Original source · versioned page text
Geotechnical Report Dec 2013 Revision 1
Attached to the e-mail REC13/0146 - Response to Information Request - Email 2.
GEOTECHNICAL INVESTIGATION Proposed Subdivision, 55 Lake MacDonald Drive, Cooroy Report For Kalkev Pty Ltd c/- Callaghan & Toth Consulting Engineers Report No. 13008-001-Rev1 2 December 2013 Tectonic Geotechnical Pty Ltd PO Box 899 Buderim Qld 4556 Mobile: 0437 755 750 / 0437 756 711 www.tectonicgeo.com.au A.B.N. 83 165 727 828
See the original
The page text is free to read. Viewing or downloading an original file needs an account.
Log in to see the originalLog in to download the original file
Large file: the download may take up to a minute.
Searchable page text hides email addresses. Original files are unchanged and may show email addresses.
Full text of the other 44 pages
Page 2
55 LAKE MACDONALD DRIVE, COOROY
Document Review
Document No. Revision Prepared By Reviewed By Date Issued
001 0 Darryn Quinn Ashley Davey 5 November 2013
001 1 Darryn Quinn Ashley Davey 2 December 2013
Report Distribution
Revision Method of Delivery Issued To
0 Electronic Mr Lex Toth ([email protected])
1 Electronic Mr Lex Toth ([email protected])
Prepared By: Reviewed By:
Darryn Quinn RPEQ 7602 Ashley Davey RPEQ 8159
Principal Geotechnical Engineer Principal Geotechnical Engineer
2 December 2013
Report No. 137632019-001-R-Rev0 i
Page 3
55 LAKE MACDONALD DRIVE, COOROY Executive Summary This report details the results of a geotechnical investigation carried out for a proposed 31 lot residential subdivision at 55 Lake MacDonald Drive, Cooroy. The geotechnical investigation was undertaken by Tectonic Geotechnical Pty Ltd (Tectonic) for Kalkev Pty Ltd, at the request of Callaghan & Toth Consulting Engineers (C&T). The geotechnical investigation comprised excavation/drilling of test pits and boreholes, and subsequent laboratory testing. This report summarises the results of the investigation and provides recommendations regarding site preparation, earthworks, and pavement design parameters. The proposed development will comprise the subdivision of existing Lot 136 on MCH978 into 32 new residential allotments. Construction has commenced on the initial four lots fronting Lake MacDonald Drive. The next stage comprises three lots fronting Wilgee Court. This current investigation addresses site conditions on Stages 3 and 4 of the development. The site investigation comprised excavation of thirteen test pits across the site to depths of up to 2.2m below ground level (BGL). Representative soil samples were obtained from the test pits and forwarded to a geotechnical testing laboratory for soil classification analysis. An additional two hand auger boreholes and dynamic cone penetrometer (DCP) tests were undertaken in the western drainage gully. The subsurface conditions encountered in the test pits generally comprised about 0.2m of loose to medium dense silty sand topsoil over about 0.1m to 0.2m of loose to medium silty sand (similar material as the topsoil but no vegetation), then loose to medium dense clayey sand (clay fines of low to medium plasticity) over high plasticity, stiff, sandy/silty clay. The main exception to the above profile was test pit TP8, which was located within the drainage gully near the western boundary of the site. TP8 was positioned on the outer edge of the proposed pavement, and encountered wet, very loose silty sand and sand over stiff clay. The boreholes located in the drainage gully encountered very loose silty sand topsoil over soft saturated silty clay to about 0.5m BGL, then firm silty clay to about 0.8m BGL, then stiff (or stiffer) silty clay. Groundwater was encountered in two test pits during the investigation, being TP8 at 0.3m BGL and TP10 at 1.4m BGL. Topsoil stripping depths are expected to be in the order of 150mm to 200mm across the site. If earthworks are conducted during or following wet weather, the silty sand is expected to lose significant strength upon wetting up. Deeper stripping to remove the 100mm to 150mm thick silty sand layer below the topsoil may be required. Following topsoil stripping, we expect that the exposed subgrade will comprise the silty sand layer or underlying clayey sand. A preliminary CBRE of 10% may be adopted for the clayey sand. For sandy clay subgrades, a presumptive CBR of 5% may be adopted, provided appropriate drainage measures are included in the design. If silty clay subgrade is exposed, CBR values less than 3% may be possible, in which case, additional overexcavation and replacement may be required. At the location of test pit TP8, the wet, very loose silty sand and sand must be removed prior to filling. The exposed silty clay may also be wet and should be treated by oveexcavation and replacement, or be tyned and dried. Excavations to the depths of the test pits (generally 1.5m BGL, and TP10 at 2.2m BGL) are expected to be within the limits of medium to large excavators and dozers. 2 December 2013 Report No. 137632019-001-R-Rev0 ii
Page 4
55 LAKE MACDONALD DRIVE, COOROY
Table of Contents
INTRODUCTION........................................................................................................................................................ 1
PROPOSED DEVELOPMENT................................................................................................................................... 1
SITE DESCRIPTION.................................................................................................................................................. 1
METHOD OF INVESTIGATION................................................................................................................................. 6
4.1 Fieldwork ...................................................................................................................................................... 6
4.2 Laboratory Testing........................................................................................................................................ 6
INVESTIGATION FINDINGS ..................................................................................................................................... 7
5.1 Regional Geology ......................................................................................................................................... 7
5.2 Subsurface Conditions.................................................................................................................................. 7
5.3 Laboratory Test Results................................................................................................................................ 9
ENGINEERING ASSESSMENT .............................................................................................................................. 10
6.1 Earthworks.................................................................................................................................................. 10
6.1.1 Site Preparation and Traffickability........................................................................................................ 10
6.1.2 Excavations........................................................................................................................................... 11
6.1.3 Filling..................................................................................................................................................... 11
6.2 Pipelines ..................................................................................................................................................... 12
6.3 Pavement Design Parameters .................................................................................................................... 12
LIMITATIONS .......................................................................................................................................................... 13
TABLES
Table 1: Summary of Laboratory Results ............................................................................................................................ 9
TEXT FIGURES
Text Figure 1: Image showing ground surface contours (courtesy Sunshine Coast Council [SCC] My Maps).................... 2
Text Figure 2: Construction works on Lots 1 to 4 fronting Lake Macdonald Drive............................................................... 3
Text Figure 3: Stage 3, Area of Lots 16, 18, 19, 28, 29 (approx.) ....................................................................................... 3
Text Figure 4: Location of test pit TP8 ................................................................................................................................ 4
Text Figure 5: Stage 4 – Lots 13 to 15 (approx.)................................................................................................................. 4
Text Figure 6: DCP hammer/rod at HA1 ............................................................................................................................. 5
Text Figure 7: DCP hammer/rod at HA2 ............................................................................................................................. 5
Text Figure 8: Test pit TP2.................................................................................................................................................. 7
Text Figure 9: Test pit TP8.................................................................................................................................................. 8
Text Figure 10: Spoil from test pit TP12.............................................................................................................................. 8
2 December 2013
Report No. 137632019-001-R-Rev0 iii
Page 5
55 LAKE MACDONALD DRIVE, COOROY FIGURES Figure 1: Site Plan APPENDICES APPENDIX A Proposed Subdivision Layout (Callaghan & Toth Drawing No. 1225-30) APPENDIX B Test Pit & Borehole Reports and Explanatory Notes APPENDIX C Laboratory Test Certificates APPENDIX D Report Limitations 2 December 2013 Report No. 137632019-001-R-Rev0 iv
Page 6
55 LAKE MACDONALD DRIVE, COOROY
INTRODUCTION
This report details the results of a geotechnical investigation carried out for a proposed 31 lot residential
subdivision at 55 Lake MacDonald Drive, Cooroy. The geotechnical investigation was undertaken by Tectonic
Geotechnical Pty Ltd (Tectonic) for Kalkev Pty Ltd, at the request of Callaghan & Toth Consulting Engineers
(C&T).
The geotechnical investigation comprised excavation of test pits, drilling of boreholes and subsequent
laboratory testing. This report summarises the results of the investigation, and provides recommendations
regarding:
Preliminary stripping depths for road and allotment fills (based on test pits and general site observations);
Preliminary pavement design parameters (i.e. CBR values based on laboratory testing, field testing, and
presumptive values based on subgrade types);
Traffickability of excavator working in the gully (to clear vegetation and for placement of rock spalls and
geotextile); and
Sewer and stormwater pipe laying conditions (i.e. excavatability; foundation suitability).
PROPOSED DEVELOPMENT
The proposed development will comprise the subdivision of existing Lot 136 on MCH978 into 32 new
residential allotments, as shown on C&T Drawing No. 1225-30 (attached in Appendix A). The subdivision
comprises four Stages. Stage 1 consists of four lots (Lots 1 to 4) currently under construction, and Stage 2
consists of three lots (Lots 5 to 7) fronting Wilgee Court. This site investigation encompasses two stages,
designated as Stage 3 (located over the western half of the site) and Stage 4 (located over the eastern half of
the site). Stage 3 comprises16 new lots (proposed Lots 16 to 31), and Stage 4 comprises nine lots (proposed
Lots 8 to 16). The two Stages are separated by proposed park land over an existing drainage gully line.
Access to the Stage 3 allotments will be from a new road off Blue Wren Place. Access to Stage 4 will be via a
new road, Masonry Street, entering the subdivision from the north. Proposed Lots 5 to 7 will be accessed by
new driveways off Wilgee Court. Those driveways cross an existing table drain adjacent Wilgee Court.
The sewer line and manholes have been installed in Stage 4 in the eastern side of the stage (i.e. near the
central drainage gully).
It is proposed to raise the ground levels for the new lots about 500mm above the Q100 Inundation line, which is
shown on the C&T drawing in Appendix A. That results in required filling of about 600mm across proposed
Lots 16, 18, 19, and 28 to 31 in Stage 3, and Lots 13 to 15 in Stage 4. Filling in the order of about 1m height
may be required for the new access road into Stage 3.
We also understand that the proposed works may include rehabilitation of the existing drainage gullies, which
may also serve as stormwater detention basins. Those works comprise regrading of the invert of the existing
drainage gully, placement of an approximate 300mm thick layer of rock spalls, jute matting, topsoil and mulch.
The exact scope of rehabilitation works had not been finalised at the time of this investigation.
SITE DESCRIPTION
The proposed development site is a 60ha parcel of land described as Lot 136 on MCH978 (No. 55 Lake
MacDonald Drive, Cooroy). The site has limited road frontage along Lake MacDonald Drive along the
southern boundary, and Wilgee Court on the eastern boundary. The remainder of the site is bounded by
existing residential subdivisions or rural lots along the northern, eastern and western sides.
Stage 4 comprises gently sloping ground (less than 5º) to the south-west towards the drainage gully that
traverses the site in a south to north direction. Stage 3 consists of a gently sloping northerly trending ridge
(about 5º to 7º), with gullies located on the eastern and western sides.
2 December 2013
Report N0. 13008-001-Rev1 1
Page 7
55 LAKE MACDONALD DRIVE, COOROY
The site is mostly well grassed, with some isolated stands of trees around the site. The drainage gully is more
densely vegetated with long grasses and trees along the banks.
The drainage gully commences as a roadside table drain adjacent Wilgee Court along the eastern side of the
site, heading south, and then running adjacent to Lake MacDonald Drive, before heading in a northly direction
through the centre of the site.
Existing water and sewer lines also run through the middle of the site in a similar alignment to the drainage
gully.
Drainage gullies
Water & sewer
easement
Blue Wren Place
Text Figure 1: Image showing ground surface contours (courtesy Sunshine Coast Council [SCC] My Maps)
General site conditions are shown on Figure 1 (presented at the end of this report), and Text Figures 2 to 7
below.
2 December 2013
Report N0. 13008-001-Rev1 2
Page 8
55 LAKE MACDONALD DRIVE, COOROY
Text Figure 2 Construction works on Lots 1 to 4 fronting Lake Macdonald Drive
Lots 28/29
Lots 18/19
Lot 16
Text Figure 3: Stage 3, Area of Lots 16, 18, 19, 28, 29 (approx.)
2 December 2013
Report N0. 13008-001-Rev1 3
Page 9
55 LAKE MACDONALD DRIVE, COOROY
Approximate location of TP8
Text Figure 4: Location of test pit TP8
Lot 13
Lots 14/15
Text Figure 5: Stage 4 – Lots 13 to 15 (approx.)
2 December 2013
Report N0. 13008-001-Rev1 4
Page 10
55 LAKE MACDONALD DRIVE, COOROY Text Figure 6: DCP hammer/rod at HA1 Text Figure 7: DCP hammer/rod at HA2 2 December 2013 Report N0. 13008-001-Rev1 5
Page 11
55 LAKE MACDONALD DRIVE, COOROY
METHOD OF INVESTIGATION
4.1 Fieldwork
The subsurface investigation comprised excavation of thirteen test pits (designated TP1 to TP13) to depths of
up to 2.2 m below ground level (BGL) across the site using either a Komatsu PC220 (22 tonne) excavator or a
Komatsu PC78MR (8 tonne) excavator. The smaller excavator was used for the test pits on the eastern side
of the site (Stage 3) due to access difficulties in getting the larger excavator across the drainage gully.
Test pits TP1 to TP6 were located within proposed residential allotments. Test pits TP7 to TP9, TP12 and
TP13 were located in proposed road areas. Test pit TP10 was located in where a sewer manhole is
proposed, and test pit TP11 was excavated to assess the material near the central drainage gully for
accessibility. No deeper test pits were excavated in Stage 3, as the sewer line had been installed.
Test pits TP1 to TP4, TP7, TP8, TP12 and TP13 were located within Stage 4, with test pits TP5, TP6, TP9 to
TP11 being located in Stage 3.
Pocket penetrometer (PP) testing was carried out on the sidewalls of the test pits to gain an indication of soil
strength/consistency. Disturbed samples were taken from the test pits for laboratory soil classification testing.
In addition to the above, two hand augered boreholes (HA1 and HA2) were drilled within the western drainage
gully to depths of 1.0m BGL. Dynamic cone penetrometer (DCP) tests were carried out adjacent to the
boreholes, and also at the location of TP8 to assess the strength/consistency of the soil types within the gully
area. The hand augers were located near the widest part of the drainage gully, where it was expected that the
greatest accumulation of sediments may occur.
Test pit and borehole locations were positioned on site using offsets from the road centreline and boundary
survey pegs. Test co-ordinates were obtained using a hand held GPS with an accuracy of ±5m, and are
provided on the test pit and borehole logs.
The fieldwork was carried out in the presence of an experienced geotechnical engineer from Tectonic on 17
October 2013 (test pits) and 28 November 2013 (hand augered boreholes). Reports of test pits and boreholes
(with DCP test results), along with explanatory notes are presented in Appendix B. Test pit and borehole
locations are shown in Figure 1, and also on C&T layout drawing in Appendix A.
4.2 Laboratory Testing
Selected soil samples were dispatched to Geotech (SC) Pty Ltd, a NATA accredited geotechnical testing
laboratory located in Kawana, for geotechnical testing. Laboratory testing was undertaken in accordance with
Australian Standard AS1289 Method for Testing Soils for Engineering Purposes and comprised:
Atterberg Limits (liquid limit, plastic limit, plasticity index, linear shrinkage) and Fines Content analyses
for soil classification purposes; and
Soaked CBR (single point) for pavement design purposes.
A summary of the laboratory testing results is presented in Section 5.3, and the laboratory test certificates are
attached in Appendix C.
2 December 2013
Report N0. 13008-001-Rev1 6
Page 12
55 LAKE MACDONALD DRIVE, COOROY
INVESTIGATION FINDINGS
5.1 Regional Geology
The 1:100,000 Gympie Special Geological Map (Sheet 9445 and Part 9545) indicates that the site is underlain
by the Early to Middle Triassic-aged Kin Kin Beds formation comprising arenite, argillite, phyllite.
5.2 Subsurface Conditions
The subsurface conditions encountered in the test pits located in the proposed residential areas (TP1 to TP6)
generally comprised about 0.2m of loose to medium dense silty sand topsoil over about 0.1m to 0.2m of loose
to medium silty sand (similar material as the topsoil but no vegetation), then loose to medium dense clayey
sand. High plasticity, sandy/silty clay was encountered below the clayey sand in all test pits except TP3. Test
pit TP1 did not encountered the clayey sand layer (silty sand directly overlies clay).
Topsoil
Silty Sand
Clayey Sand
Sandy Clay
Text Figure 8: Test pit TP2
The test pits located in the proposed pavement areas (TP7, TP9, TP12 and TP13) encountered similar profiles
as TP1 to TP6. Test pit TP8, which was located at the edge of the drainage gully, encountered 0.3m of very
loose, grey/dark grey, moist silty sand with a high organic content over wet, very loose sand, then stiff sandy
clay at 0.5m depth. Some large logs were encountered in test pit TP12, and some smaller logs were found in
TP13.
2 December 2013
Report N0. 13008-001-Rev1 7
Page 13
55 LAKE MACDONALD DRIVE, COOROY
Wet, very loose sand
Silty clay
Text Figure 9: Test pit TP8
Logs within topsoil layer
Text Figure 10: Spoil from test pit TP12
Hand auger boreholes HA1 and HA2 encountered wet, very loose silty sand topsoil to about 0.1m to 0.2m
depth BGL over wet, soft silty clay, becoming firm at about 0.5m BGL, and stiff (or stiffer) at about 0.8m BGL.
At test pit TP8, stiff clay (PP=100kPa) was encountered at about 0.5m BGL, which is where the DCP test
indicated 1 to 2 blows per 100mm penetration. Similar results were noted for the DCP tests at HA1 and HA2,
2 December 2013
Report N0. 13008-001-Rev1 8
Page 14
55 LAKE MACDONALD DRIVE, COOROY where DCP blows >1 per 100mm were also recorded at depths of about 0.5m BGL. Therefore, at HA1 and HA2, the silty clay may actually be stiff from 0.5m BGL (DCP testing in wet silty clay can give low values that underestimate the strength of the material). Groundwater seepage was only encountered in test pits TP8 at a depth of 0.3m BGL and at TP10 at a depth of 1.4m BGL during the investigation. Groundwater was present in boreholes HA1 and HA2 at about 0.2m BGL. It should be noted that groundwater seepage may occur from more permeable horizons within the soil following periods of prolonged or heavy rainfall. Refer to detailed test pit reports and explanatory notes attached in Appendix B. 5.3 Laboratory Test Results The results of the laboratory testing are presented below in Table 1. Table 1: Summary of Laboratory Results Test Pit No. TP1 TP2 TP7 TP9 Depth (m) 0.2-0.3 0.3-0.5 0.3-0.7 0.3-0.5 Percent fines (%) 46 46 Liquid Limit (%) 23 29 Plastic Limit (%) 17 16 Plasticity index (%) 6 13 Linear Shrinkage (%) 4.5 10.0 CBR (%) 17.0 19.0 Field Moisture Content (%) 9.5 18.1 Optimum Moisture Content (%) 12.7 16.5 Fines Content is the % of clay/silt fraction in the soil profile The above laboratory test results indicate that the soil tested from TP1 is silty sand, with low liquid limit silt. . The sample tested from TP2 is clayey sand, with low plasticity clay. 2 December 2013 Report N0. 13008-001-Rev1 9
Page 15
55 LAKE MACDONALD DRIVE, COOROY
ENGINEERING ASSESSMENT
6.1 Earthworks
Advice provided to Tectonic by the client indicates that earthworks will comprise the placement of up to
approximately 0.6m of fill across the lower lying areas of the site to raise the ground levels about 0.5m above
the Q100 inundation level.
Filling in excess of 0.6m is expected in the area of the proposed new road into Stage 3, where the ground
level drops about 0.5m towards the drainage gully (e.g. location of test pit TP8).
Excavations to depths of up to about 2.5m are expected for the sewer line on Stage 4.
Excavations in the drainage gully areas as stripping and clearing is proposed, together with placement of rock
spalls, topsoil and muclh.
Additional earthworks may occur at future residential areas to prepare level ground for slab-on-ground
construction.
6.1.1 Site Preparation and Traffickability
The general soil profile comprised about 0.2m of grey silty sand topsoil over about 0.2m of loose to medium
dense grey silty sand (similar material to the topsoil, but lacking roots). Underlying the silty sand is loose to
medium dense clayey sand, then high plasticity sandy/silty clay. At test pit TP1, TP8 and TP11, the clayey
sand layer was not encountered.
Stripping depths to remove the surface vegetation layer are expected to be typically about 0.2m deep. Deeper
stripping is expected in the area of the draining gullies. Two test pits excavated in or close to the drainage
gullies (TP8 and TP11) indicated yup to about 0.4m to 0.5m of stripping may be required in those areas.
The subgrade materials exposed after site stripping are expected to comprise predominantly grey, loose to
medium dense silty sand. Whilst in a dry condition (as experienced at the time of the investigation), the silty
sand forms a suitable subgrade for pavement construction and/or further filling. However, this material will be
subject to significant strength loss from repetitive vehicle loading (particularly from rubber tyred plant) or if they
become wet. If earthworks are undertaken during or following wet periods the grey silty sand may need to be
overexcavated and replaced with a suitable fill material.
If the silty sands are to be overexcavated, the exposed material is expected to comprise loose to medium
dense clayey sand. Laboratory tests indicated CBR values of 17% and 19% for that material, with field
moisture contents either just below the optimum moisture content (OMC) at test pit TP7, or at OMC at test pit
TP9. Some moisture conditioning (addition of water or drying) is to be expected prior to placement of
pavement materials.
In future residential areas, the potential subgrade materials are expected to be of suitable strength to allow for
adequate compaction of future fill to be carried out (provided silty sands are not wet).
At test pit TP8, the soil profile comprised very loose, high organic silty sand over wet, very loose sand, then
high plasticity silty clay. The very loose silty sand and sand are not considered suitable for subgrade platforms
and will be required to be excavated. Following removal of the silty sand and sand, it is expected that the
exposed silty clay will be wet, and will require conditioning (tyned, dried and recompacted) prior to placement
of fill.
At test pit TP12, and to a lesser extent at TP13, large logs were found in the topsoil layer, to a depth of about
0.4m BGL. This material must be fully removed prior to placement of fill.
Due to the potential for poor traffickability across the site during and after wet periods, placement of a
minimum 150 mm thick granular working platform may be required, particularly along haul roads and any
laydown areas.
After stripping of topsoil, the natural subgrade should be ‘proof rolled’ using a minimum 10 tonne drum roller in
order to identify any ‘soft spots’. Treatment of any ‘soft spots’ may involve excavation and replacement with
2 December 2013
Report N0. 13008-001-Rev1 10
Page 16
55 LAKE MACDONALD DRIVE, COOROY select fill or tyning, appropriate moisture adjustment and compaction. Proof rolling should be carried out in the presence of an experienced geotechnical engineer. The site should be graded to shed surface water runoff away from earthworks and/or construction areas. . Appropriate erosion and sediment control measures must be installed prior to commencement of earthworks at this site. In addition to the above assessments, a “proof” roll was conducted using the 8 tonne excavator across the gully area between Stages 3 and 4, near the existing concrete culvert. This area was assessed for traffickability as it appeared to be wet and soft ground. The excavator was able to traverse this area with no difficulties. It is expected that this area would become softer and more difficult to access following wet weather. Although the surface conditions were dry and hard at the time of the investigation, tyre ruts about 200mm deep were noted in the area between the gully and test pit TP5 on the eastern side of the drainage gully. 6.1.2 Excavations Excavations for future services are expected to be in loose to medium dense clayey sand and stiff (or stiffer) sandy/silty clays. Test pit TP10 was located in an area of a future sewer manhole, with an invert level approximately 2.5m BGL. The subsurface profile comprised medium dense silty/clayey sand over stiff sandy clay to 2.2m BGL (maximum depth reach of excavator). Some groundwater seepage was noted at a depth of 1.4m BGL. Excavations in the silty/clayey sand and sandy clay materials are expected to be achievable using typical earthmoving plant (e.g. medium to large excavators, dozers). Rock was not encountered in any of the other test pits, which were excavated to depths of up to 1.5m BGL. Unsurcharged excavation batters could be temporarily formed no steeper than 1V:2H in the natural soils. The presence of groundwater seepage may necessitate flatter batters. The above recommendations do not supersede any existing safety regulations or legislation applicable to excavations (e.g. limits on personnel entry into trenches). Groundwater seepage was noted to be slow, and is expected to be removable by grading excavations to a low point and pumping water from a sump. 6.1.3 Drainage Gullies We understand that the drainage gullies may be rehabilitated by stripping and re-grading the existing ground surface, followed by placement of rock spalls, and erosion protection measures (jute matting, topsoil, and mulch). Following striping of surface vegetation, the exposed material is expected to comprise silty clay. Where this material was noted to be wet (e.g. test pit TP8, boreholes HA1 and HA2), a significant reduction is strength was observed (e.g. soft to firm). At test pit TP11 (located within the central gully), the silty clay underlying the topsoil was noted to be moist and stiff. The 7 tonne excavator was also able to traverse the area adjacent to the central drainage gully. At boreholes HA1 and HA2, the silty clay was described as firm at about 0.5m BGL, then stiff (or stiffer) below 0.8m BGL (based on DCP test results). As discussed in Section 5.2, at HA1 and HA2, the silty clay may actually be stiff from 0.5m BGL. Based on the above results, it appears that stiff (or stiffer) clays are present at depths within 0.8m BGL. It is expected that stiff (or stiffer) silty clay will form a suitable foundation for the placement of rock spalls. If time and subsurface conditions permit, it is possible that the upper soft to firm clay recorded in HA1 and HA2 to a depth of 0.8m BGL, could be dried, tyned and re-compacted. This will reduce the volume of material to be stripped to provide a suitable foundation for placement of rock spalls. To achieve this, the drain will need to be cleaned out and re-graded to maintain flow towards the outlets, to allow for the clay to dry out so that tyning and compaction may be undertaken. 2 December 2013 Report N0. 13008-001-Rev1 11
Page 17
55 LAKE MACDONALD DRIVE, COOROY The presence of deeper deposits of alluvial materials within the drainage gullies should not be discounted. However, our assessment of the site topography and the subsurface conditions in the test pits and boreholes indicates that there is a low risk of deep alluvial deposits accumulating within the gullies. 6.1.4 Filling The proposed earthworks include filling of about 0.6m depth across the proposed Lots 16, 18, 19, and 28 to 31 in Stage 3, and Lots 13 to 15 in Stage 4. Future fill located within residential areas, pavement areas, or within the gully, should be compacted at moisture contents within the range of ±2% of optimum moisture content for Standard Compaction. Confirmatory compaction testing must be carried out at regular intervals. A minimum of two tests per vertical lift is recommended where structural fill heights are to exceed 300 mm. Further details for control and testing of fill are given in Australian Standard AS 3798-2007 Guidelines on Earthworks for Commercial and Residential Developments. Fill should be placed in 250 mm thick (loose thickness) layers and be compacted by repeated rolling to achieve a dry density ratio of at least 95% of the maximum Dry Density Ratio (DDR) for residential areas and gully fill, and 98% DDR for pavement fill (all Standard Compaction method). Fill must be ‘benched’ into the natural slope, over-filled by 0.5 m (horizontally) and then trimmed back to the well compacted material. 6.2 Pipelines The invert level for the sewer and water pipelines are typically expected to be about 1m to 2m BGL. The anticipated materials at that depth are expected to comprise mostly stiff (or stiffer) high plasticity sandy and silty clay, and medium dense clayey sand. The bases for the manholes are expected to be about 2.5m depth BGL. The founding strata for the pipeline and manholes is expected to have an allowable bearing capacity of at least 100kPa. As noted in Section 6.1.2, some groundwater seepage was encountered in the test pit at TP10 in Stage 3 thorough sandy layers within the sandy clay stratum. Seepage should be readily removable from pipeline excavations by pumping from a sump. 6.3 Pavement Design Parameters Pavement design will be dependent upon the subgrade materials present after earthworks. Following anticipated topsoil stripping (and where no filling is proposed), the exposed subgrade will comprise about 100mm of loose to medium dense silty sand over/or clayey sand. Laboratory testing indicated CBR values of 17% and 19% for the clayey sand (with low plasticity clay fines). Presumptive CBR values for clayey sand are 5% to 10% (Table 11 of Austroads Guide to Pavement Technology, Vers 2.1- 2013). Therefore, we recommend adoption of a design CBR of 10% for the clayey sand. The silty/sandy clay subgrade is expected to have a CBR value less than 5%, and possibly less than 3% for silty clay, in which case, additional subgrade treatment may be required, such as over-excavation and replacement with granular fill (e.g. roadbase) The above values are applicable to properly drained subgrades only, and should be confirmed by testing following earthworks. Properly drained subgrades’ require open graded drains, site grades that shed water and prevent ponding, and subsurface drains adjacent to pavements. Subgrade inspection and CBR testing should be carried out following bulk earthworks to confirm design CBR values. If subgrade materials are allowed to ‘dry out’, significant softening (and resulting subgrade strengths less than those nominated above) could occur on ‘wetting up’. 2 December 2013 Report N0. 13008-001-Rev1 12
Page 18
55 LAKE MACDONALD DRIVE, COOROY
LIMITATIONS
Your attention is drawn to the document “Report Limitations”, which is included in Appendix D of this report.
The statements presented in this document are intended to advise you of what your realistic expectations of
this report should be, and to present you with recommendations on how to minimise the risks associated with
the services provided for this project.
2 December 2013
Report N0. 13008-001-Rev1 13
Page 19
Tectonic Geotechnical Pty Ltd
PO Box 899
Buderim Qld 4556
M: 0437 755 700 / 0437 756 711
PROJECT:
55 LAKE MACDONALD DRIVE,
COOROY
TP5
TITLE:
TP9 SITE PLAN
TP4
TP6 CLIENT:
TP3 KALKEV PTY LTD
TP11
TP8 TP10
TP7 DRAWN: DATE:
HA1 TP13 DJQ 1/12/2013
TP1
TP12 CHECKED: DATE:
HA2 TP2 ACD 2/12/2013
SCALE:
0m 50m As Shown
LEGEND:
Test Pit Location
Hand Auger Location
PROJECT NO.: FIGURE: REV:
13008 1 1
Page 20
55 LAKE MACDONALD DRIVE, COOROY APPENDIX A Proposed Subdivision Layout (Callaghan & Toth Drawing No. 1225-30) 1 December 2013 Report No. 13008-001-Rev1
Page 21
55 LAKE MACDONALD DRIVE, COOROY APPENDIX B Test Pit and Hand Auger Reports and Explanatory Notes 1 December 2013 Report No. 13008-001-Rev1
Page 22
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP01
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 100.8 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491344 NORTHING 7079125
EQUIPMENT 22t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry, medium dense
SM Silty SAND, fine to medium grained, grey, low liquid limit silt, dry to moist, DS
medium dense LL=23
100.5
PL=17
Fines=46%
LS=4.5
CH Sandy CLAY, high plasticity, pale grey, orange, fine to medium grained sand,
moist, stiff PP=200kPa to
0.5 300kPa on
sidewall
Not Encountered
100.0
1.0
99.5
1.5
Test Pit TP01 terminated at 1.5m
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
99.0
2.0
98.5
2.5
98.0
3.0
Page 23
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP02
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 101.2 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491335 NORTHING 7079095
EQUIPMENT 22t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry to moist, medium dense
101.0 SC Clayey SAND, fine to medium grained, grey, orange, low plasticity clay, moist,
loose to medium dense
DS
LL=29
PL=16
Fines=46%
0.5 LS=10.0
Not Encountered
100.5
CH Sandy CLAY, high plasticity, pale grey, orange, fine to medium grained sand,
moist, stiff PP=100kPa to
200kPa on
sidewalls
1.0
100.0
1.5
Test Pit TP02 terminated at 1.5m
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
99.5
2.0
99.0
2.5
98.5
3.0
Page 24
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP03
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 100.8 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491363 NORTHING 7079180
EQUIPMENT 22t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry, medium dense
SM Silty SAND, fine to medium grained, grey, low liquid limit silt, dry, medium
dense
100.5
SC Clayey SAND, fine to medium grained, grey, orange, low plasticity clay, moist,
loose
0.5
Not Encountered
100.0
SC Clayey SAND, fine to medium grained, orange, red brown, medium to high
plasticity clay, moist, medium dense
1.0
DS
99.5
1.5
Test Pit TP03 terminated at 1.5m
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
99.0
2.0
98.5
2.5
98.0
3.0
Page 25
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP04
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 100.5 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491370 NORTHING 7079217
EQUIPMENT 22t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry, loose to medium dense
SM Silty SAND, fine to medium grained, grey, low liquid limit silt, dry, loose to
medium dense
SC Clayey SAND, fine to medium grained, grey, orange, low to medium plasticity
clay, moist, loose to medium dense
100.0 0.5
Not Encountered
CH Sandy CLAY, high plasticity, pale grey, orange/red brown, fine to medium
grained sand, moist, stiff
99.5 1.0
99.0 1.5
Test Pit TP04 terminated at 1.5m
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
98.5 2.0
98.0 2.5
97.5 3.0
Page 26
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP05
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 101.5 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491464 NORTHING 7079253
EQUIPMENT 8t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry, medium dense
SC Gravelly Clayey SAND, fine to medium grained, orange, medium plasticity clay,
fine to coarse size gravel (quatzose), dry, medium dense
101.0 0.5
Not Encountered
DS
100.5 1.0
CH Sandy CLAY, high plasticity, pale grey, orange/red brown, fine to medium slightly friable and fissured
grained sand, moist, stiff
DS
100.0 1.5
Test Pit TP05 terminated at 1.5m
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
99.5 2.0
99.0 2.5
98.5 3.0
Page 27
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP06
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 101.5 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491540 NORTHING 7079183
EQUIPMENT 8t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry, looses to medium dense
SM Silty SAND, fine to medium grained, grey, low liquid limit silt, dry, loose to
medium dense
SC Clayey SAND, fine to medium grained, grey, orange, low to medium plasticity
clay, dry to moist, medium dense
101.0 0.5
Not Encountered
DS
CH Sandy CLAY, high plasticity, orange/red brown, grey, fine to medium grained
sand, moist, very stiff PP=200kPa to
100.5 1.0 400kPa on
sidewall
100.0 1.5
Test Pit TP06 terminated at 1.5m
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
99.5 2.0
99.0 2.5
98.5 3.0
Page 28
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP07
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 101.3 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491375 NORTHING 7079146
EQUIPMENT 22t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry, medium dense
SM Silty SAND), fine to medium grained, grey, low liquid limit silt, dry, loose to
medium dense
101.0
SC Clayey SAND, fine to medium grained, grey, orange, low plasticity clay, dry to
moist, medium dense
Not Encountered
0.5 Bulk DS
CBR=17.0%
SC Clayey SAND, fine to medium grained, orange, brown, medium plasticity clay,
moist, medium dense
100.5
1.0
Test Pit TP07 terminated at 1.2m
100.0
1.5
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
99.5
2.0
99.0
2.5
98.5
3.0
Page 29
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP08
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 99.7 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491321 NORTHING 7079142
EQUIPMENT 22t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey/dark grey, low liquid limit
Groundwater seepage from 0.3m
silt, roots, moist, medium dense
99.5
SP SAND, fine to coarse grained, pale grey/grey, trace low plasticity fines, wet,
very loose
0.5
CH Sandy CLAY, high plasticity, pale grey, yellow, fine to medium grained sand,
moist, stiff
PP=100kPa on
sidewalls
99.0
Test Pit TP08 terminated at 0.7m
1.0
98.5
1.5
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
98.0
2.0
97.5
2.5
97.0
3.0
Page 30
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP09
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 102 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491483 NORTHING 7079235
EQUIPMENT 8t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry, loose
SM Silty SAND), fine to medium grained, grey, low liquid limit silt, dry, medium
dense
SC Clayey SAND, fine to medium grained, orange, red brown, low to medium
plasticity clay, dry to moist, medium dense
Bulk DS
CBR=19.0%
101.5 0.5
Not Encountered
101.0 1.0
Test Pit TP09 terminated at 1.3m
100.5 1.5
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
100.0 2.0
99.5 2.5
99.0 3.0
Page 31
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP10
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 101 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491533 NORTHING 7079169
EQUIPMENT 8t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry, loose to medium dense
SC Silty Clayey SAND, fine to medium grained, grey, brown, low plasticity fines,
trace fine to coarse size gravel, dry, medium dense
SC Clayey SAND, fine to medium grained, grey, yellow brown, medium plasticity
fines, trace fine to coarse size gravel, moist, medium dense
100.5 0.5
CI Sandy CLAY, medium plasticity, grey, yellow and red brown, fine to medium
grained sand, moist, stiff
Groundwater seepage from 1.4m
100.0 1.0
CI becoming pale grey, red brown
99.5 1.5
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
99.0 2.0
Depth reach limit of excavator
Test Pit TP10 terminated at 2.2m
98.5 2.5
98.0 3.0
Page 32
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP11
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 100.5 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491475 NORTHING 7079163
EQUIPMENT 8t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
wet, very loose
Not Encountered
CI Sandy CLAY, medium plasticity, grey, brown, fine to medium grained sand,
trace fine size gravel, moist, stiff
100.0 0.5
Test Pit TP11 terminated at 0.5m
99.5 1.0
99.0 1.5
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
98.5 2.0
98.0 2.5
97.5 3.0
Page 33
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP12
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 100.5 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491321 NORTHING 7079102
EQUIPMENT 22t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
logs, moist, medium dense
SC Clayey SAND, fine to medium grained, orange, grey, low plasticity clay, dry to
moist, loose to medium dense
Not Encountered
100.0 0.5
CH Silty CLAY, high plasticity, pale grey, orange, some fine to medium grained
sand, moist, stiff
99.5 1.0
Test Pit TP12 terminated at 1m
99.0 1.5
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
98.5 2.0
98.0 2.5
97.5 3.0
Page 34
Tectonic Geotechnical Pty Ltd TEST PIT NUMBER TP13
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 17/10/13 COMPLETED 17/10/13 R.L. SURFACE 100.5 DATUM m AHD
EXCAVATION CONTRACTOR Roberts Bros EASTING 491323 NORTHING 7079132
EQUIPMENT 22t excavator TEST PIT LOCATION Refer site plan
TEST PIT SIZE 600mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
E
SM Silty SAND (TOPSOIL), fine to medium grained, grey, low liquid limit silt, roots,
dry to moist, some small logs, medium dense
Not Encountered
SC Clayey SAND, fine to medium grained, orange, grey, low plasticity clay, moist,
loose to medium dense
100.0 0.5
CI Sandy CLAY, medium plasticity, pale grey, orange, fine to medium grained
sand, moist, stiff
99.5 1.0
Test Pit TP13 terminated at 1.1m
99.0 1.5
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 7/11/13
98.5 2.0
98.0 2.5
97.5 3.0
Page 35
Tectonic Geotechnical Pty Ltd BOREHOLE NUMBER HA1
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 28/11/13 COMPLETED 28/11/13 R.L. SURFACE 100.0 DATUM m AHD
DRILLING CONTRACTOR Tectonic EASTING 491304 NORTHING 7079122
EQUIPMENT Hand auger HOLE LOCATION Refer site plan
HOLE SIZE 100mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
HA
SM Silty SAND (TOPSOIL), fine to medium grained, dark grey, low liquid limit silt, 0
Groundwater seepage from 0.2m
roots, wet, very loose
CH Silty CLAY, high plasticity, pale grey, yellow, trace fine to medium grained sand, 0
wet, soft
0
0
0
99.5 0.5
becoming firm 1
2
DCP test indicates stiff at 0.8m 1
Borehole HA1 terminated at 0.7m
2
4
99.0 1.0
>10
98.5 1.5
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 1/12/13
98.0 2.0
97.5 2.5
97.0 3.0
Page 36
Tectonic Geotechnical Pty Ltd BOREHOLE NUMBER HA2
40 Glenn Vista Drive PAGE 1 OF 1
Chevallum Qld 4555
Telephone: 0437756711
CLIENT Kalkev Pty Ltd PROJECT NAME Residential Subdivision
PROJECT NUMBER 13008 PROJECT LOCATION 55 Lake MacDonald Drive, Cooroy
DATE STARTED 28/11/13 COMPLETED 28/11/13 R.L. SURFACE 100.0 DATUM m AHD
DRILLING CONTRACTOR Tectonic EASTING 491285 NORTHING 7079086
EQUIPMENT Hand auger HOLE LOCATION Refer site plan
HOLE SIZE 100mm LOGGED BY DJQ CHECKED BY ACD
NOTES RL estimated from site plan contours; co-ordinates taken from hand held GPS
Classification
Graphic Log
Samples
DCP Test (Blows/100 mm) /
Material Description Tests
Method
Symbol
Additional Observations
Water
Remarks
RL Depth
(m) (m)
HA
SM Silty SAND (TOPSOIL), fine to medium grained, dark grey, low liquid limit silt, 0
Groundwater seepage from 0.2m
roots, wet, very loose
0
CH Silty CLAY, high plasticity, pale grey, yellow, trace fine to medium grained sand, 0
wet, very soft
0
0
99.5 0.5
0
becoming firm to stiff 2
DCP indicates becoming stiff at 0.8m 1
Borehole HA2 terminated at 0.7m
1
1
99.0 1.0
2
2
4
6
7
98.5 1.5
BOREHOLE / TEST PIT 13008 LAKE MACDONALD DVE.GPJ GINT STD AUSTRALIA.GDT 1/12/13
98.0 2.0
97.5 2.5
97.0 3.0
Page 37
TERMS USED ON LOGS
DRILLING/EXCAVATION METHOD
AD* Auger Drilling RD Rotary Blade or Drag bit NQ Diamond Core - 47 mm
*V V-Bit RT Rotary Tri-cone bit NMLC Diamond Core - 52 mm
*T TC-Bit RA Rotary Air HQ Diamond Core - 63 mm
HA Hand Auger HMLC Diamond Core – 63mm
ADH Hollow Auger BH Tractor Mounted Backhoe
HA Hand Auger EX Tracked Hydraulic Excavator
WATER
GROUNDWATER NOT The observation of groundwater, whether present or not, was not possible due to drilling water,
OBSERVED surface seepage or cave in of the borehole/test pit.
GROUNDWATER NOT The borehole/test pit was dry soon after excavation. However, groundwater could be present in
ENCOUNTERED less permeable strata. Inflow may have been observed had the borehole/test pit been left open
for a longer period.
SAMPLING AND TESTING
SPT Standard Penetration Test to AS1289.6.3.1-2004
5,4,10 N=14 5,4,10 = Blows per 150mm. N = Blows per 300mm penetration following 150mm seating
30/65mm Where practical refusal occurs, the blows and penetration for that interval are reported
RW Penetration occurred under the rod weight only
HW Penetration occurred under the hammer and rod weight only
HB Hammer double bouncing on anvil
DS Disturbed sample
BDS Bulk disturbed sample
FV Field vane shear test expressed as uncorrected shear strength (sv = peak value, sr = residual value)
PP Pocket penetrometer test expressed as instrument reading in kPa
U50 Thin walled tube sample - number indicates nominal sample diameter in millimetres
DCP Dynamic cone penetration test
CPT Electronic cone penetration test
CPTu Electronic cone penetration test with pore pressure (u) measurement
Rev0
October 2013
Page 38
METHOD OF SOIL DESCRIPTION
USED ON LOGS
CLASSIFICATION AND INFERRED STRATIGRAPHY
Soil and rock is classified and described in borehole and test pit logs using the preferred method given in AS1726 – 1993,
(Amdt1 – 1994 and Amdt2 – 1994), Appendix A.The material properties are assessed in the field by visual/tactile methods.
Particle Size Plasticity Properties
Major Division Sub Division Particle Size40
BOULDERS > 200 mm
COBBLES 63 to 200 mm
Coarse 20 to 63 mm
GRAVEL Medium 6.0 to 20 mm
Fine 2.0 to 6.0 mm
Coarse 0.6 to 2.0 mm
C
SAND Medium 0.2 to 0.6 mm
Fine 0.075 to 0.2 mm
SILT 0.002 to 0.075
CLAY < 0.002 mm mm
MOISTURE CONDITION AS1726 - 1993
Symbol Term Description
D Dry Sands and gravels are free flowing. Clays & Silts may be brittle or friable and powdery.
M Moist Soils are darker than in the dry condition & may feel cool. Sands and gravels tend to cohere.
W Wet Soils exude free water. Sands and gravels tend to cohere.
CONSISTENCY AND DENSITY AS1726 - 1993
Symbol Term Undrained Shear Symbol Term Density Index % SPT “N” #
Strength
VS Very Soft 0 to 12 kPa VL Very Loose Less than 15 0 to 4
S Soft 12 to 25 kPa L Loose 15 to 35 4 to 10
F Firm 25 to 50 kPa MD Medium Dense 35 to 65 10 to 30
St Stiff 50 to 100 kPa D Dense 65 to 85 30 to 50
VSt Very Stiff 100 to 200 kPa VD Very Dense Above 85 Above 50
H Hard Above 200 kPa
In the absence of test results, consistency and density may be assessed from correlations with the observed behaviour of
the material.
# SPT correlations are not stated in AS1726 – 1993, and may be subject to corrections for overburden pressure and
equipment type.
Rev0
October 2013
Page 39
55 LAKE MACDONALD DRIVE, COOROY APPENDIX C Laboratory Test Results 1 December 2013 Report No. 13008-001-Rev1
Page 40
Quality of Materials Report
Client: Tectonic Geotechnical Pty Ltd Report Number: G13056 - 5/1
Client Address: PO Box 899 Buderim QLD 4556
Job Number: G13056 Report Date: 25/10/2013
Project: Laboratory Testing Project No:13008 Order Number: -
Location 55 Lake MacDonald Drive , Cooroy Page 1 of 1
Lab No: 97844 Sample Location
Date Sampled: 17/10/2013 Test Pit 1
Date Tested: 23/10/2013 Depth 0.2 - 0.3m
Sampled By: Client Supplied 21/10/13
Sample Method: N/A
Material Source: Site Spec Description: -
For Use As: - Lot Number: -
Remarks: - Spec Number: -
A.S. Sieve Sizes Specification Percent Specification
Minimum Passing Maximum
Test Method: AS1289.3.6.1
75.00 mm
53.00 mm
37.50 mm
26.50 mm
19.00 mm
13.2 mm
9.50 mm
6.7 mm
4.75 mm
2.36 mm
1.18 mm
0.600 mm
0.425 mm
0.300 mm
0.150 mm
0.075 mm 46
Atterberg Tests Test Method Specification Result Specification
Minimum Maximum
Liquid Limit (%) AS1289.3.1.2 23
Plastic Limit (%) AS1289.3.2.1 17
Plasticity Index AS1289.3.3.1 6
Linear Shrinkage (%) AS1289.3.4.1 4.5
Approved Signatory Form Number
This document is issued in accordance with NATA's
accreditation requirements. Accredited for compliance
with ISO/IEC 17025. REP AQUAL-1-7
Mel Burnett
NATA Accred No:1551
Page 41
Quality of Materials Report
Client: Tectonic Geotechnical Pty Ltd Report Number: G13056 - 6/1
Client Address: PO Box 899 Buderim QLD 4556
Job Number: G13056 Report Date: 25/10/2013
Project: Laboratory Testing Project No:13008 Order Number: -
Location 55 Lake MacDonald Drive , Cooroy Page 1 of 1
Lab No: 97845 Sample Location
Date Sampled: 17/10/2013 Test Pit 2
Date Tested: 23/10/2013 Depth 0.3 - 0.5m
Sampled By: Client Supplied 21/10/13
Sample Method: N/A
Material Source: Site Spec Description: -
For Use As: - Lot Number: -
Remarks: - Spec Number: -
A.S. Sieve Sizes Specification Percent Specification
Minimum Passing Maximum
Test Method: AS1289.3.6.1
75.00 mm
53.00 mm
37.50 mm
26.50 mm
19.00 mm
13.2 mm
9.50 mm
6.7 mm
4.75 mm
2.36 mm
1.18 mm
0.600 mm
0.425 mm
0.300 mm
0.150 mm
0.075 mm 46
Atterberg Tests Test Method Specification Result Specification
Minimum Maximum
Liquid Limit (%) AS1289.3.1.2 29
Plastic Limit (%) AS1289.3.2.1 16
Plasticity Index AS1289.3.3.1 13
Linear Shrinkage (%) AS1289.3.4.1 10.0
Approved Signatory Form Number
This document is issued in accordance with NATA's
accreditation requirements. Accredited for compliance
with ISO/IEC 17025. REP AQUAL-1-7
Mel Burnett
NATA Accred No:1551
Page 42
California Bearing Ratio Report (1 Point)
Client: Tectonic Geotechnical Pty Ltd Report Number: G13056 - 7/1
Client address: PO Box 899 Buderim QLD 4556
Job Number: G13056 Report Date: 28/10/2013
Project: Laboratory Testing Project No:13008 Order Number:
Location 55 Lake MacDonald Drive , Cooroy Page 1 of 1
Lab No: 97846 Sample Location
Date Sampled: 17/10/2013 Test Pit 7
Date Tested: 28/10/2013 Depth 0.3 - 0.7m
Sampled By: Client Supplied 21/10/13
Sample Method: N/A
Material Source: Site Test Method : AS1289.6.1.1
For Use As: - Lot Number: -
Remarks: - Item Number : -
Maximum Dry Density - MDD (t/m³) : 1.902 Dry Density after Soak (t/m³) : 1.888
Optimum Moisture Content - OMC (%) : 12.7 Moisture Content after Soak (%) : 11.9
Compactive Effort : Standard Density Ratio after Soak (%) : 99
Nominated % Maximum Dry Density
Compaction : 100 Field Moisture Content (%) : 9.5
Nominated % Optimum Moisture Content Moisture Content (Top) after Penetration
Compaction : 100 (%) : -
Moisture Content (Total) after Penetration
Achieved Dry Density before Soak (t/m³) : 1.906 (%) : -
Achieved Percentage of Maximum Dry Density
(%) : 100 CBR 2.5mm (%) : 17
Achieved Moisture Content (%) : 12.5 CBR 5.0mm (%) : 16
Achieved Percentage of Optimum Moisture
Content (%) : 98 Minimum Specified CBR Value (%) : -
Test Condition (Soaked/Unsoaked) / Soaking
Period (Days) : Soaked / 4 days
CBR Value (%) : 17.0
Swell (%) / Surcharge (kg): 1.0 / 4.5 kg
Soil Description : Silty Clayey Sand(SC)-fine to medium grained,yellow brown,low plasticity fines
Approved Signatory Form Number
This document is issued in accordance with NATA's accreditation
requirements. Accredited for compliance with ISO/IEC 17025. REP ACBR_1_3-3
Mel Burnett
NATA Accred No:1551
Page 43
California Bearing Ratio Report (1 Point)
Client: Tectonic Geotechnical Pty Ltd Report Number: G13056 - 8/1
Client address: PO Box 899 Buderim QLD 4556
Job Number: G13056 Report Date: 28/10/2013
Project: Laboratory Testing Project No:13008 Order Number:
Location 55 Lake MacDonald Drive , Cooroy Page 1 of 1
Lab No: 97847 Sample Location
Date Sampled: 17/10/2013 Test Pit 9
Date Tested: 28/10/2013 Depth 0.3 - 0.5m
Sampled By: Client Supplied 21/10/13
Sample Method: N/A
Material Source: Site Test Method : AS1289.6.1.1
For Use As: - Lot Number: -
Remarks: - Item Number : -
Maximum Dry Density - MDD (t/m³) : 1.753 Dry Density after Soak (t/m³) : 1.753
Optimum Moisture Content - OMC (%) : 16.5 Moisture Content after Soak (%) : 18.1
Compactive Effort : Standard Density Ratio after Soak (%) : 100
Nominated % Maximum Dry Density
Compaction : 100 Field Moisture Content (%) : 16.1
Nominated % Optimum Moisture Content Moisture Content (Top) after Penetration
Compaction : 100 (%) : -
Moisture Content (Total) after Penetration
Achieved Dry Density before Soak (t/m³) : 1.754 (%) : -
Achieved Percentage of Maximum Dry Density
(%) : 100 CBR 2.5mm (%) : 19
Achieved Moisture Content (%) : 16.4 CBR 5.0mm (%) : 19
Achieved Percentage of Optimum Moisture
Content (%) : 99 Minimum Specified CBR Value (%) : -
Test Condition (Soaked/Unsoaked) / Soaking
Period (Days) : Soaked / 4 days
CBR Value (%) : 19.0
Swell (%) / Surcharge (kg): 0.1 / 4.5 kg
Soil Description : Clayey Sand(SC)-fine to medium grained,brown,low to medium plasticity fines
Approved Signatory Form Number
This document is issued in accordance with NATA's accreditation
requirements. Accredited for compliance with ISO/IEC 17025. REP ACBR_1_3-3
Mel Burnett
NATA Accred No:1551
Page 44
55 LAKE MACDONALD DRIVE, COOROY APPENDIX D Report Limitations 1 December 2013 Report No. 13008-001-Rev1
Page 45
REPORT LIMITATIONS This report has been prepared for the purpose outlined in Tectonic’s proposal and no responsibility is accepted for the use of this report, in whole or in part, for any other purpose. The scope of Tectonic’s Services are as described in Tectonic’s proposal, and are subject to restrictions and limitations. Tectonic did not perform a complete assessment of all possible conditions or circumstances that may exist at the site referenced in the report. If a service is not expressly indicated, do not assume it has been provided. If a matter is not addressed, do not assume that any determination has been made by Tectonic in regards to it. Conditions may exist which were undetectable given that economic and time constraints limit the practical extent of geotechnical investigation. Variations in conditions may occur between investigation locations, and there may be special conditions pertaining to the site which have not been revealed by the investigation and which have not therefore been taken into account in the report. Where variations exist on site, additional studies and actions may be required. Tectonic’s opinions are based upon information that existed at the time that the study was performed. The passage of time, man-made or natural events, may alter the site conditions. It is understood that the Services undertaken allowed Tectonic to form an opinion of the actual conditions of the site at the time the site was visited and cannot be used to assess the effect of any subsequent changes in the quality of the site, or its surroundings, or any laws or regulations. Any assessments made in this report are based on the conditions indicated from published sources and the findings of the investigation described. Actual subsurface conditions may differ from those indicated in the report (e.g. between boreholes or test pits). No warranty is included, either express or implied, that the actual conditions will conform exactly to the assessments contained in this report. Where data supplied by the client or other external sources, including previous site investigation data, have been used, it has been assumed that the information is correct unless otherwise stated. No responsibility is accepted by Tectonic for incomplete or inaccurate data supplied by others. This report is provided for the sole use by the Client and its professional advisers. No responsibility whatsoever for the contents of this report will be accepted to any person other than the Client. Any use which a third party makes of this report, or any reliance on or decisions to be made based on it, is the responsibility of such third parties. Tectonic accepts no responsibility for damages, if any, suffered by any third party as a result of decisions made or actions based on this report. Rev 0 (October 2013)