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GEOTECHNICAL INVESTIGATION REPORT FOR PROPOSED RECONSTRUCTION
OF THE DFO-SLCC STORAGE BUILDING NIPIGON, ONTARIO
MARCH 24TH, 2017 TS-NO-027467
PREPARED FOR: DEPARTMENT OF FISHERIES AND OCEANS CANADA
SEA LAMPREY CONTROL CENTRE (DFO-SLCC) 1219 QUEEN STREET EAST
SAULT STE. MARIE, ONTARIO P6A 2E5 CANADA
3 Copies – Department of Fisheries and Oceans 1 Copy – DST Consulting Engineers Inc., Thunder Bay, ON
DST CONSULTING ENGINEERS INC.
Geotechnical Investigation Report Proposed Reconstruction of the DFO-SLCC Storage Building, Nipigon, Ontario DST Reference No.: TS-NO-027467 i
DST CONSULTING ENGINEERS INC.
Table of Contents
1 INTRODUCTION ................................................................................................................ 1
2 PROJECT DESCRIPTION .................................................................................................. 1
3 FIELD INVESTIGATION AND LABORATORY TESTING ................................................... 2
4 GEOTECHNICAL INVESTIGATION ................................................................................... 5
4.1 Methodology ................................................................................................................ 5
4.2 Laboratory Testing ....................................................................................................... 5
5 GEOTECHNICAL DESCRIPTION OF SUBSURFACE CONDITIONS ................................ 6
5.1 Soil .............................................................................................................................. 6
5.2 Topsoil ......................................................................................................................... 6
5.3 Sand ............................................................................................................................ 6
5.4 Groundwater ................................................................................................................ 6
6 GEOTECHNICAL INVESTIGATION - DISCUSSION AND RECOMMENDATIONS ............ 7
6.1 Foundation ................................................................................................................... 7
6.2 Shallow Foundation ..................................................................................................... 7
6.3 Strip Footings ............................................................................................................... 8
6.4 Slab-On-Grade Construction ........................................................................................ 9
6.5 Backfill Material ............................................................................................................ 9
6.6 Frost Protection ..........................................................................................................10
6.6.1 Frost Penetration Depth .................................................................................... 10
6.6.2 Frost Protection for Foundation Footing ............................................................ 10
6.7 Excavation ..................................................................................................................11
6.8 Dewatering .................................................................................................................11
6.9 Site Preparation and Grading ......................................................................................11
6.10 Pipe Bedding, Backfill and Drainage Requirement ......................................................12
6.10.1 Pipe Installations .......................................................................................... 12
6.10.2 Pipe Bedding ............................................................................................... 13
6.10.3 Trench Backfill and Compaction Standard ................................................... 13
7 CONCRETE SLAB ASSESSMENT ....................................................................................14
8 REFERENCES ..................................................................................................................19
9 LIMITATIONS OF REPORT ...............................................................................................20
Geotechnical Investigation Report Proposed Reconstruction of the DFO-SLCC Storage Building, Nipigon, Ontario DST Reference No.: TS-NO-027467 ii
DST CONSULTING ENGINEERS INC.
List of Tables
Table 3-1 Test Pit UTM Coordinates ...................................................................................... 4
Table 5-1 Test Pit groundwater elevations ............................................................................. 6
Table 6-1 Soil Profile and Geotechnical Parameter Used for Foundation Analysis ................. 7
Table 6-2 Geotechnical Resistances and Reactions for Strip Footings ................................... 8
Table 7-1 Concrete Cylinder Laboratory Test Results .......................................................... 16
List of Figures
Figure 3-1: View of the Site facing southwest at Storage Building Site, Nipigon, ON ................... 2
Figure 3-2: View of Test Pit 1 at DFO-SLCC Storage Building Site, Nipigon, ON ........................ 3
Figure 3-3: View of Test Pit 2 at DFO-SLCC Storage Building Site, Nipigon, ON ........................ 3
Figure 3-4: View of Test Pit 3 at DFO-SLCC Storage Building Site, Nipigon, ON ........................ 4
Figure 7-1: Concrete drilling equipment .................................................................................... 15
Figure 7-2: Concrete core completed and slab bedding material samples................................. 15
Figure 7-3: Concrete patching of concrete floor......................................................................... 16
Figure 7-4: View of Concrete Cylinder C1 at DFO-SLCC Storage Building Site, Nipigon, ON ... 17
Figure 7-5: View of Concrete Cylinder C2 at DFO-SLCC Storage Building Site, Nipigon, ON ... 17
Figure 7-6: Concrete floor crack ................................................................................................ 18
Figure 7-7: Detail - Concrete floor crack .................................................................................... 18
Appendices
LIMITATIONS OF REPORT ...................................................................................................... ‘A’ DESCRIPTION OF THE TERMS .............................................................................................. ‘B’ DRAWINGS - PROJECT SITE PLAN AND TEST PIT LOCATION PLAN ............................... ‘C’ ENCLOSURES ........................................................................................................................ ‘D’
Geotechnical Investigation Report Proposed Reconstruction of the DFO-SLCC Storage Building, Nipigon, Ontario DST Reference No.: TS-NO-027467 1
DST CONSULTING ENGINEERS INC.
1 INTRODUCTION
DST Consulting Engineers Inc. (DST) has been retained by the Department of Fisheries and
Oceans Canada - Sea Lamprey Control Centre (DFO-SLCC) to conduct a geotechnical
investigation for the proposed reconstruction of the DFO-SLCC storage building in Nipigon,
Ontario (“Site”). The footprint of the existing building is approximately 45 m2 and will be replaced
with a steel storage structure of 81 m2. The Site location is shown on Drawing No. 1 in Appendix
C. This report presents the results of the geotechnical investigation carried out in general
accordance with DST proposal dated October 28th, 2016.
This report presents the factual results of the geotechnical investigation and provides
geotechnical recommendations for the design and construction of the proposed reconstruction of
the DFO-SLCC storage building.
2 PROJECT DESCRIPTION
DFO-SLCC is proposing to replace an existing storage building with a footprint of approximately
45 m2 with a steel storage structure of 81 m2 in Nipigon, ON (Latitude: 49°1'12.51" N, Longitude:
88°15'13.02" W). If possible, DFO-SLCC is looking to extend the existing concrete pad to
accommodate the larger footprint of a new building. The proposed site is within the property of
CN Rail near the Township of Nipigon, and DFO-SLCC received authorization from CN Rail to
conduct a geotechnical investigation at the site.
Geotechnical Investigation Report Proposed Reconstruction of the DFO-SLCC Storage Building, Nipigon, Ontario DST Reference No.: TS-NO-027467 2
DST CONSULTING ENGINEERS INC.
3 FIELD INVESTIGATION AND LABORATORY TESTING
Before carrying out the field investigation, DST marked out the test pit locations at the Site. Field
investigation was carried out on October 28th, 2016 utilizing a hydraulic excavator (Model: JD
200D LC). The field investigation was supervised on a full-time basis by DST personnel.
The field investigation consisted of three (3) test pits outside the perimeter of newly proposed
building footprint. The test pits were excavated to depths ranging from 1.1 to 3.0 m below existing
grade in the locations shown on Drawing No. 1 (Appendix C). Representative disturbed soil
samples were obtained from the excavator bucket at regular intervals. The photos of the Site and
test pits are illustrated in Figures 3-1 to 3-4. Photos were taken during the field investigation by
DST personnel.
Figure 3-1: View of the Site facing southwest at Storage Building Site, Nipigon, ON
Geotechnical Investigation Report Proposed Reconstruction of the DFO-SLCC Storage Building, Nipigon, Ontario DST Reference No.: TS-NO-027467 3
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Figure 3-2: View of Test Pit 1 at DFO-SLCC Storage Building Site, Nipigon, ON
Figure 3-3: View of Test Pit 2 at DFO-SLCC Storage Building Site, Nipigon, ON
Geotechnical Investigation Report Proposed Reconstruction of the DFO-SLCC Storage Building, Nipigon, Ontario DST Reference No.: TS-NO-027467 4
DST CONSULTING ENGINEERS INC.
Figure 3-4: View of Test Pit 3 at DFO-SLCC Storage Building Site, Nipigon, ON
DST recorded test pit locations in Universal Transverse Mercator (UTM) coordinates (NAD 1983)
using a handheld GPS receiver (Table 3-1). Test Pit logs can be found in Appendix D.
Table 3-1 Test Pit UTM Coordinates
Location Elevation, m Easting Northing
TP1 99.9 408340 5430458
TP2 100.0 408349 5430455
TP3 99.7 408353 5430446
The test pit ground surface elevations were surveyed by DST personnel, using a local benchmark
with an assumed elevation of 100.00 m. The benchmark was located at 2.4 m south-east from
the north-west corner of the building on the concrete floor of the building (Appendix C - Drawing
1).
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4 GEOTECHNICAL INVESTIGATION
4.1 Methodology
Hand push cone penetration testing was conducted at Test Pit 3. This involved advancing a cone-
shaped probe into the soil and measuring the resistance to the cone penetration. Groundwater
conditions were observed and recorded during test pit excavations.
Soil samples were identified in the field, placed in labelled plastic bags and transported to DST’s
laboratory in Thunder Bay for further laboratory analysis.
4.2 Laboratory Testing
Soil samples returned to the laboratory were subject to visual examination and additional
classification by geotechnical engineer.
Selected soil samples were tested in the DST laboratory for natural moisture content and sieve
analyses. Laboratory results are presented on the Test Pit logs as well as on the grain size
distribution graph (Appendix D).
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5 GEOTECHNICAL DESCRIPTION OF SUBSURFACE CONDITIONS
5.1 Soil
Details of the subsurface conditions are given in the Test Pit logs (Appendix D) and the sections
below.
5.2 Topsoil
A topsoil layer was encountered at the surface in Test Pit 1 and Test Pit 3 locations with a
thickness ranging between 200 and 300 mm.
5.3 Sand
A layer of brown to grey sand with some to trace of gravel and trace of silt was encountered in all
test pits within the limits of excavation, the thickness of this sand layer is unknown. The sand layer
contains fine to coarse grained well-graded sand.
The sand material has a loose to compact condition with hand-pushed cone penetration data
indicated as 1000 kPa. Sieve analysis tests were conducted on soil samples from Test Pit 1 and
Test Pit 3 (Enclosure 4, Appendix D). The moisture content tests carried out for this sand material
resulted in moisture contents ranging from 2% to 7%.
5.4 Groundwater
All three test pits remained dry on completion and there was no sign of seepage in any of these
test pits. It should be noted that groundwater levels may fluctuate seasonally and in response to
climatic conditions.
Table 5-1 Test Pit groundwater elevations
Test Pit Groundwater Depth (m) Groundwater Elev. (m)
Test Pit 1 Dry on completion Lower than 96.9
Test Pit 2 Dry on completion Lower than 98.9
Test Pit 3 Dry on completion Lower than 97.2
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6 GEOTECHNICAL INVESTIGATION - DISCUSSION AND RECOMMENDATIONS
6.1 Foundation
The proposed reconstruction Site of the DFO-SLCC storage building is underlain by a sand layer
within the investigation depths of 1.1 to 3.0 m below existing grade. Based on the limited
information from the test pits, soil and/or bedrock types below the depths of 1.1 to 3.0 m existing
grade are unknown.
Based on the in situ and laboratory test results from this investigation, the following parameters
are suggested as design parameters for the soil type encountered in the test pits. The
geotechnical soil design parameters are summarized in Table 6-1.
Table 6-1 Soil Profile and Geotechnical Parameter Used for Foundation Analysis
Material Depth, m Bulk Unit Weight,
(kN/m3)
Internal drained friction angle (deg)
Interface Friction Angle, δ (deg)
Sand 0.0 –3.0 21 30 20
6.2 Shallow Foundation
Foundation design parameters are given for static, vertically and concentrically loaded
foundations in compression unless noted otherwise. Dynamic, lateral, eccentric and uplift design
parameters can be provided at request if applicable.
All foundation design recommendations presented in this report are based on the assumption that
an adequate level of construction monitoring during foundation excavation and installation will be
provided. An adequate level of construction monitoring is considered to be: a) for shallow
foundations, examination of all excavation surfaces prior to backfilling as to ensure the integrity
of the subgrade; and b) for earthwork, full-time monitoring and compaction testing.
A conventional foundation system utilizing strip footings founded on a compacted sand layer is
suitable for the structural loadings anticipated. A compacted granular base of engineered fill below
the footing shall be a minimum of 150 mm thick. Any topsoil or organic material encountered must
be removed. The bearing capacities were estimated for the ultimate limit state (ULS) and
serviceability limit state (SLS) for a maximum settlement of 25 mm (Table 6-2). The resistance at
ULS was calculated by applying load resistance factor of 0.5 according to the Canadian
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Foundation Engineering Manual.
6.3 Strip Footings
Strip Footing elements for the proposed building can be founded on the inorganic native sand
layer. Strip footings may be designed using the limit state static bearing pressures listed in Table
6-2. A total maximum length of 10 m was considered for the strip footing geotechnical resistances
estimate. For these estimated bearing pressures to be realized, soil cover of 0.2 m above the
footing is required as described below. Minimum and maximum footing widths of 0.2 m and 0.5
m are recommended, respectively. A minimum distance of one footing width is also required
between adjacent footings.
Table 6-2 Geotechnical Resistances and Reactions for Strip Footings
Depth of footing, D (m)
Width of Strip Footing, B (m)
Ultimate Bearing Capacity (kPa)
Factored Resistance at ULS (kPa)
Factored Reaction at SLS (kPa)
0.2
0.2 100 50 50
0.3 120 60 60
0.5 150 75 75
Any soft or weak soils such as peat below foundation areas, shown or not shown by the test pits
and which are encountered during construction should be excavated under the direction of the
geotechnical engineer to competent material and then backfilled either with Granular ‘B’ Type I
material compacted to 100% standard Proctor maximum dry density (SPMDD) or with a lean
concrete mix. The backfilling material should be compacted to 100% SPMDD and should be
placed and compacted immediately following excavation to design grades.
Bearing areas will require very careful preparation. Following excavation all bearing surfaces
should be cleaned of all organic, loose, disturbed, or slough material prior to concreting or placing
compacted backfill material. Bearing surfaces should be protected at all times from rain, freezing
temperatures and the ingress of groundwater before, during and after construction. Backfill
against foundation walls should consist of an engineered fill material. All foundation excavations
and bearing surfaces should be inspected by a qualified geotechnical engineer to confirm the
integrity of the bearing surface. All constructed foundations should be placed on unfrozen soils,
which should be at all times protected from frost penetration.
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6.4 Slab-On-Grade Construction
The floor slab designed and constructed as a slab-on-grade construction is considered feasible,
provided certain precautions are undertaken. The existing sand layer material is considered
suitable for supporting the slab-on-grade. Therefore, the floor slab may be designed and
constructed as a slab on grade placed on an engineered fill pad constructed on the native sand
layer. The engineered fill pad should be compacted to at least 98% SPMDD. Non-woven
geotextile should be used as separation between native soil and engineered fill.
Once the slab subgrade has been prepared, the floor slab may be constructed on a 150 mm thick
well packed bed of 19 mm clear stone or on OPSS Granular A compacted to 98% SPMDD.
The slab should be structurally independent from walls and columns which are supported on
foundations. This is to reduce any structural distress that may occur as a result of differential soil
movement. If it is intended to place any internal non-load bearing partitions directly on the slab-
on-grade, such walls should also be structurally independent from other elements of the building
founded on the conventional foundation system so that some relative vertical movement of the
walls can occur freely.
The subgrade beneath slab-on-grade should be protected at all times from rain, snow, freezing
temperatures, excessive drying and the ingress of water. This applies during and after the
construction period.
Some relative movement between floor slab-on-grade and adjacent walls or foundation and
differential movement within the slab should be anticipated. Generally, if the recommendations
outlined in this report are followed, these movements are estimated to be, less than 10 mm.
6.5 Backfill Material
Backfill against foundations and foundation walls should consist of non-frost susceptible
engineered fill material such as Granular B Types I or II. The existing native soil which consists
of sand material is considered to be non-frost susceptible and is suitable for use as backfill
material. Exterior backfill against foundation walls should be capped with an impervious layer
(existing native material is not suitable to be used as impervious material). It is anticipated that
the majority of material used for the impervious layer will have to be imported to the Site. The final
grade should be sloped to promote surface drainage away from the structure.
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6.6 Frost Protection
6.6.1 Frost Penetration Depth
Based on the graph prepared jointly by the Division of Building Research, National Research
Council, and the Atmospheric Environment Service, Dept. of the Environment, Canada for the
period 1931 and 1960 published data, for an 85% probability level, the design freezing index for
the Nipigon area has been estimated as 1,750o Celsius days (3,150°F days Fahrenheit). The
design depth of frost penetration for an area that has been kept clear of snow cover should be
taken as 2.9 m for sand soil cover. Frost penetration depth will vary with type of soil cover. The
whole investigation area of the Site is underlain by sand and therefore a 2.9 m frost penetration
depth should be assumed.
The Site is underlain by well-graded sand and none or minimal ground surface heaving is
expected. Pavement, drainage, underground services and side walk designs should include frost
protection consideration. Services such as sewer and water lines should be located below the
depth of frost penetration or be protected with synthetic insulation.
6.6.2 Frost Protection for Foundation Footing
The DFO-SLCC building is an unheated building. For the unheated isolated foundations, to
prevent frost heave of the underlying soils, the foundation should be placed with 2.9 m of soil
cover, underlain by a frost depth layer of non-frost susceptible material (granular soil with less
than 8% of fines/silt) or, if less soil cover is provided, foundations may be underlain with Styrofoam
HI insulation or equivalent.
The results of the sieve analyses carried out on three samples indicate that the soil profile in the
vicinity of the existing building consists of non-frost susceptible material up to the frost depth. The
foundation can be placed on native inorganic soil above frost level. For the conditions
encountered at the Test Pits TP1 to TP3, frost movements are expected to be negligible to none.
Nevertheless, under certain extreme precipitation conditions, where part of the soil saturates and
freezes, it is possible that the footing could be submitted to frost heave as much as 20 mm. In
order to mitigate such effects of the frost heave, for this option, which is the most practical, it is
important that the low content of silt (less than 8%) within the frost zone be confirmed at the time
of construction with 3 additional grainsize analyses. Should any zones with excess silt be
encountered (grain size less than 0.075 mm), these should be sub-excavated and replaced with
Granular ‘B’ Type 1 material compacted to 98% SPMDD.
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6.7 Excavation
Based on the Test Pit logs TP1 to TP3, the base of excavations will occur within the sand deposit.
Excavations must be undertaken in accordance with the requirements of the Occupational Health
and Safety Act of Ontario (OHSA). The subsurface soils are considered to be Type 3 and in
accordance with the OHSA, the excavation side slopes will have to be cut back at 1H:1V. Local
flattening of the side slopes may be required for excavations below the groundwater level, if any,
and in zones of persistent seepage. The stability of the excavation side slopes will be highly
dependent on the contractor’s methodology and ability to effectively dewater the excavation.
No surface surcharges should be placed closer to the edge of the excavation than a distance
equal to twice the depth of the excavation, unless the excavation support system has been
designed to accommodate such surcharge.
Attention should be paid to structures or buried service lines close to the excavation. A general
guideline is that if a line projected down, at 30 degrees from the horizontal from the base of
foundations of adjacent structures intersects the extent of the proposed excavation, underpinning
or special shoring techniques may be required to avoid damaging earth movements.
6.8 Dewatering
It is anticipated that excavations will not extend below the groundwater level and groundwater
control will not be a concern. However, if groundwater control becomes necessary during
construction, it may be achieved by conventional sump pump techniques.
It is to be noted that dewatering effort will depend on a number of factors, including excavation
depth, season and weather conditions, and the length of time the excavations are open. It should
be left to the contractor to determine the means and methods of dewatering necessary to meet
the project requirements and align with their construction methodology and schedule.
6.9 Site Preparation and Grading
The final Site grading should be provided to direct water to areas remote of the proposed
structure. Minimum landscape gradients of 2% are recommended to reduce the risk of runoff
ponding in localized areas or against the building.
Landscaping within a zone of approximately two metres of the exterior perimeter of any structure
should be graded to drain away from the structure at a minimum gradient of 3%. Downspouts
should be positively directed away from the building to beyond the building backfill.
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Subsurface drainage below the floor slab is not required, providing the interior floor elevation is
at least 100 mm higher than adjacent exterior grades and exterior surface drainage is maintained.
If this is not the case, then subsurface drainage should be provided.
Where drainage is required, perforated drainage pipes surrounded with clear stone are
recommended around the perimeter of the foundation. To prevent the ingress of fines into the
drainage stone, the stone should be surrounded with a non-woven geotextile.
Prior to general Site grading for pipe layout, any debris, existing improvements, vegetation, roots,
pavements, or rubble, should be removed and disposed outside the construction limits. Any
shrubs or trees should be completely removed and all roots larger than 0.60 cm diameter should
be grubbed out. The resulting disturbed zones should be properly excavated and backfilled with
compacted structural fill. All active or inactive utilities within the construction limits should be
identified for relocation, abandonment, or protection prior to grading.
The bottoms of any broad, mass excavation areas should be proof-rolled with a rubber-tired
loader or other heavy equipment to locate any soft or loose zones. Any loose/soft or otherwise
unsuitable areas should be removed or compacted in-place. If the disturbed zone is greater than
about 0.30 m in depth, in-place compaction will be difficult, and additional over-excavation and
compaction will be needed. Site preparation for pavement and equipment loading areas should
include over-excavation and re-compaction of native soils. Upon completion of the required over-
excavation and proof-rolling, fills and backfills should be placed and compacted to 95 % of
maximum density from the proctor compaction test result.
6.10 Pipe Bedding, Backfill and Drainage Requirement
6.10.1 Pipe Installations
Installation of services will likely occur in sand. Trenching and pipe installations should be carried
out expeditiously. Care should be taken to prevent excessive disturbance of the subgrade soils
during construction. Sufficient equipment should be available for timely installation to minimize
construction difficulties. Excavating only short trench sections at one time can minimize such
disturbances.
The possibility of bottom heave in the trench exists below the water table. Note that once heaved,
a trench base would be considered unsuitable for pipe support. The base of the excavation should
be closely monitored for vertical movements and disturbance. Backfilling of the trench should
proceed as soon as possible after excavation.
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6.10.2 Pipe Bedding
Pipe bedding should be in accordance with the following Ontario Provincial Standard Drawings
(OPSD) design standards for the class and size of pipe being used as well as manufactures
recommendations. Depending on the type of pipe, as well as on ground conditions (e.g.,
groundwater level, moisture content of the soils, etc.) at the time of construction, one or more of
the following OPSD design standards may be applicable:
OPSD 0802.010 Flexible Pipe Embedment and Backfill – Earth Excavation
OPSD 0802.030 Rigid Pipe Bedding, Cover and Backfill – Type 1 and 2 Soil – Earth
Excavation
OPSD 0802.031 Rigid Pipe Bedding, Cover and Backfill – Type 3 Soil - Earth Excavation
Other OPSD Standards or manufacturer requirements may apply to the construction of the buried
services and the designer should consult these as appropriate for the materials being employed.
It is recommended that the design include a minimum 300 mm of compacted bedding below the
pipe. In the case of over-excavation, the material to bring the trench back to the required subgrade
level should consist of a well graded granular material compacted to 95% of SPMDD.
The trench base should not be founded in or on organics. If organics are found at the base
elevation of a trench, the trench should be extended through the organics (for a width equal to
twice the depth plus the pipe diameter) and the grade restored, as noted above.
6.10.3 Trench Backfill and Compaction Standard
Compaction of the trench backfill will be necessary for the following reasons:
1. To control settlement of the trench fill;
2. To provide lateral support to the trench sidewall; and
3. To minimize soil loads on the pipe.
Inorganic soils at the Site can be used for trench backfill above the pipe levels provided it meets
the OPSS specification for backfill. Alternatively, Granular B Type I material could be used for the
back fill above the pipe levels.
Trench backfill within the footprint of the roadway or parking lot should be compacted to 95% of
standard Proctor maximum dry density for the full depth of the trench. Heavy compaction
equipment should not be used until at least 1 m of compacted backfill exists above the pipe.
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During backfilling, care should be taken to ensure the backfill proceeds in equal stages
simultaneously on both sides of the pipe. No frozen material should be used as backfill; neither
should the trench base be allowed to freeze. The quality and workmanship in the construction is
as important as the compaction standards themselves. It is imperative that the guidelines for the
compaction be followed for the full depth of the trench to achieve satisfactory performance. Clay
seal should be installed along the service trenches in accordance with OPSD 802.095.
7 CONCRETE SLAB ASSESSMENT
Two concrete core samples (C1 and C2) were obtained from the Site from the existing concrete
slab using a portable concrete drilling equipment shown in Figure 7.1, the thickness of the cores
and the concrete slab were measured on site. Also, the type of the material under the slab was
sampled and identified as engineered fill - sand and gravel (Figure 7.2). The concrete core
sampling and an excavation outside the building, beside the concrete slab determined that no
artificial insulation (Styrofoam) has been placed under the building. Concrete core C1 shows
evidence of reinforcing wire mesh for concrete.
The holes in the slab were backfilled with concrete (ready mix) as can be seen in Figure 7-3.
The locations on Site of the two cores samples taken are shown on Drawing No. 1 (Appendix C).
The lab test results are summarized below in Table 7-1. Note that only compressive strength
testing was completed on cylinder C2.
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Figure 7-1: Concrete drilling equipment
Figure 7-2: Concrete core completed and slab bedding material samples
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Figure 7-3: Concrete patching of concrete floor
The lab test results, thicknesses and quality of the cores sampled indicate that the concrete slab
is in good condition and it has of a suitable thickness for continued use as floor slab of a storage
building. The service loading to be applied to the concrete slab should be confirmed by a structural
professional engineer licenced in the Province of Ontario.
Table 7-1 Concrete Cylinder Laboratory Test Results
Core No.
Dry Wt. (g)
Bulk Unit Weight, (kN/m3)
Diameter (mm)
Height /thickness
(mm)
Testing Load (lb.)
Compressive Strength (MPa)
C1 1,774.3 21.90 100.5 105.9 - -
C2 1,832.6 21.29 104.0 90.3 58,220 27.58
The concrete core recovered do not have the required height to diameter ratio of 2 to 1 to obtain
a valid/certified concrete strength, however it gives a qualitative indication of the axial strength
resistance of the material.
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Figure 7-4: View of Concrete Cylinder C1 at DFO-SLCC Storage Building Site, Nipigon, ON
Figure 7-5: View of Concrete Cylinder C2 at DFO-SLCC Storage Building Site, Nipigon, ON
Geotechnical Investigation Report Proposed Reconstruction of the DFO-SLCC Storage Building, Nipigon, Ontario DST Reference No.: TS-NO-027467 18
DST CONSULTING ENGINEERS INC.
Observations of the surface conditions of the existing concrete slab indicate that its frost
performance has been relatively good with a few cracks (less than 1 mm).
Figure 7-6: Concrete floor crack
Figure 7-7: Detail - Concrete floor crack
Geotechnical Investigation Report Proposed Reconstruction of the DFO-SLCC Storage Building, Nipigon, Ontario DST Reference No.: TS-NO-027467 19
DST CONSULTING ENGINEERS INC.
8 REFERENCES
Braja M. Das, 2006, Principles of Geotechnical Engineering, Sixth Edition.
Canadian Geotechnical Society (2006). Canadian Foundation Engineering Manual.
Canadian Standards Association, July 2009, A23.1-09/A23.2-09, Concrete Materials and
Methods of Concrete Construction/Test Methods and Standard Practices for Concrete.
Ontario Building Code, 2006, Part 4.1.8.4, Site Properties.
Roy E. Hunt, 2005, Geotechnical Engineering Investigation Handbook, Second Edition.
Appendix A
LIMITATIONS OF REPORT
DST CONSULTING ENGINEERS INC.
L I M I T A T I O N S O F R E P O R TGEOTECHNICAL STUDIES
The data, conclusions and recommendations which are presented in this report,and the quality thereof, are based on a scope of work authorized by the Client.Note that no scope of work, no matter how exhaustive, can identify all conditionsbelow ground. Subsurface and groundwater conditions between and beyond thetestholes may differ from those encountered at the specific locations tested, andconditions may become apparent during construction which were not detected andcould not be anticipated at the time of the site investigation. Conditions can alsochange with time. It is recommended practice that DST Consulting Engineersbe retained during construction to confirm that the subsurface conditionsthroughout the site do not deviate materially from those encountered in thetestholes. The benchmark and elevations used in this report are primarily toestablish relative elevation differences between the testhole locations and shouldnot be used for other purposes, such as grading, excavation, planning,development, etc.
The design recommendations given in this report are applicable only to theproject described in the text and then only if constructed substantially inaccordance with details stated in this report. Since all details of the design maynot be known, we recommend that we be retained during the final stage to verifythat the design is consistent with our recommendations, and that assumptionsmade in our analysis are valid.
Unless otherwise noted, the information contained herein in no way reflects onenvironmental aspects of either the site or the subsurface conditions.
The comments given in this report on potential construction problems andpossible methods are intended only for the guidance of the designer. Thenumber of testholes may not be sufficient to determine all the factors that mayaffect construction methods and costs, e.g. the thickness of surficial topsoil or filllayers may vary markedly and unpredictably. The contractors bidding on thisproject or undertaking the construction should, therefore, make their owninterpretation of the factual information presented and draw their own conclusionas to how the subsurface conditions may affect their work.
Any results from an analytical laboratory or other subcontractor reported hereinhave been carried out by others, and DST Consulting Engineers Inc. cannotwarranty their accuracy. Similarly, DST cannot warranty the accuracy ofinformation supplied by the client.
DST CONSULTING ENGINEERS INC.
Appendix B
DESCRIPTION OF TERMS
DST CONSULTING ENGINEERS INC.
EXPLANATION OF TERMS USED IN REPORT
SPT ‘N’ VALUE: THE STANDARD PENETRATION TEST (SPT) N VALUE OF THE NUMBER OF BLOWS REQUIRED TO CAUSE ASTANDARD 51 mm O.D. SPLIT BARREL SAMPLES TO PENETRATE 0.3 m INTO UNDISTURBED GROUND IN A BOREHOLE WHENDRIVEN BY A HAMMER WITH A MASS OF 63.5 kg, FALLING FREELY A DISTANCE OF 0.76 m. FOR PENETRATION OF LESS THAN 0.3m N VALUES ARE INDICATED AS THE NUMBER OF BLOWS FOR THE PENETRATION ACHIEVED. AVERAGE N VALUE IS DENOTEDTHUS Ñ.
DYNAMIC CONE PENETRATION TEST (DCPT): CONTINUOUS PENETRATION OF A CONICAL STEEL POINT (51 mm O.D. 60° CONEANGLE) DRIVEN BY 475 J IMPACT ENERGY ON ‘A’ SIZE DRILL RODS. THE RESISTANCE TO CONE PENETRATION IS MEASUREDAS THE NUMBER OF BLOWS FOR EACH 0.3 m ADVANCE OF THE CONICAL POINT INTO THE UNDISTURBED GROUND.
SOILS ARE DESCRIBED BY THEIR COMPOSITION AND CONSISTENCY OR DENSENESSTEXTURAL CLASSIFICATION OF SOILS
BOULDERS COBBLES GRAVEL SAND SILT CLAY
GREATER THAN 200 mm 75 TO 200 mm 4.75 TO 75 mm 0.075 TO 4.75 mm 0.002 TO 0.075 mm LESS THAN 0.002 mm
COARSE GRAIN SOIL DESCRIPTION (50% GREATER THAN 0.075 mm)TERMINOLOGY TRACE OR OCCASIONAL SOME WITH ADJECTIVE (e.g. SILTY OR SANDY) AND (e.g. SAND AND SILT)
LESS THAN 10% 10 TO 20% 20 TO 30% 30 TO 40% 40 TO 60%
CONSISTENCY*: COHESIVE SOILS ARE DESCRIBED ON THE BASIS OF THEIR UNDRAINED SHEAR STRENGTH (CU) AN D SPT ‘N ’ V A LU E S AS FOLLOWSCU (kPa) 0 – 12 12 – 25 25 – 50 50 - 100 100 - 200 > 200
N (BLOWS / 0.3 m) <2 2 - 4 4 - 8 8 - 15 15 - 30 >30VERY SOFT SOFT FIRM STIFF VERY STIFF HARD
DENSENESS: C O H ESIO N LE S S SO IL S A R E D ESC R IB ED O N TH E B A SIS O N D EN S E N ES S A S IN D IC A TED B Y SPT ‘N ’ V A LU E SA S FO L LO W SN (BLOWS / 0.3 m) 0 – 5 5 – 10 10 – 30 30 – 50 > 50
VERY LOOSE LOOSE COMPACT DENSE VERY DENSE
ROCKS ARE DESCRIBED BY THEIR COMPOSITION AND STRUCTURAL FEATURES AND/OR STRENGTHRECOVERY: SUM OF ALL RECOVERED ROCK CORE PIECES FROM A CORING RUN EXPRESSED AS A PERCENT OF THE TOTAL LENGTH OF THECORING RUNMODIFIED RECOVERY: SUM OF THOSE INTACT CORE PIECES, 100 mm+ IN LENGTH EXPRESSED AS A PERCENTAGE OF THE LENGTH OF THE CORINGRUN.
THE ROCK QUALITY DESIGNATION (R.Q.D) FOR MODIFIED RECOVERY IS:R.Q.D (%) 0 – 25 25 – 50 50 – 75 75 – 90 90 – 100
VERY POOR POOR FAIR GOOD EXCELLENT
LEGEND OF RECORDS FOR BOREHOLES: SYMBOLS AND ABBREVATIONS FOR SAMPLE TYPESS SPLIT SPOON SAMPLE WS WASH SAMPLETW THIN WALL SHELBY TUBE SAMPLE AS AUGER (GRAB) SAMPLE
PH SAMPLER ADVANCED BY HYDRAULIC PRESSURE TP THIN WALL PISTON SAMPLE
WH SAMPLER ADVANCED BY SELF STATIC WEIGHT PM SAMPLER ADVANCED BY MANUAL PRESSURE
SC SOIL CORE RC ROCK CORE
WATER LEVEL
*HIERARCHY OF SOIL STRENGTH PREDICTION: 1) LABORATORY TRIAXIAL TESTING. 2) FIELD INSITU VANE TESTING.3) LABORATORY VANE TESTING. 4) SPT VALUES. 5) POCKET PENETROMETER.
Appendix C
DRAWINGS
DST CONSULTING ENGINEERS INC.
NIPIGON
RIVER
T
R
A
N
S
-C
A
N
A
D
A
H
IG
H
W
A
Y
0
SCALE
25 50 75 100 m
A
C
C
E
S
S
R
O
A
D
0 5 m
SCALE
TEST PIT
CONCRETE CORE
THUNDER BAY, ONTARIO
www.dstgroup.com
consulting engineers
TS
-N
O-027467 D
FO
S
torage B
uilding.dw
g
DRAWING 1
JANUARY 2017
Nipigon, Ontario
Proposed Reconstruction of Storage Building
Geotechnical Investigation
TESTPIT LOCATION PLAN
TS-NO-027467
Fisheries and Oceans
Department of
N
KEY PLAN
SITE
LEGEND
A
C
C
E
S
S
R
O
A
D
TP1
TP2
TP3
C1
C2
DFO-SLCC
STORAGE BUILDING
Appendix D
ENCLOSURES
DST CONSULTING ENGINEERS INC.
TOPSOIL
SAND, trace of GRAVEL, trace of SILT,grey, dry, fine to coarse
SAND, some GRAVEL, grey, dry, fine tocoarse
END OF TESTPIT at 3.0 m.
19 81 (0)
Cave at 2.5 m
Testpit remains dry oncompletionn
W
Sym
bol
300 600 1200
Wa
ter
Dat
a
DE
PT
H(m
) 120
Bulk Sample
'N' V
ALU
E
WI
PAGE 1 OF 1
8040
MATERIAL DESCRIPTION
ENCLOSURE 1
SA
MP
LE
TY
PEW
20
p
60
99
98
97
96
95
EL
EV
.(m
)
LOG OF TESTPIT TP1
% MOISTURE
SAMPLE TYPE LEGEND
VANE (kPa)
GR SA SI CL
& GRAINSIZEDISTRIBUTION (%)
REMARKS
900
CPT (kPa)60 90
1
2
3
4
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
4.8
Testpit DataMETHOD: EXCAVATORDATE: 10/28/2016COORDINATES: 5430458 m N, 408340 m E
DST REF. No.: TS-NO-027467CLIENT: DEPARTMENT OF FISHERIES AND OCEANSPROJECT: GEOTECHNICAL INVESTIGATIONLOCATION: NIPIGON, ONTARIOSURFACE ELEV.: 99.9 metres
DST CONSULTING ENGINEERS INC.605 HEWITSON STREET
THUNDER BAY, ON, P7B 5V5PH: 1-807-623-2929FX: 1-807-623-1792
Email: [email protected]: www.dstgroup.com
30
DE
PT
H(m
)
TE
ST
PIT
(S
TA
ND
AR
D)
TS
-NO
-027
467
DF
O S
TO
RA
GE
.GP
J D
AT
A T
EM
PLA
TE
.GD
T 4
/1/1
7
SAND, brown, dry, fine to coarse
SAND, trace of GRAVEL, trace of SILT,grey, dry, fine to coarse
END OF TESTPIT at 1.1 m. Testpit remains dry oncompletionn
W
Sym
bol
300 600 1200
Wa
ter
Dat
a
DE
PT
H(m
) 120
Bulk Sample
'N' V
ALU
E
WI
PAGE 1 OF 1
8040
MATERIAL DESCRIPTION
ENCLOSURE 2
SA
MP
LE
TY
PEW
20
p
60
99
98
97
96
EL
EV
.(m
)
LOG OF TESTPIT TP2
% MOISTURE
SAMPLE TYPE LEGEND
VANE (kPa)
GR SA SI CL
& GRAINSIZEDISTRIBUTION (%)
REMARKS
900
CPT (kPa)60 90
1
2
3
4
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
4.8
Testpit DataMETHOD: EXCAVATORDATE: 10/28/2016COORDINATES: 5430455 m N, 408349 m E
DST REF. No.: TS-NO-027467CLIENT: DEPARTMENT OF FISHERIES AND OCEANSPROJECT: GEOTECHNICAL INVESTIGATIONLOCATION: NIPIGON, ONTARIOSURFACE ELEV.: 100 metres
DST CONSULTING ENGINEERS INC.605 HEWITSON STREET
THUNDER BAY, ON, P7B 5V5PH: 1-807-623-2929FX: 1-807-623-1792
Email: [email protected]: www.dstgroup.com
30
DE
PT
H(m
)
TE
ST
PIT
(S
TA
ND
AR
D)
TS
-NO
-027
467
DF
O S
TO
RA
GE
.GP
J D
AT
A T
EM
PLA
TE
.GD
T 4
/1/1
7
TOPSOIL
SAND, trace of GRAVEL, trace of SILT,brown, loose to compact, dry, fine tocoarse
SAND, some GRAVEL, trace of SILT,brown, dry, fine to coarse
END OF TESTPIT at 2.5 m.
4
11
94
88
(2)
(1)
Testpit remains dry oncompletionn
W
Sym
bol
300 600 1200
Wa
ter
Dat
a
DE
PT
H(m
) 120
Bulk Sample
'N' V
ALU
E
WI
PAGE 1 OF 1
8040
MATERIAL DESCRIPTION
ENCLOSURE 3
SA
MP
LE
TY
PEW
20
p
60
99
98
97
96
95
EL
EV
.(m
)
LOG OF TESTPIT TP3
% MOISTURE
SAMPLE TYPE LEGEND
VANE (kPa)
GR SA SI CL
& GRAINSIZEDISTRIBUTION (%)
REMARKS
900
CPT (kPa)60 90
1
2
3
4
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
4.8
Testpit DataMETHOD: EXCAVATORDATE: 10/28/2016COORDINATES: 5430446 m N, 408353 m E
DST REF. No.: TS-NO-027467CLIENT: DEPARTMENT OF FISHERIES AND OCEANSPROJECT: GEOTECHNICAL INVESTIGATIONLOCATION: NIPIGON, ONTARIOSURFACE ELEV.: 99.7 metres
DST CONSULTING ENGINEERS INC.605 HEWITSON STREET
THUNDER BAY, ON, P7B 5V5PH: 1-807-623-2929FX: 1-807-623-1792
Email: [email protected]: www.dstgroup.com
30
DE
PT
H(m
)
TE
ST
PIT
(S
TA
ND
AR
D)
TS
-NO
-027
467
DF
O S
TO
RA
GE
.GP
J D
AT
A T
EM
PLA
TE
.GD
T 4
/1/1
7
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
1.18mm
Coarse
GRAVEL
Fine Coarse
19.0mm
BH
2.50
0.60
1.70
SYMBOL60
22
425µm
600µm
850µm
2"
PE
RC
EN
T
RE
TA
INE
D
75.0mm
" 3"
100
215 10 "
MINISTRY SIEVE DESIGNATION ( Imperial )
70
80
90
140 100 60 50
30 40 50
TP1
TP3
TP3
40
26.5mm
"
PE
RC
EN
T
PA
SS
ING
0
10
20
30
40
50
CLAY & SILTSAND
Fine
" 12
53µm
75µm
106µm
20 30 40 270 200
1 2 3 4 5
12
10 20 37.5mm
53.0mm
63.0mm
30 20 16 10 8 34" 1" 1
LEGEND
150µm
250µm
300µm
3 4
DEPTH
2.00mm
2.36mm
4.75mm
9.5mm
13.2mm
Medium
UNIFIED SOIL CLASSIFICATION SYSTEM
4 381
GRAIN SIZE IN MICROMETERS
CLAY & SILT
GRAIN SIZE DISTRIBUTION
SAND
T-T
IME
GR
AIN
SIZ
E T
S-N
O-0
2746
7 D
FO
ST
OR
AG
E.G
PJ
DA
TA
TE
MP
LAT
E.G
DT
30/
12/1
6
ENCLOSURE 4DST REF # TS-NO-027467
NIPIGON, ONTARIO