.com
BOREHOLE LOG
Depth
(m)
Legend
Sample
Water
No. of
fract.
SPT- N
value
RQD %
Core
size
% Mat.
recov.
% Core
recov.
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE GEOTECH
PROJECT NO: JG0012
CLIENT NO:
SITE: GELN COUNTRY CLUB, CLIFTON
KILOMETRE:
HOLE NO: CBH4
X COORD: E18,375563
Y COORD: S33,943301
ELEVATION:
PAGE 2 of 2
Description
120
9
10
134
11
149
12
13
108
46
74
13.1
Soft rock, GRANITE
White, mottled black, grey, sligthly to unweathered,
very slightly to unfractured, granite rock, very hard
rock, coarse grained, massive, granite, Cape
Peninsula Pluton, Cape Granite Suite.
N/A
14
126
100
100
N/A
15
15.3
End of Log
16
NOTES 1: No samples.
2:
3:
4:
CONTRACTOR: FAIRBROTHER GEO ENG
MACHINE: LH 75 Drill rig
INCLINATION: VERTICAL
FILE REF:
Template: SMEC BHLP03
DRILLING DATE: 06/03/2015
SMEC South Africa
DATE LOGGED: 10/03/2015
Consulting Engineers
LOGGED BY: R.FREESE
CHECKED BY: E.ODENDAAL
South Africa
Prof Reg: 400051/14
Prof Reg: 400445/11
+27 (0)12 481 3800
www.smec.com
Borehole 4, Box 1 of 3: 0-6.50m
Borehole 4, Box 2 of 3: 6.5-12.5m
Borehole 4, Box 3 of 3: 12.5-15.27m
BOREHOLE LOG
0
Depth
(m)
Legend
Sample
Water
No. of
fract.
SPT- N
value
RQD %
Core
size
% Mat.
recov.
% Core
recov.
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE GEOTECH
PROJECT NO: JG0012
CLIENT NO:
SITE: GLEN COUNTRY CLUB, CLIFTON
KILOMETRE:
0.0
HOLE NO: CBH5
X COORD: E18,375299
Y COORD: S33,943880
ELEVATION:
PAGE 1 of 1
Description
Ground Surface
Silty SAND
Very moist, black to beige, voided. Fill.
NWD4 26
1
NWD4
S
P
T
10
2
NWD4 W
A
S
NWD4
S
P
T
S
H
E
L
H
3
3.0
12
B
Y
3.7
4
Gravelly, very clayey SAND
Very moist, light brown, blotched white, mottled
orange and black, relict granitic grain structure.
Residual granite.
NWD4 43
5
NWD4
S
P
T
S
H
E
L
11
6
B
Y
7
NWD4 75
NWD4
S
P
T
N/A
6.3
7.4
REF
100
100
N/A
9
NWD4 99
100
100
N/A
10
Gravelly, very silty SAND
Very moist, light brown, blotched white, mottled
orange, black, relict granitic grain structure.
Residual granite.
Silty SAND to GRAVEL
Very moist, light orange brown, mottled white and
black, relict granitic grain structure. Residual
granite, interpreted to be saprolite ripped by drill bit.
8
NWD4 110
Sandy SILT
Very moist, beige, mottled grey, intact. Residual
granite.
10.0
Very hard rock GRANITE
White, mottled black, unweathered, unfractured to
very slightly fractured, coarse grained, Cape
Peninsula Pluton Cape Granite Suite.
End of Log
11
12
NOTES 1: Standing water level at 2.25m
2: Core sample at 8.65-9.0m
3:
4:
CONTRACTOR: FAIRBROTHER GEO ENG
MACHINE: HC 6000 Drill rig
INCLINATION: VERTICAL
FILE REF:
Template: SMEC BHLP03
DRILLING DATE: 06/03/2015
SMEC South Africa
DATE LOGGED: 10/03/2015
Consulting Engineers
LOGGED BY: R.FREESE
CHECKED BY: E.ODENDAAL
South Africa
Prof Reg: 400051/14
Prof Reg: 4400445/11
+27 (0)12 481 3800
www.smec.com
Borehole 5, Box 1 of 2: 0-8.97m
Borehole 5, Box 2 of 2: 8.97-10.0m
BOREHOLE LOG
0
Depth
(m)
Legend
Sample
Water
No. of
fract.
SPT- N
value
RQD %
Core
size
% Mat.
recov.
% Core
recov.
CLIENT: CCTMPM
PROJECT: CLIFTON GARAGE GEOTECH
PROJECT NO: JG0012
CLIENT NO:
SITE: GELN COUNTRY CLUB, CLIFTON
KILOMETRE:
0.0
59
1
S
P
T
T
Ground Surface
Clayey, sandy SILT
Moist, beige, blotched red and grey, mottled yellow
and black, intact. Residual granite.
Clayey, silty SAND
Moist, light grey and light brown, blotched white,
mottled orange, black, relict granitic grain structure.
Residual granite.
3
10
30
S
Description
2.3
63
P
X COORD: E18,375701
Y COORD: S33,943741
ELEVATION:
PAGE 1 of 1
9
2
S
HOLE NO: CBH6
4
P
T
13
5
61
S
P
T
6
25
6.8
81
S
7
P
T
Clayey, silty SAND
Moist, light brown, blotched white, mottled orange
and black, intact, relict granitic granite structure.
Residual granite becoming sandier with depth.
30
8
110
S
P
9
T
27
T
55
93
S
P
10
10.4
End of Log
11
12
NOTES 1: 1* FI sample at 3.0-4.5
2: 1*FI sample at 7.0-7.95
3: Standard water level at 4.125m
4:
CONTRACTOR: FAIRBROTHER GEO ENG
MACHINE: HC 6000 Drill rig
INCLINATION: VERTICAL
FILE REF:
Template: SMEC BHLP03
DRILLING DATE: 06/03/2015
SMEC South Africa
DATE LOGGED: 10/03/2015
Consulting Engineers
LOGGED BY: R.FREESE
CHECKED BY: E.ODENDAAL
South Africa
Prof Reg: 400051/14
Prof Reg: 400445/11
+27 (0)12 481 3800
www.smec.com
Borehole 6, Box 1 of 2: 0-7.95m
Borehole 6, Box 2 of 2: 7.95-10.45m
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
APPENDIX D: DRILLERS LOGS
SMEC | SOUTH AFRICA | GEOTECHNICAL APPENDIX D
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
APPENDIX E: LABORATORY RESULTS
SMEC | SOUTH AFRICA | GEOTECHNICAL APPENDIX E
ROCKLAB REPORT
2015-SMEC-GEOTECHNICAL-01
CONFIDENTIAL
Issued by:
ROCKLAB
(ROCK MECHANICS & EXCAVATION LABORATORIES)
230 ALBERTUS STREET
LA MONTAGNE
PRETORIA
SOUTH AFRICA
TEL: +27 12 481 3894
FAX: +27 12 481 3812
E-MAIL: CHENJ@ROCKLAB.CO.ZA
RESULTS OF ROCK PROPERTIES TESTS
Sampling Site: Clifton Garage
BY
DR J. F. CHEN
Submitted to:
SMEC GEOTECHNICAL
16 MARCH 2015
2
CONTENTS
TABLE 1
RESULTS OF UNIAXIAL COMPRESSIVE STRENGTH TESTS
TABLE 2
RESULTS OF ROCK POINT LOAD STRENGTH TESTS
APPENDIX 1
FAILURE CODES OF ROCK COMPRESSION TESTS
TABLE 1
RESULTS OF UNIAXIAL COMPRESSIVE STRENGTH TESTS
Client: SMEC
Sampling Site: Clifton Garage
2015/3/16
SPECIMEN PARTICULARS
Rocklab
Specimen
No
Borehole
No
6121UCS-01
UCS-02
Note:
SPECIMEN DIMENSIONS
Depth
From.. To..
m
BH 3
BH 5
11.00 - 11.30
8.65 - 9.00
Rock
Diameter
Height
Type
mm
mm
51.73
51.69
134.8
132.3
All tests were conducted according to the ISRM's Specification.
Ratio
of Height
to
diameter
2.6
2.6
SPECIMEN TEST RESULTS
Mass
Density
Failure
Load
Strength
(UCS)
Failure
Note
Code
g
g/cm³
732.7
740.2
2.59
2.67
kN
62.5
249.2
MPa
29.7
118.7
XA
XA
1 - Sample was weathered.
1
TABLE 2
Client:
RESULTS OF POINT LOAD STRENGTH TESTS
SMEC SA
SPECIMEN
ROCKLAB Borehole
Specimen
No
No
6095-
PLT-01
PLT-02
PLT-03
PLT-04
Sampling Site: Clifton Garage
PARTICULARS
Sample
Rock
depth
From.. To..
Type
m
BH 3
BH 5
BH 3
BH 1
11.00 - 11.30
8.65 - 9.00
9.40 - 9.80
5.85 - 6.10
Core
Diameter
D
Height
(mm)
(mm)
51.85
51.85
51.85
51.85
51.85
51.85
51.65
51.65
51.65
51.65
51.65
51.65
51.77
51.77
51.77
51.77
51.77
51.77
51.77
51.77
51.77
51.77
52.03
52.03
52.03
52.03
52.03
52.03
52.03
52.03
52.03
52.03
Note: All tests were conducted according to the ISRM's suggested method.
1 - Diametrial loading,
2 - Axial Loading
Core
16-03-2015
SPECIMEN TEST RESULTS
Failue
Equivalent Point Load
Load
Core
Strength
IS
P
Diameter
(kN)
(mm)
(MPa)
Corrected
Test
Code
IS(50)
(MPa)
27.23
27.95
31.40
6.01
3.65
2.41
2.20
1.06
1.85
51.85
51.85
51.85
42.40
42.96
45.53
2.23
1.36
0.89
1.22
0.57
0.89
2.27
1.38
0.91
1.14
0.54
0.85
1
1
1
2
2
2
26.28
23.73
26.58
21.12
21.73
12.20
4.67
8.75
5.99
51.65
51.65
51.65
41.57
39.50
41.81
7.91
8.14
4.57
2.70
5.60
3.42
8.03
8.26
4.64
2.49
5.04
3.16
1
1
1
2
2
2
27.44
23.79
24.62
24.33
28.23
10.10
13.17
11.55
13.10
8.28
5.50
4.13
2.02
2.10
4.50
51.77
51.77
51.77
51.77
51.77
42.53
39.60
40.28
40.05
43.14
3.77
4.91
4.31
4.89
3.09
3.04
2.63
1.24
1.31
2.42
3.83
4.99
4.38
4.96
3.14
2.82
2.37
1.13
1.18
2.26
1
1
1
1
1
2
2
2
2
2
28.01
26.68
25.33
25.51
25.31
12.01
6.86
7.55
11.71
13.00
4.57
6.21
6.56
4.97
7.02
52.03
52.03
52.03
52.03
52.03
43.08
42.04
40.96
41.11
40.95
4.43
2.53
2.79
4.32
4.80
2.46
3.51
3.91
2.94
4.19
4.51
2.58
2.84
4.40
4.89
2.30
3.25
3.57
2.69
3.83
1
1
1
1
1
2
2
2
2
2
Note
APPENDIX 1
CLASSIFICATION OF ROCK SPECIMEN FAILURE MODE INFLUENCED /
NOT INFLUENCED BY DISCONTINUITIES DURING COMPRESSION
TESTING
FAILURE NOT INFLUENCED BY DISCONTINUITIES (INTACT)
DESCRIPTION OF SUB CODES
TYPE
CODE
A
B
X
SLIDING SHEAR FAILURE
COMPLETE CONE DEVELOPMENT
Y
SPLITTING
BREAKING INTO A LOT OF PIECES
FAILURE INFLUENCED BY DISCONTINUITIES
DESCRIPTION OF SUB CODES
TYPE
CODE
A
B
PARTIAL FAILURE ON DISCONTINUITY
FAILURE COMPLETELY ON DISCONTINUITY
◦
◦
1
AT 0-10 TO AXIS
AT 0-10 TO AXIS
2
AT 11-20 TO AXIS
◦
AT 11-20 TO AXIS
3
AT 21-30 TO AXIS
◦
AT 21-30 TO AXIS
4
AT 31-40◦ TO AXIS
AT 31-40◦ TO AXIS
5
AT 41-50 TO AXIS
◦
AT 41-50 TO AXIS
6
AT 51-70 TO AXIS
◦
AT 51-70 TO AXIS
7
AT 71-90 TO AXIS
◦
AT 71-90 TO AXIS
0
Multiple Discontinuities
Multiple Discontinuities
◦
◦
◦
◦
◦
Example: Failure Type3B: Failure completely on a discontinuity with an orientation of
◦
◦
between 21 and 30 to the specimen axis.
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
APPENDIX F: ELECTRICAL RESISTIVITY SURVEY RESULTS
SMEC | SOUTH AFRICA | GEOTECHNICAL APPENDIX F
ENGINEERING & EXPLORATION GEOPHYSICAL SERVICES CC
CK94/10526/23 Geophysical Contractors
170 Jakaranda Street,
Doringkloof,
Gauteng,0157
012 - 6673369 (tel.) 6675186(fax)
E-mail: eegs@iafrica.com
4th April, 2015
SMEC South Africa (Pty) Ltd,
P O Box 72927,
Lynwood Ridge 0040
Attn: Mr. Ryan Freese
Dear Sir,
GLEN COUNTRY CLUB RESISTIVITY SURVEY
1. Introduction
The methods and results are given here of a geophysical survey carried out in Clifton around
the bowling greens of the Glen Country Club. The object of the survey is map changes in
bedrock elevation.
Several boreholes have been drilled around the club, where an underground garage is
planned, but additional information is desired. As the condition of the greens is sensitive to
any activity other than bowling, resistivity was chosen as the least intrusive method with
which to acquire that information. The country rock is granite and a well-defined electrical
contrast between moist overburden and underlying rock was expected.
Fieldwork was performed on the 30th and 31st March. Traverses were carried out around the
perimeter of the greens and on walkways separating them to obtain six resistivity profiles.
2. Instrumentation, data collection methods and reduction procedure
2.1 Instrumentation
An ABEM LS resistivity meter was employed for the work. The ABEM system automates
data collection by accessing multiple electrodes through a multicore cable so that several
hundred readings reflecting both lateral and vertical changes in resistivity are collected in a
reasonable time. The data are stored in the resistivity meter.
2.2 Data collection
A Schlumberger-Wenner configuration was used on the two longest perimeter lines, which
are 120 metres in length, whilst a dipole-dipole configuration was used for the four 40 metre
long cross lines, the latter so that a slightly better exploration depth could be achieved,
though at the expense of a higher noise level. The electrode separation was one metre. As
the surveyed area is flat, no measurements of elevation differences along the traverses were
required.
2.3 Data reduction and presentation
Outliers were removed from the apparent resistivity data prior to modelling using Res2Dinv.
A common colour scale was chosen for all the models to allow better comparison of the
sections.
3. Results
The locations of the traverses are shown on figure 1 and the models are presented in figures 2
and 3.
The model for ER1 shows a resistive basement, except in the north where it descends below
the coverage of the model (figure 2). The basement surface is mostly horizontal, between six
to eight metres below ground level with steps separating different levels, but its course is
interrupted by two pinnacles. Above basement is a conductor with embedded blocks of
higher resistivity. Inland, on ER3, the well-defined basement is absent; instead there are
three resistive blocks projecting upward into an otherwise conductive layer (figure 2). As the
connecting lines are short, the exploration depth is reduced to about six metres, or about the
level of the shallowest depth to basement. Despite the lack of penetration a suggestion of
basement is visible on ER2 and ER5, and perhaps at the western end of ER6, but it is absent
on ER2 (figure 3). Otherwise, these models are characterised by a conductor encompassing
occasional resistive blocks, capped by a surfical resistor of varying thickness.
The conductor is expected to be moist sand, the resistive blocks in the conductor perhaps
boulders and the surficial resistor dry compact soil. Resistive basement is taken to be rock,
an interpretation that agrees with the depth to granite recorded in a draft log for BH3. Rock
head appears to get deeper towards the east, that is inland. The pinnacles may be a
conglomeration of boulders resting on basement.
Yours sincerely,
R.W.Day. Pr.Sci.Nat.
ER5
E R2
ER3
E R1
BH4
ER4
ER6
BH5
BH6
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
APPENDIX G: BOREHOLE PUMP TEST RESULTS
SMEC | SOUTH AFRICA | GEOTECHNICAL APPENDIX G
PUMP TEST ON BH4
TIME STARTED: 09H00
WATER LEVEL: 3.650 @08H30
FLOW METER READING:9068
TIME (min) DROP (m)
1
1
1
1,5
2
2,5
3
3,5
4
4,5
5
5,5
6
6,5
7
7,5
8
8,5
9
9,5
10
11
12
13
14
15
16
17
18
19
20
22
24
26
28
30
35
40
45
50
55
60
65
3,65
4,85
5,19
5,26
5,22
5,25
5,23
5,23
5,23
5,22
5,20
5,26
5,27
5,35
5,47
5,40
5,33
5,34
5,36
5,42
5,44
5,42
5,45
5,54
5,52
5,49
5,45
5,46
5,48
5,50
5,52
5,54
5,55
5,33
5,35
5,30
5,33
5,45
5,31
5,20
5,24
5,23
5,02
FLOW
VOLUME
(l) RECOVERY (m) FLOW DIFFERENTIAL(l)
Flow Rate l/sec
906,80
4.73
0,00
0,00000
907,2
4.73
0,40
#DIV/0!
908,9
4.46
1,70
#DIV/0!
909,3
4,35
0,40
0,01333
909,6
4,29
0,30
0,01000
910,2
4,25
0,60
0,02000
910,6
4,22
0,40
0,01333
911,1
4,22
0,50
0,01667
911,6
4,10
0,50
0,01667
912,0
4,18
0,40
0,01333
912,8
4,17
0,80
0,02667
913,2
4,17
0,40
0,01333
913,5
4,16
0,30
0,01000
914,1
4,16
0,60
0,02000
914,7
4,16
0,60
0,02000
915,2
4,15
0,50
0,01667
915,4
4,14
0,20
0,00667
915,7
4,14
0,30
0,01000
916,3
4,14
0,60
0,02000
916,8
4,14
0,50
0,01667
917,3
4,14
0,50
0,01667
918,2
4,13
0,90
0,01500
919,2
4,12
1,00
0,01667
920,2
4,11
1,00
0,01667
921,2
4,11
1,00
0,01667
922,2
4,10
1,00
0,01667
923,0
4,10
0,80
0,01333
923,8
4,10
0,80
0,01333
924,8
4,090
1,00
0,01667
925,8
4,085
1,00
0,01667
926,8
4,085
1,00
0,01667
927,7
4,075
0,90
0,00750
929,5
4,065
1,80
0,01500
931,0
4,060
1,50
0,01250
932,8
4,050
1,80
0,01500
934,3
4,040
1,50
0,01250
938,2
4,030
3,90
0,01300
943,4
4,020
5,20
0,01733
946,6
4,015
3,20
0,01067
950,0
4,015
3,40
0,01133
953,4
4,010
3,40
0,01133
956,2
4,005
2,80
0,00933
959,8
4,00
3,60
0,01200
Flow rate
m3/sec
0,00E+00
#DIV/0!
#DIV/0!
1,33E-05
1,00E-05
2,00E-05
1,33E-05
1,67E-05
1,67E-05
1,33E-05
2,67E-05
1,33E-05
1,00E-05
2,00E-05
2,00E-05
1,67E-05
6,67E-06
1,00E-05
2,00E-05
1,67E-05
1,67E-05
1,50E-05
1,67E-05
1,67E-05
1,67E-05
1,67E-05
1,33E-05
1,33E-05
1,67E-05
1,67E-05
1,67E-05
7,50E-06
1,50E-05
1,25E-05
1,50E-05
1,25E-05
1,30E-05
1,73E-05
1,07E-05
1,13E-05
1,13E-05
9,33E-06
1,20E-05
70
75
80
85
90
95
100
120
140
160
180
210
240
270
300
360
5,23
5,47
5,43
5,44
5,43
5,43
5,43
5,42
5,43
5,43
5,43
5,42
5,43
5,43
5,43
5,43
962,3
966,3
970,3
973,2
976,3
979,2
982,0
992,4
1008,8
1021,3
1033,7
1055,1
1075,3
1096,2
1117,6
1155,0
3,99
3,980
3,980
3,975
3,965
3,965
3,960
3,880
3,880
3,710
3,68
3,68
3,660
2,50
4,00
4,00
2,90
3,10
2,90
2,80
10,40
16,40
12,50
12,40
21,40
20,20
20,90
21,40
37,40
AVG
0,00833
0,01333
0,01333
0,00967
0,01033
0,00967
0,00933
0,00867
0,01367
0,01042
0,01033
0,01189
0,01122
0,01161
0,01189
0,01039
0,01357
8,33E-06
1,33E-05
1,33E-05
9,67E-06
1,03E-05
9,67E-06
9,33E-06
8,67E-06
1,37E-05
1,04E-05
1,03E-05
1,19E-05
1,12E-05
1,16E-05
1,19E-05
1,04E-05
1,36E-05 1,36E-05
PUMP TEST ON BH3
TIME STARTED: 08H00
WATER LEVEL: 4.555 @08H30
FLOW METER READING:1161.6 Litres
TIME(min) DROP(m)
1
4,56
1
6,43
1,5
8,40
2
8,55
2,5
8,64
3
8,66
3,5
8,68
4
8,70
4,5
8,72
5
8,73
5,5
8,74
6
8,75
6,5
8,75
7
8,76
7,5
8,77
8
8,78
8,5
8,78
9
8,78
9,5
8,78
10
8,79
110
8,79
12
8,80
13
8,80
14
8,81
15
8,81
16
8,81
17
8,82
18
8,82
19
8,83
20
8,83
22
8,84
24
8,85
26
8,85
28
8,85
30
8,86
35
8,88
40
8,89
45
8,90
50
8,91
55
8,92
60
8,92
65
8,93
FLOW
VOLUME
FLOW
(l) RECOVERY (m) DIFFERENTIAL(l)Flow Rate l/sec
1161,60
8,12
0
#VALUE!
1162,1
8,12
0,50
#DIV/0!
1163,7
6,23
1,60
0,05333
1164,3
6,14
0,60
0,02000
1165,0
6,01
0,70
0,02333
1165,7
5,92
0,70
0,02333
1166,4
5,83
0,70
0,02333
1167,1
5,77
0,70
0,02333
1167,9
5,75
0,80
0,02667
1168,4
5,71
0,50
0,01667
1169,2
5,70
0,80
0,02667
1169,9
5,68
0,70
0,02333
1170,5
5,66
0,60
0,02000
1171,2
5,65
0,70
0,02333
1171,9
5,64
0,70
0,02333
1172,5
5,63
0,60
0,02000
1173,2
5,61
0,70
0,02333
1173,9
5,60
0,70
0,02333
1174,6
5,59
0,70
0,02333
1175,2
5,59
0,60
0,02000
1176,5
5,58
1,30
0,00022
1177,3
5,56
0,80
-0,00014
1177,8
5,45
0,50
0,00833
1179,1
5,43
1,30
0,02167
1180,4
5,52
1,30
0,02167
1181,7
5,51
1,30
0,02167
1183,0
0,55
1,30
0,02167
1184,4
5,49
1,40
0,02333
1185,6
5,48
1,20
0,02000
1186,9
5,48
1,30
0,02167
1189,9
5,46
3,00
0,02500
1192,6
5,44
2,70
0,02250
1195,0
5,44
2,40
0,02000
1197,6
5,43
2,60
0,02167
1200,1
5,42
2,50
0,02083
1206,4
5,40
6,30
0,02100
1212,8
5,37
6,40
0,02133
1219,0
5,35
6,20
0,02067
1225,3
5,33
6,30
0,02100
1231,4
5,32
6,10
0,02033
1237,7
5,31
6,30
0,02100
1247,7
5,30
10,00
0,03333
Flow rate
m3/sec
#VALUE!
#DIV/0!
5,33E-05
2,00E-05
2,33E-05
2,33E-05
2,33E-05
2,33E-05
2,67E-05
1,67E-05
2,67E-05
2,33E-05
2,00E-05
2,33E-05
2,33E-05
2,00E-05
2,33E-05
2,33E-05
2,33E-05
2,00E-05
2,17E-07
-1,36E-07
8,33E-06
2,17E-05
2,17E-05
2,17E-05
2,17E-05
2,33E-05
2,00E-05
2,17E-05
2,50E-05
2,25E-05
2,00E-05
2,17E-05
2,08E-05
2,10E-05
2,13E-05
2,07E-05
2,10E-05
2,03E-05
2,10E-05
3,33E-05
70
75
80
85
90
95
100
120
140
160
180
210
240
270
300
360
420
8,94
8,95
8,96
8,96
8,96
8,97
8,98
8,98
9,00
9,15
9,02
8,67
9,05
9,05
9,05
9,05
9,05
1255,00
1256,1
1262,2
1268,2
1274,3
1280,5
1287,4
1309,0
1333,7
1356,3
1380,0
1414,0
1447,4
1478,5
1513,9
1580,1
1646,5
5,29
5,28
5,28
5,27
5,26
5,24
5,23
5,20
5,18
5,15
5,12
7,30
1,10
6,10
6,00
6,10
6,20
6,90
21,60
24,70
22,60
23,70
34,00
33,40
31,10
35,40
66,20
66,40
AVG
0,02433
0,00367
0,02033
0,02000
0,02033
0,02067
0,02300
0,01800
0,02058
0,01883
0,01975
0,01889
0,01856
0,01728
0,01967
0,01839
0,01844
0,02081
2,43E-05
3,67E-06
2,03E-05
2,00E-05
2,03E-05
2,07E-05
2,30E-05
1,80E-05
2,06E-05
1,88E-05
1,98E-05
1,89E-05
1,86E-05
1,73E-05
1,97E-05
1,84E-05
1,84E-05
2,08E-05
BH4 Pump Test Results
Log Time (Minutes)
1
10
100
1000
0,00
Drawdown (meters)
1,00
2,00
3,00
4,00
5,00
6,00
BH3 Pump Test Results
Log Time (Minutes)
1
0,00
Drawdown (meters)
1,00
2,00
3,00
4,00
5,00
6,00
7,00
8,00
9,00
10,00
10
100
1000
Clifton Garage Geotechnical Investigation
Interpretive Geotechnical Report
APPENDIX H: SITE CROSS-SECTIONS
SMEC | SOUTH AFRICA | GEOTECHNICAL APPENDIX H
LEGEND
GEOLOGICAL UNIT
FILL / HILLWASH
RESIDUAL GRANITE
GRANITIC ROCK
GROUND WATER LEVEL
CLIENT
No.
REVISIONS
DATE
DRG SIZE
SCALE
A3
NTS
DESIGNED
267 Kent Avenue, Randburg
P.O. Box 1462, Pinegowrie,
South Africa, 2123
Website: //www.smec.com
Tel. (011) 369-0600
Fax (011) 886-4589
DATE DRAWN
PROJECT
PROJECT NO
PHASE
DISCIPLINE
STAGE
CHECKED
Pequenino
DRAWING DISCRIPTION
DRAWN
CHECKED
DRAWING NUMBER
DOC TYPE
TYPE
LEVEL
NUMBER
L/O
REVISION
LEGEND
GEOLOGICAL UNIT
FILL / HILLWASH
RESIDUAL GRANITE
GRANITIC ROCK
GROUND WATER LEVEL
CLIENT
No.
REVISIONS
DATE
DRG SIZE
SCALE
A3
NTS
DESIGNED
267 Kent Avenue, Randburg
P.O. Box 1462, Pinegowrie,
South Africa, 2123
Website: //www.smec.com
Tel. (011) 369-0600
Fax (011) 886-4589
DATE DRAWN
PROJECT
PROJECT NO
PHASE
DISCIPLINE
STAGE
CHECKED
Pequenino
DRAWING DISCRIPTION
DRAWN
CHECKED
DRAWING NUMBER
DOC TYPE
TYPE
LEVEL
NUMBER
L/O
REVISION
LEGEND
GEOLOGICAL UNIT
FILL / HILLWASH
RESIDUAL GRANITE
GRANITIC ROCK
LOCATION OF CROSS SECTIONS
CLIENT
GROUND WATER LEVEL
No.
REVISIONS
DATE
DRG SIZE
SCALE
A3
NTS
DESIGNED
267 Kent Avenue, Randburg
P.O. Box 1462, Pinegowrie,
South Africa, 2123
Website: //www.smec.com
Tel. (011) 369-0600
Fax (011) 886-4589
DATE DRAWN
PROJECT
PROJECT NO
PHASE
DISCIPLINE
STAGE
CHECKED
Pequenino
DRAWING DISCRIPTION
DRAWN
CHECKED
DRAWING NUMBER
DOC TYPE
TYPE
LEVEL
NUMBER
L/O
REVISION