geotechnical investigation, proposed grandstand … living centre/geotechnical... · football...

GEOTECHNICAL INVESTIGATION, PROPOSED GRANDSTAND AND STORAGE BUILDING, ST. FRANCIS XAVIER UNIVERSITY, ANTIGONISH, NOVA SCOTIA

Project No. 121620326

Prepared for: St. Francis Xavier University P.O. Box 5000 Antigonish NS B2G 2W5

Prepared by: Stantec Consulting Ltd. 2847 Old Highway 104 Antigonish NS B2G 2k7 Phone: (902) 863-5805 Fax: (902) 863-5806

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Table of Contents

1.0 INTRODUCTION ............................................................................................................. 1 1.1 GENERAL ............................................................................................................................ 1

2.0 SITE DESCRIPTION AND GEOLOGY ............................................................................... 1

3.0 INVESTIGATIVE PROCEDURES ....................................................................................... 2 3.1 GENERAL ............................................................................................................................ 2 3.2 BOREHOLES ........................................................................................................................ 2 3.3 SURVEYING ......................................................................................................................... 2 3.4 LABORATORY TESTING ...................................................................................................... 2

4.0 SUBSURFACE CONDITIONS ........................................................................................... 3 4.1 GENERAL ............................................................................................................................ 3 4.2 ROOTMAT/TOPSOIL ........................................................................................................... 3 4.3 FILL....................................................................................................................................... 3

4.3.1 Silty Clayey Sand ............................................................................................ 3 4.3.2 Silty Sand with Gravel ..................................................................................... 4

4.4 PEAT .................................................................................................................................... 4 4.5 CLAY ................................................................................................................................... 4 4.6 SILTY SAND WITH GRAVEL ................................................................................................. 4 4.7 CLAYEY SAND .................................................................................................................... 4 4.8 TILL ....................................................................................................................................... 5

4.8.1 Clayey Sand .................................................................................................... 5 4.8.2 Clay with Sand ................................................................................................ 5 4.8.3 Silty Sand .......................................................................................................... 5

4.9 BEDROCK ........................................................................................................................... 5 4.10 GROUNDWATER ................................................................................................................ 6

5.0 DISCUSSION AND RECOMMENDATIONS ..................................................................... 6 5.1 GENERAL ............................................................................................................................ 6 5.2 FILL PLACEMENT AND SETTLEMENT .................................................................................. 7 5.3 PILE FOUNDATIONS ........................................................................................................... 8

5.3.1 Piles General.................................................................................................... 9

6.0 CLOSURE ...................................................................................................................... 10


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LIST OF TABLES Table 1 Summary of Borehole Findings ...................................................................................... 3 Table 2 Summary of Rock Core Unconfined Compressive Strength and Correlated Unconfined Compressive Strength from Point Load Index Tests ........................................... 6 Table 3 Summary of Factored Geotechnical Axial Resistance at Ultimate Limit States .... 8

LIST OF APPENDICES APPENDIX A Statement of General Conditions

Symbols and Terms Used on Borehole and Test Pit Records Borehole Records BH1-2017 to BH4-2017 Grain Size Analyses Figure No. 1, Borehole Location Plan


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1.0 INTRODUCTION

1.1 GENERAL

Stantec Consulting Ltd. (Stantec) has been retained by St. Francis Xavier University (St. FX) to carry out a geotechnical investigation for a proposed new grandstand and storage building at the St. Francis Xavier University campus in Antigonish, Nova Scotia. The purpose of this geotechnical investigation was to assess the subsurface soil, bedrock and groundwater conditions at the site and to provide geotechnical recommendations to assist in planning for site preparation and foundation design.

The scope of work completed for this project included the following:

• Completion of a geotechnical field investigation consisting of four (4) boreholes; • A laboratory testing program; • Preparation of this report presenting the findings of the field investigation and laboratory

analyses, as well as comments and recommendations to aid with site preparation and foundation design.

This report has been prepared specifically and solely for the proposed project described herein and contains all of the findings of this investigation.

2.0 SITE DESCRIPTION AND GEOLOGY

The proposed grandstand and storage building are to be constructed east of the existing football field. The current ground surface elevation in the location of the proposed grandstand and storage building is lower than the elevation of the football field and will be raised to the level of the football field. Fills between 0.40 to 1.44 m are anticipated. The ground surface in the location of the proposed grandstand and storage building is grass covered and slopes to a low point in the middle with a maximum relief of 1.04 m taken from BH1-2017 to BH3-2017.

Based on available geological mapping issued by the Nova Scotia Department of Natural Resources (NSDNR Map 82-2), and our previous experience in the area, it is understood that the site is situated over Windsor Group - Hood Island Formation bedrock consisting of limestone, siltstone, gypsum, anhydrite and sandstone. Based on available surficial geology mapping issued by the Nova Scotia Department of Natural Resources (NSDNR Map 92-003), and our previous experience in the area, the natural overburden material in the area below any fill materials consists of silty/clayey glacial till.

Karst sinkholes can be present in this bedrock formation; however, we are not aware of any sinkholes in this area.


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3.0 INVESTIGATIVE PROCEDURES

3.1 GENERAL

The geotechnical investigation consisted of drilling four boreholes in locations selected by St. FX representatives. The field borehole drilling program was conducted between January 17 and February 1, 2017. Samples of the soil and bedrock were recovered and classified. Detailed logs of the soil and bedrock conditions encountered, and the sampling and testing carried out are given on the Borehole Records in the Appendix.

3.2 BOREHOLES

Boreholes were drilled using a drill-rig equipped for geotechnical sampling and testing. The depths of the boreholes ranged from 14.34 to 33.55 m below ground surface. The boreholes were logged by Stantec personnel. Each borehole was advanced using HW size casing. Soil samples were taken using conventional 50 mm split-spoon samplers while performing Standard Penetration Tests. The Standard Penetration Test (N-value) is used to determine the number of blows required to drive a 50 mm outer diameter, split-spoon sampler 300 mm into the soil using a standard fall height and weight. N-values can be used as an indication of relative density, and can also be used to estimate other soil parameters.

Bedrock was cored in two of the boreholes (BH1-2017 and BH3-2017) using an HQ size core barrel. The Rock Quality Designation (RQD) and recovery of the samples were measured and recorded. RQD is the ratio of the sum of the core recovered greater than 100 mm in length divided by the total core drilled, expressed as a percentage.

After drilling, field slotted, flexible 25mm PVC tubing was installed in BH1-2017 and BH4-2017 to permit groundwater level measurements. Groundwater levels were measured on April 17, 2017.

3.3 SURVEYING

At the request of St. FX, SNC-Lavalin surveyed borehole locations and elevations; elevations are referenced to Geodetic Datum. Borehole Locations are shown on Figure No. 1 in the Appendix.

3.4 LABORATORY TESTING

All soil and bedrock samples were taken to our Antigonish and Dartmouth laboratories for final visual assessment and classification testing. Laboratory testing was conducted on selected soil samples which included moisture contents, grain size analyses and Atterberg limits. In addition, unconfined compressive strength tests and point load tests were performed on bedrock core samples. The results of the laboratory testing performed are shown on the Borehole Records, summary tables, or are appended separately.


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Soil descriptions given in the borehole logs have been determined using ASTM D 2487, Standard Practice for Classification of Soils for Engineering Purposes - Unified Soil Classification System, and 2488, Standard Practice for Description and Identification of Soils - Visual-Manual Procedure.

4.0 SUBSURFACE CONDITIONS

4.1 GENERAL

The subsurface conditions encountered in the boreholes are described in detail on the appended Borehole Records.

In summary, the subsurface conditions at the boreholes generally consisted of a surficial rootmat/topsoil overlying fills, peat, clay, silty sand, native glacial till and bedrock. The glacial till is comprised of clayey sand to clay with sand and contained some gravel, occasional cobbles and occasional boulders. Bedrock is comprised of grey evaporite rock.

Details of the various soil and bedrock strata encountered at the borehole locations are provided in the following table and subsequent subsections.

Table 1 Summary of Borehole Findings

BH

Ground Surface

Elev. (m)

Thickness of Layer (m)

Glacial Till (m)

BEDROCK (m)

Groundwater (m)

Rootmat/ Topsoil FILL PEAT CLAY SILTY

SAND CLAYEY SAND

Depth to Surface

Elev. of Surface THICKNESS Depth Elev.

Depth Below Ground Surface

BH1-2017 13.29 0.30 3.06 - - - - 3.36 9.93 19.82 23.18 -9.89 12.55

BH2-2017 12.59 0.30 4.58 2.75 - - - 7.63 4.96 >15.86 - - -

BH3-2017 12.25 0.30 5.50 1.52 2.44 - 2.44 12.20 0.05 18.45 30.65 -18.40 -

BH4-2017 13.02 0.30 5.80 - - 3.56 - 9.46 3.56 >4.89 - - 2.38

Notes: 1) Elevations are Referenced to Geodetic Datum

4.2 ROOTMAT/TOPSOIL

A 0.30 m thick surficial layer of rootmat/topsoil was encountered at all borehole locations.

4.3 FILL

4.3.1 Silty Clayey Sand

A fill layer comprised of brown silty clayey sand with some gravel, organics and occasional cobbles and boulders was encountered below the rootmat/topsoil in all boreholes. The thickness of this fill layer ranged from 3.06 m (BH1-2017) to 5.50 m (BH3-2017).


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A grain size analysis performed on a sample of this material yielded 0% gravel, 63% sand, and 37% silt and clay sized particles. The moisture content of the samples tested ranged from 12 to 20%. Atterberg Limit testing indicated a 26% Liquid Limit, a 19% Plastic Limit, and a 7% Plasticity Index.

4.3.2 Silty Sand with Gravel

A fill layer comprised of brown silty sand with gravel was encountered below the silty clayey sand with some gravel fill in BH4-2017. The thickness of this fill layer was 1.52 m.

A grain size analysis performed on a sample of this material yielded 22% gravel, 55% sand, and 23% silt and clay sized particles. The moisture content of two samples tested were 17 and 13%.

4.4 PEAT

Peat was encountered under the silty clayey sand with some gravel fill in BH2-2017 and BH3-2017. The thickness of the peat was 2.75m and 1.52 m in BH2-2017 and BH3-2017, respectively. The moisture content of samples tested ranged from 39 to 103%.

4.5 CLAY

A layer comprised of grey/brown clay with sand and some organics was encountered below the peat in BH3-2017. The thickness of this layer was 2.44m.

A grain size analysis performed on a sample of this material yielded 0% gravel, 24% sand, and 76% silt and clay sized particles. The moisture content of a sample tested was 59%. Atterberg Limit testing indicated a 32% Liquid Limit, a 21% Plastic Limit, and a 11% Plasticity Index.

4.6 SILTY SAND WITH GRAVEL

A layer comprised of brown silty sand with gravel was encountered below the silty sand with gravel fill in BH4-2017. The thickness of this layer was 3.56 m.

Two grain size analyses performed on samples of this material yielded 16 and 22% gravel, 54 and 60% sand, and 30 and 17% silt and clay sized particles. The moisture content of samples tested ranged between 16 and 20%.

4.7 CLAYEY SAND

A layer comprised of brown clayey sand was encountered below the clay with sand and some organics in BH3-2017. The thickness of this layer was 2.55 m. Artesian water flow was encountered in this layer. The moisture content of samples tested ranged between 14 and 30%.


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4.8 TILL

4.8.1 Clayey Sand

Till comprised of brown clayey sand with some gravel and occasional cobbles and boulders was encountered below the silty clayey sand with some gravel fill in BH1-2017, below the peat in BH2-2017, below the clayey sand in BH3-2017 and below the silty sand with gravel in BH4-2017. The thickness of this till layer ranged from 6.40 m (BH3-2017) to 13.72 m (BH2-2017). BH4-2017 was terminated in this layer.

A grain size analysis performed on a sample of this material yielded 0% gravel, 51% sand, and 49% silt and clay sized particles. The moisture content of samples tested ranged between 10 and 24%. Atterberg Limit testing indicated a 42% Liquid Limit, a 25% Plastic Limit, and a 17% Plasticity Index.

4.8.2 Clay with Sand

Till comprised of brown clay with sand, some gravel and occasional gypsum cobbles and boulders was encountered below the clayey sand till in BH1-2017, BH2-2017 and BH3-2017. The thickness of this till layer ranged from 10.38 m (BH3-2017) to 12.50 m (BH1-2017). BH2-2017 was terminated in this layer.

A grain size analysis performed on a sample of this material yielded 0% gravel, 18% sand, and 82% silt and clay sized particles. The moisture content of samples tested ranged between 14 and 39%. Atterberg Limit testing indicated a 49% Liquid Limit, a 27% Plastic Limit, and a 22% Plasticity Index.

4.8.3 Silty Sand

Till comprised grey silty sand with some gravel was encountered below the clay with sand till in BH3-2017. The thickness of this layer was 1.67m.

A grain size analysis performed on a sample of this material yielded 0% gravel, 69% sand, and 31% silt and clay sized particles. The moisture content of a sample tested was 14%.

4.9 BEDROCK

Very poor to good quality, slightly to highly weathered, weak to strong grey evaporite rock was encountered in BH1-2017 and BH3-2017 at depths of 23.18 m and 30.65 m below ground surface, respectively. Rock quality designation (RQD) values measured on the recovered rock core varied from 0% to 87%. The results of unconfined compressive strength (Qu) testing performed on two samples of bedrock core were 16 MPa and 19 MPa. Correlated unconfined compressive strength from point load index (Ip) tests performed on samples of bedrock core varied from 18 MPa to 44 MPa. The results are summarized in Table 2.


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Table 2 Summary of Rock Core Unconfined Compressive Strength and Correlated Unconfined Compressive Strength from Point Load Index Tests

BH # Elevation (m) Qu (MPa)

Qu, inferred from Ip (MPa) Rock Type

1 -10.20 16 - Evaporite Rock

1 -11.42 19 - Evaporite Rock

3 -18.56 - 39 Evaporite Rock






4.10 GROUNDWATER

Groundwater levels were measured on April 17, 2017 at depths of 12.55 m and 2.38 m below ground surface in BH1-2017and BH4-2017, respectively. Groundwater levels are subject to seasonal influences, precipitation events, and alterations to the landscape.

5.0 DISCUSSION AND RECOMMENDATIONS

5.1 GENERAL

It is understood that the proposed grandstand and storage building will be constructed in the locations shown on Figure No. 1, Borehole Location Plan in the Appendix. The current ground surface elevation in the location of the proposed grandstand and storage building is lower than the elevation of the football field and will be raised to the level of the football field. Fills between 0.40 to 1.44 m are anticipated. Based on discussions with St. FX representatives the grandstands will be a frame system supported on a structural slab or a post and beam system. The proposed storage building will be a single story structure with no basement.

It is further understood that the planning for the grandstand and storage building is still in the preliminary stages and some key aspects of the design have not been confirmed. Therefore, only general comments are provided at this time. However, the recommendations provided herein would remain relevant and a review of the plans by our personnel should be completed as the design and planning for the grandstand and storage building progresses.

Based on the findings at the borehole locations, it is anticipated that the grandstand and storage building will be supported on piles driven into the native till. Spread footing foundations cast onto structural fill placed on the competent bearing soils are likely not feasible because of


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the average depth of excavation required to reach these soils would be in the order of 7.5 m. For planning purposes, therefore, we assume that site development will consist of driving piles to support the foundations. The following sections provide geotechnical recommendations to assist with planning and design of the foundations.

5.2 FILL PLACEMENT AND SETTLEMENT

The footprint of the proposed fill area should be stripped of topsoil and proof-rolled with a large sized (10 ton minimum) vibratory roller under the supervision of qualified geotechnical personnel prior to placing structural fill to increase the grade. Soft areas identified should be removed and replaced with structural fill. Existing underground services in this location may also have to be removed.

Imported structural fill should preferably consist of approved well graded granular fill and may consist of well graded pitrun or gravel such as NSTIR Type II gravel. Depending on construction conditions, other material may be suitable but should be approved by qualified geotechnical personnel prior to placement. The lift thickness used during placement of fill should be compatible with the compaction equipment and material type to ensure the required density throughout. Fill should be compacted throughout the lift thickness to a minimum of 100 percent of the material’s corrected maximum dry density, as determined in accordance with ASTM D698 (Standard Proctor).

Fills between 0.4 to 1.4 m (plus the thickness of the organic layer that will be removed) are anticipated. Increasing the grade will induce settlements in the existing fill, peat and native soils. Some of the settlement will occur as the area is raised and some will occur as time-dependent settlement. At present, the ground slopes to a low point between BH2-2017 and BH3-2017. New fill thicknesses will be largest in this area. A peat layer was encountered in BH2-2017 and BH3-2017 but not in BH1- 2017 and BH4-2017. The combination of the large fill thickness (approximately 1.44 m) and the presence of peat will result in more significant settlements near BH2-2017 and BH3-2017. Future settlements near BH1-2017 and BH4-2017 will be much smaller.

Calculations based on measured soil properties and thickness at the borehole locations and published correlations indicate that settlements in the area underlain by peat will be in the range of 150 to 200 mm. Areas without peat will experience very little settlement. Differential settlements could thus be nearly equal to the total settlement. Data on the actual extent of the peat is not sufficient to predict the distance over which the differential settlement would occur but it is estimated that it could be in the order of 15 m.

Based on the above, we recommend pile foundations for the structures and that all slabs be supported on the piles. A void may develop under the slabs due to longer-term secondary consolidation settlements.


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Filling near the existing running track and football field could cause settlement under the track and football field. It is understood that the track and football field will be re-surfaced in the near future and any settlement that occurs due to filling near them will be corrected when this work is completed.

5.3 PILE FOUNDATIONS

As previously noted, the principal native till in the boreholes is comprised of brown clayey sand with gravel and grey/brown clay with sand. Grey evaporite bedrock was encountered in two boreholes at depths of 23.18 and 30.65 m. Based on these conditions, we anticipate the use of driven steel H-piles or pipe piles developing end-bearing and frictional resistance in the native till.

We have conducted calculations to estimate the factored geotechnical axial resistance at ULS (using a factor of 0.4 based on CHBDC Clause 6.6.2.1) for various sizes of steel H-piles; the capacities relative to depth of penetration are presented in Table 3. For design, the depth of required penetration should be taken as the depth below the level of the native till; the frictional resistance of the fill, peat and other soils over the native till is ignored and must be considered as drag loads or negative skin friction.

Drag loads, induced by the settlement of the fill, peat and clay must be considered in the pile design. Drag loads would occur over the section of pile approximately between the top of the till and the final ground surface. The downward stress induced on a pile is equal to the average effective vertical stress (in this case between the top of the till and the ground surface) multiplied by the applicable soil/steel friction factor. Drag loads will vary over the site up a to a maximum of 1000 kN near BH3-2017. Once the layout and foundation details develop, we would be pleased to provide additional drag load details.

It should be noted that drag load increases structural load in the pile and therefore has to be accounted for when evaluating the structural capacity and settlement of the pile. Also drag load and transient live load do not combine and two separate loading cases must be considered: permanent load plus drag load or permanent load plus transient live load.

Table 3 Summary of Factored Geotechnical Axial Resistance at Ultimate Limit States

Penetration into Till (m)

Factored Geotechnical Axial Resistance at Ultimate Limit States (kN)

H-Pile 310x110 H-Pile 360x108 H-Pile 360x152

10 1200 1600 1650

15 1550 2050 2150


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For assessment of SLS, the settlement of piles driven to the appropriate penetrations to resist the design loads will be limited to the elastic compression of the pile; soil settlement will be negligible.

The piles should be driven with a hammer adequately sized to obtain the penetration required to achieve the design static compressive capacities. In general, a hammer having a rated energy in the range of 300 Joules/cm2 (1,500 ft-lb/in2) to 500 Joules/cm2 of steel cross sectional area is anticipated to achieve the required penetrations in the native till. Final hammer selection should be based on contractor experience and a drivability analysis. Jetting or pre-drilling techniques could be used to advance the piles, but their use may reduce the capacities.

Pile Driving Analyzer (PDA) testing should be carried out on a representative number of piles to confirm the estimated resistance provided for design. If capacities determined from PDA testing are less than the design capacities, further driving and continued PDA monitoring should be carried out until satisfaction is obtained that the required load capacity is being developed. Upon reaching anticipated penetration depths, piles may have to be allowed to set-up for a day or two to allow pore pressures from driving to dissipate to achieve the desired resistance.

5.3.1 Piles General

The group capacities for piles can be taken as the sum of the individual pile capacities provided the centre-to-centre spacing between piles is at least three pile diameters.

For frost protection, the base of pile caps should be founded a minimum of 1.2 m below finished grades.

It is recommended that full-time inspection be provided during pile installation. Comparison of pile tip elevations with penetration into native till should be carried out on an ongoing basis to ensure that the piles are installed to achieve required resistances. Caution should be used during driving of steel-H piles as they can be damaged by separation of the flanges and web when obstructions are encountered. Drive shoes should be used to protect the piles during installation. The contractor should provide full details on the method of installation and equipment prior to commencing the work.


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6.0 CLOSURE

Use of this report is subject to the Statement of General Conditions provided in the Appendix. It is the responsibility of St. Francis Xavier University, who is identified as “the Client” within the Statement of General Conditions, and its agents to review the conditions and to notify Stantec Consulting Ltd. should any of these not be satisfied. The Statement of General Conditions addresses the following:

• Use of the report • Basis of the report • Standard of care • Interpretation of site conditions • Varying or unexpected site conditions • Planning, design or construction

This report was written by Bradley Cleary, P.Eng. and reviewed by Dan McQuinn, P.Eng. We trust that the information contained in this report is adequate for your present purposes. If you have any questions about the contents of the report or if we can be of any other assistance please contact us at your convenience.

Yours very truly,

STANTEC CONSULTING LTD.

Bradley A. Cleary, M.A.Sc., P.Eng. Dan R. McQuinn, P.Eng. Senior Associate, Geotechnical Engineering Principal, Geotechnical Engineering [email protected] [email protected]


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Appendix A Statement of General Conditions

Symbols and Terms Used on Borehole and Test Pit Records Borehole Records BH1-2017 to BH4-2017

Grain Size Analyses Figure No. 1, Borehole Location Plan

SEPTEMBER 2013

STATEMENT OF GENERAL CONDITIONS USE OF THIS REPORT: This report has been prepared for the sole benefit of the Client or its agent and may not be used by any third party without the express written consent of Stantec Consulting Ltd. and the Client. Any use which a third party makes of this report is the responsibility of such third party. BASIS OF THE REPORT: The information, opinions, and/or recommendations made in this report are in accordance with Stantec Consulting Ltd.’s present understanding of the site specific project as described by the Client. The applicability of these is restricted to the site conditions encountered at the time of the investigation or study. If the proposed site specific project differs or is modified from what is described in this report or if the site conditions are altered, this report is no longer valid unless Stantec Consulting Ltd. is requested by the Client to review and revise the report to reflect the differing or modified project specifics and/or the altered site conditions. STANDARD OF CARE: Preparation of this report, and all associated work, was carried out in accordance with the normally accepted standard of care in the state or province of execution for the specific professional service provided to the Client. No other warranty is made. INTERPRETATION OF SITE CONDITIONS: Soil, rock, or other material descriptions, and statements regarding their condition, made in this report are based on site conditions encountered by Stantec Consulting Ltd. at the time of the work and at the specific testing and/or sampling locations. Classifications and statements of condition have been made in accordance with normally accepted practices which are judgmental in nature; no specific description should be considered exact, but rather reflective of the anticipated material behavior. Extrapolation of in situ conditions can only be made to some limited extent beyond the sampling or test points. The extent depends on variability of the soil, rock and groundwater conditions as influenced by geological processes, construction activity, and site use. VARYING OR UNEXPECTED CONDITIONS: Should any site or subsurface conditions be encountered that are different from those described in this report or encountered at the test locations, Stantec Consulting Ltd. must be notified immediately to assess if the varying or unexpected conditions are substantial and if reassessments of the report conclusions or recommendations are required. Stantec Consulting Ltd. will not be responsible to any party for damages incurred as a result of failing to notify Stantec Consulting Ltd. that differing site or sub-surface conditions are present upon becoming aware of such conditions. PLANNING, DESIGN, OR CONSTRUCTION: Development or design plans and specifications should be reviewed by Stantec Consulting Ltd., sufficiently ahead of initiating the next project stage (property acquisition, tender, construction, etc), to confirm that this report completely addresses the elaborated project specifics and that the contents of this report have been properly interpreted. Specialty quality assurance services (field observations and testing) during construction are a necessary part of the evaluation of sub-subsurface conditions and site preparation works. Site work relating to the recommendations included in this report should only be carried out in the presence of a qualified geotechnical engineer; Stantec Consulting Ltd. cannot be responsible for site work carried out without being present.

SYMBOLS AND TERMS USED ON BOREHOLE AND TEST PIT RECORDS – JULY 2014 Page 1 of 3

SYMBOLS AND TERMS USED ON BOREHOLE AND TEST PIT RECORDS

SOIL DESCRIPTION

Terminology describing common soil genesis:

Rootmat - vegetation, roots and moss with organic matter and topsoil typically forming a

mattress at the ground surface

Topsoil - mixture of soil and humus capable of supporting vegetative growth

Peat - mixture of visible and invisible fragments of decayed organic matter

Till - unstratified glacial deposit which may range from clay to boulders

Fill - material below the surface identified as placed by humans (excluding buried services)

Terminology describing soil structure:

Desiccated - having visible signs of weathering by oxidization of clay minerals, shrinkage cracks, etc.

Fissured - having cracks, and hence a blocky structure

Varved - composed of regular alternating layers of silt and clay

Stratified - composed of alternating successions of different soil types, e.g. silt and sand

Layer - > 75 mm in thickness

Seam - 2 mm to 75 mm in thickness

Parting - < 2 mm in thickness

Terminology describing soil types:

The classification of soil types are made on the basis of grain size and plasticity in accordance with the Unified

Soil Classification System (USCS) (ASTM D 2487 or D 2488) which excludes particles larger than 75 mm. For

particles larger than 75 mm, and for defining percent clay fraction in hydrometer results, definitions proposed by

Canadian Foundation Engineering Manual, 4th Edition are used. The USCS provides a group symbol (e.g. SM)

and group name (e.g. silty sand) for identification.

Terminology describing cobbles, boulders, and non-matrix materials (organic matter or debris):

Terminology describing materials outside the USCS, (e.g. particles larger than 75 mm, visible organic matter, and

construction debris) is based upon the proportion of these materials present:

Trace, or occasional Less than 10%

Some 10-20%

Frequent > 20%

Terminology describing compactness of cohesionless soils:

The standard terminology to describe cohesionless soils includes compactness (formerly "relative density"), as

determined by the Standard Penetration Test (SPT) N-Value - also known as N-Index. The SPT N-Value is described

further on page 3. A relationship between compactness condition and N-Value is shown in the following table.

Compactness Condition SPT N-Value

Very Loose <4

Loose 4-10

Compact 10-30

Dense 30-50

Very Dense >50

Terminology describing consistency of cohesive soils:

The standard terminology to describe cohesive soils includes the consistency, which is based on undrained shear

strength as measured by in situ vane tests, penetrometer tests, or unconfined compression tests. Consistency

may be crudely estimated from SPT N-Value based on the correlation shown in the following table (Terzaghi and

Peck, 1967). The correlation to SPT N-Value is used with caution as it is only very approximate.

Consistency Undrained Shear Strength Approximate

SPT N-Value kips/sq.ft. kPa

Very Soft <0.25 <12.5 <2

Soft 0.25 - 0.5 12.5 - 25 2-4

Firm 0.5 - 1.0 25 - 50 4-8

Stiff 1.0 - 2.0 50 – 100 8-15

Very Stiff 2.0 - 4.0 100 - 200 15-30

Hard >4.0 >200 >30


ROCK DESCRIPTION

Except where specified below, terminology for describing rock is as defined by the International Society for Rock

Mechanics (ISRM) 2007 publication “The Complete ISRM Suggested Methods for Rock Characterization, Testing

and Monitoring: 1974-2006”

Terminology describing rock quality:

RQD Rock Mass Quality Alternate (Colloquial) Rock Mass Quality

0-25 Very Poor Quality Very Severely Fractured Crushed

25-50 Poor Quality Severely Fractured Shattered or Very Blocky

50-75 Fair Quality Fractured Blocky

75-90 Good Quality Moderately Jointed Sound

90-100 Excellent Quality Intact Very Sound

RQD (Rock Quality Designation) denotes the percentage of intact and sound rock retrieved from a borehole of

any orientation. All pieces of intact and sound rock core equal to or greater than 100 mm (4 in.) long are

summed and divided by the total length of the core run. RQD is determined in accordance with ASTM D6032.

SCR (Solid Core Recovery) denotes the percentage of solid core (cylindrical) retrieved from a borehole of any

orientation. All pieces of solid (cylindrical) core are summed and divided by the total length of the core run (It

excludes all portions of core pieces that are not fully cylindrical as well as crushed or rubble zones).

Fracture Index (FI) is defined as the number of naturally occurring fractures within a given length of core. The

Fracture Index is reported as a simple count of natural occurring fractures.

Terminology describing rock with respect to discontinuity and bedding spacing:

Spacing (mm) Discontinuities Spacing

Bedding

>6000 Extremely Wide -

2000-6000 Very Wide Very Thick

600-2000 Wide Thick

200-600 Moderate Medium

60-200 Close Thin

20-60 Very Close Very Thin

<20 Extremely Close Laminated

<6 - Thinly Laminated

Terminology describing rock strength:

Strength Classification Grade Unconfined Compressive Strength (MPa)

Extremely Weak R0 <1

Very Weak R1 1 – 5

Weak R2 5 – 25

Medium Strong R3 25 – 50

Strong R4 50 – 100

Very Strong R5 100 – 250

Extremely Strong R6 >250

Terminology describing rock weathering:

Term Symbol Description

Fresh W1 No visible signs of rock weathering. Slight discoloration along major

discontinuities

Slightly W2 Discoloration indicates weathering of rock on discontinuity surfaces.

All the rock material may be discolored.

Moderately W3 Less than half the rock is decomposed and/or disintegrated into soil.

Highly W4 More than half the rock is decomposed and/or disintegrated into soil.

Completely W5 All the rock material is decomposed and/or disintegrated into soil.

The original mass structure is still largely intact.

Residual Soil W6 All the rock converted to soil. Structure and fabric destroyed.


STRATA PLOT

Strata plots symbolize the soil or bedrock description. They are combinations of the following basic symbols. The

dimensions within the strata symbols are not indicative of the particle size, layer thickness, etc.

Boulders

Cobbles

Gravel

Sand Silt Clay Organics Asphalt Concrete Fill Igneous

Bedrock

Meta-

morphic

Bedrock

Sedi-

mentary

Bedrock

SAMPLE TYPE

SS Split spoon sample (obtained by

performing the Standard Penetration Test)

ST Shelby tube or thin wall tube

DP Direct-Push sample (small diameter tube

sampler hydraulically advanced)

PS Piston sample

BS Bulk sample

HQ, NQ, BQ, etc. Rock core samples obtained with the use

of standard size diamond coring bits.

RECOVERY

For soil samples, the recovery is recorded as the length of the soil sample recovered. For rock core, recovery is

defined as the total cumulative length of all core recovered in the core barrel divided by the length drilled and

is recorded as a percentage on a per run basis.

N-VALUE

Numbers in this column are the field results of the Standard Penetration Test: the number of blows of a 140 pound

(63.5 kg) hammer falling 30 inches (760 mm), required to drive a 2 inch (50.8 mm) O.D. split spoon sampler one

foot (300 mm) into the soil. In accordance with ASTM D1586, the N-Value equals the sum of the number of blows

(N) required to drive the sampler over the interval of 6 to 18 in. (150 to 450 mm). However, when a 24 in. (610

mm) sampler is used, the number of blows (N) required to drive the sampler over the interval of 12 to 24 in. (300

to 610 mm) may be reported if this value is lower. For split spoon samples where insufficient penetration was

achieved and N-Values cannot be presented, the number of blows are reported over sampler penetration in

millimetres (e.g. 50/75). Some design methods make use of N-values corrected for various factors such as

overburden pressure, energy ratio, borehole diameter, etc. No corrections have been applied to the N-values

presented on the log.

DYNAMIC CONE PENETRATION TEST (DCPT)

Dynamic cone penetration tests are performed using a standard 60 degree apex cone connected to ‘A’ size

drill rods with the same standard fall height and weight as the Standard Penetration Test. The DCPT value is the

number of blows of the hammer required to drive the cone one foot (300 mm) into the soil. The DCPT is used as a

probe to assess soil variability.

OTHER TESTS

S Sieve analysis

H Hydrometer analysis

k Laboratory permeability

γ Unit weight

Gs Specific gravity of soil particles

CD Consolidated drained triaxial

CU Consolidated undrained triaxial with pore

pressure measurements

UU Unconsolidated undrained triaxial

DS Direct Shear

C Consolidation

Qu Unconfined compression

Ip

Point Load Index (Ip on Borehole Record equals

Ip(50) in which the index is corrected to a

reference diameter of 50 mm)

WATER LEVEL MEASUREMENT

measured in standpipe,

piezometer, or well

inferred

Single packer permeability test;

test interval from depth shown to

bottom of borehole

Double packer permeability test;

test interval as indicated

Falling head permeability test

using casing

Falling head permeability test

using well point or piezometer

ROOTMAT/TOPSOILLoose brown silty, clayey sand:FILL-some gravel-some organics-occasional cobbles andboulders

Compact to dense brown clayeysand: TILL-some gravel-occasional cobbles andboulders

Hard grey/brown clay withsand: TILL-some gravel-occasional gypsum cobbles andboulders

350

300

275

350

400

500

475

550

400

200

400

325

575

11

10

2

8

9

20

26

39

25

33

36

31

30

12.99

9.93

2.61

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

1

2

3

4

5

6

7

8

9

10

11

12

13

13.29

App'd__________Jul 21 2017 10:41:32

BOREHOLE RECORD

UNDRAINED SHEAR STRENGTH - kPa

W

DYNAMIC PENETRATION TEST, BLOWS/0.3m

10 20 30 40 50 60 70 80 90

P WW

STANDARD PENETRATION TEST, BLOWS/0.3m

WATER CONTENT & ATTERBERG LIMITS

20 40 60 80

L

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

BH SIZE

2017/02/01

TE

ST

S

121620326PROPOSED GRANDSTAND AND STORAGE BUILDING, ST. FX, NS

mm

SAMPLES

to

1 2

ST. FRANCIS XAVIER UNIVERSITY

Page of

WA

TE

R L

EV

EL

TY

PE

NU

MB

ER

OR

-RQ

D %

PROJECT No.

DE

PT

H(m

)

ELE

VA

TIO

N(m

)

OT

HE

R

2017/04/17 DATUM

SOIL DESCRIPTION

ST

RA

TA

PLO

T

DATES: BORING WATER LEVEL

RE

CO

VE

RY

N-V

ALU

E

CLIENT

LOCATION

2017/01/27

BH1-2017

HWGEODETIC

MB

H 7

/21/

17

BAC

Poor to good quality, slightly tohighly weathered, weak, greyevaporite rock: BEDROCK-occasional dark grey mudstonelaminations-occasionally vuggy

End of Borehole-Standpipe Installed

425

475

305

92%

95%

84/300mm

28%

87%

42

55

-9.89

-12.94

Qu

Qu

SS

SS

SS

HQ

HQ

14

15

16

17

18

App'd__________Jul 21 2017 10:41:44

BOREHOLE RECORD


W


10 20 30 40 50 60 70 80 90

P WW



20 40 60 80

L

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

BH SIZE

2017/02/01

TE

ST

S


mm

SAMPLES

to

2 2


Page of

WA

TE

R L

EV

EL

TY

PE

NU

MB

ER

OR

-RQ

D %

PROJECT No.

DE

PT

H(m

)

ELE

VA

TIO

N(m

)

OT

HE

R

2017/04/17 DATUM

SOIL DESCRIPTION

ST

RA

TA

PLO

T


RE

CO

VE

RY

N-V

ALU

E

CLIENT

LOCATION

2017/01/27

BH1-2017

HWGEODETIC

MB

H 7

/21/

17

BAC

ROOTMAT/TOPSOILLoose brown silty clayey sand:FILL-some gravel-some organics-occasional cobbles andboulders

Black PEAT

Compact brown clayey sand:TILL-some gravel-occasional cobbles andboulders

400

300

150

425

250

150

125

325

500

250

250

100

100

200

0

475

425

300

350

300

250

450

5

4

4

6

6

5

6

7

2

6

15

15

37

10

11

13

14

18

29

21

16

30

12.29

7.71

4.96

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

12.59

App'd__________Jul 21 2017 10:43:56

BOREHOLE RECORD


W


10 20 30 40 50 60 70 80 90

P WW



20 40 60 80

L

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

BH SIZE

2017/01/26

TE

ST

S


mm

SAMPLES

to

1 2


Page of

WA

TE

R L

EV

EL

TY

PE

NU

MB

ER

OR

-RQ

D %

PROJECT No.

DE

PT

H(m

)

ELE

VA

TIO

N(m

)

OT

HE

R

DATUM

SOIL DESCRIPTION

ST

RA

TA

PLO

T


RE

CO

VE

RY

N-V

ALU

E

CLIENT

LOCATION

2017/01/25

BH2-2017

HWGEODETIC

MB

H 7

/21/

17

BAC

Very stiff to hard grey/brownclay with sand: TILL-some gravel-occasional gypsum cobbles andboulders

End of Borehole

75

150

0

150

575

70/150mm

31

16

18

64

-8.76

-10.90

SS

SS

SS

SS

SS

23

24

25

26

27

App'd__________Jul 21 2017 10:44:8

BOREHOLE RECORD


W


10 20 30 40 50 60 70 80 90

P WW



20 40 60 80

L

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

BH SIZE

2017/01/26

TE

ST

S


mm

SAMPLES

to

2 2


Page of

WA

TE

R L

EV

EL

TY

PE

NU

MB

ER

OR

-RQ

D %

PROJECT No.

DE

PT

H(m

)

ELE

VA

TIO

N(m

)

OT

HE

R

DATUM

SOIL DESCRIPTION

ST

RA

TA

PLO

T


RE

CO

VE

RY

N-V

ALU

E

CLIENT

LOCATION

2017/01/25

BH2-2017

HWGEODETIC

MB

H 7

/21/

17

BAC

ROOTMAT/TOPSOILLoose brown silty, clayey sand:FILL-some gravel-some organics-occasional cobbles andboulders

Black PEAT

Soft to firm grey/brown CLAYwith sand-some organics

Very loose to compact brownclayey SAND

-encountered artesian flowbetween 10.68 and 11.90 mbelow ground surface

Compact to dense brown clayeysand: TILL-some gravel-occasional cobbles andboulders

475

425

425

450

400

400

350

600

475

600

150

600

300

450

100

350

0

250

250

475

300

425

PUSH

PUSH

5

11

12

11

5

5

8

9

11

11

6

17

0

3

10

15

11

23

29

33

11.95

6.45

4.93

2.49

0.05

S

S

S

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

ST

SS

ST

SS

SS

SS

SS

SS

SS

SS

SS

SS

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

12.25

App'd__________Jul 21 2017 10:46:45

BOREHOLE RECORD


W


10 20 30 40 50 60 70 80 90

P WW



20 40 60 80

L

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

BH SIZE

2017/01/24

TE

ST

S


mm

SAMPLES

to

1 2


Page of

WA

TE

R L

EV

EL

TY

PE

NU

MB

ER

OR

-RQ

D %

PROJECT No.

DE

PT

H(m

)

ELE

VA

TIO

N(m

)

OT

HE

R

DATUM

SOIL DESCRIPTION

ST

RA

TA

PLO

T


RE

CO

VE

RY

N-V

ALU

E

CLIENT

LOCATION

2017/01/18

BH3-2017

HWGEODETIC

MB

H 7

/21/

17

103103

BAC

Hard grey/brown clay withsand: TILL-some gravel-occasional gypsum cobbles andboulders

Very dense grey silty sand:TILL-some gravel

Very poor to poor quality,slightly to moderatelyweathered, medium strong tostrong, grey evaporite rock:BEDROCK

End of Borehole

350

550

475

500

475

500

125

500

425

100

55%

87%

59/150mm

112/458mm

60/150mm

0%

33%

35

41

39

56

60

56

46

-6.35

-16.73

-18.40

-21.30

S

S

Ip

Ip

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

HQ

HQ

23

24

25

26

27

28

29

30

31

32

33

34

App'd__________Jul 21 2017 10:46:56

BOREHOLE RECORD


W


10 20 30 40 50 60 70 80 90

P WW



20 40 60 80

L

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

BH SIZE

2017/01/24

TE

ST

S


mm

SAMPLES

to

2 2


Page of

WA

TE

R L

EV

EL

TY

PE

NU

MB

ER

OR

-RQ

D %

PROJECT No.

DE

PT

H(m

)

ELE

VA

TIO

N(m

)

OT

HE

R

DATUM

SOIL DESCRIPTION

ST

RA

TA

PLO

T


RE

CO

VE

RY

N-V

ALU

E

CLIENT

LOCATION

2017/01/18

BH3-2017

HWGEODETIC

MB

H 7

/21/

17

BAC

ROOTMAT/TOPSOILLoose brown silty clayey sand:FILL-some gravel-some organics-occasional cobbles andboulders

Loose to compact brown siltysand with gravel: FILL

Very loose to loose brown siltySAND with gravel

Compact to dense brown clayeysand: TILL-some gravel-occasional cobbles andboulders-occasional gypsum cobbles-450 mm boulder at 11.23 mbelow ground surface

End of Borehole-Standpipe Installed

500

400

450

400

475

575

250

400

450

350

50

75

250

400

475150

400

500

60/150mm

9

7

4

8

5

10

7

18

3

3

8

3

17

41

30

26

32

12.72

8.44

6.92

3.56

-1.33

S

S

S

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SSSS

SS

SS

1

2

3

4

5

6

7

8

9

10

11

12

13

14

1516

17

18

13.02

App'd__________Jul 21 2017 10:48:57

BOREHOLE RECORD


W


10 20 30 40 50 60 70 80 90

P WW



20 40 60 80

L

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

BH SIZE

TE

ST

S


mm

SAMPLES

1 1


Page of

WA

TE

R L

EV

EL

TY

PE

NU

MB

ER

OR

-RQ

D %

PROJECT No.

DE

PT

H(m

)

ELE

VA

TIO

N(m

)

OT

HE

R

2017/04/17 DATUM

SOIL DESCRIPTION

ST

RA

TA

PLO

T


RE

CO

VE

RY

N-V

ALU

E

CLIENT

LOCATION

2017/01/17

BH4-2017

HWGEODETIC

MB

H 7

/21/

17

BAC

Approved:

Unified Soil Classification System ASTM D 2487/2488

Gravel Sand Silt/ClayBH3-2017 SA4 2.1 - 2.7 m 0% 63% 37%

BH3-2017 SA12 7.9 - 8.5 m 0% 24% 76%

BH3-2017 SA20 14.3 - 14.9 m 0% 51% 49%

DEPTH (m)

Job No.: 121620326

Soil Fractions Soil Description

clayey SAND

Curve BOREHOLE/TESTPIT SAMPLE

clayey SAND

CLAY with sand

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0.0010.010.1110100

Perc

ent

Pass

ing

Grain Size in Millimetres

Gravel SandSilt and Clay

Coarse CoarseFine FineMedium

BAC

Approved:



BH3-2017 SA31 29.0 - 29.6 m 0% 69% 31%

BH4-2017 SA8 5.2 - 5.8 m 22% 55% 23%

DEPTH (m)

Job No.: 121620326


silty SAND with gravel


CLAY with sand

silty SAND

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0.0010.010.1110100

Perc

ent

Pass

ing




BAC

Approved:



BH4-2017 SA12 8.2 - 8.8 m 22% 60% 17%

Job No.: 121620326





DEPTH (m)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0.0010.010.1110100

Perc

ent

Pass

ing




BAC

HSHS

HSHS

HS

HSHS

HSHS

HSHS

HS

HS

HS

HSHS

ST

ST

PP

P

PP

P

P

P

P

P

P

P

P

P

P

P

0 10 20 40m

BAR SCALE

1:1000

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