GEOTECHNICAL INVESTIGATION REPORT

Transcription

1 GEOTECHNICAL INVESTIGATION REPORT DH ACCOMODATE SPECIALIZED EQUIPMENT, DWYER HILL TRAINING CENTRE RICHMOND, ONTARIO Prepared for: Defence Construction Canada (DCC) Date: February 2016 Report No.: WSP Canada Inc Queensview Drive, Ottawa, ON K2B 8K2 Canada Phone: Fax:

2 TABLE OF CONTENTS 1 INTRODUCTION Context Project and Site Descriptions Objectives and Limitations 1 2 SITE INVESTIGATION Scope of work Investigation procedures Desk Study Field Investigation Laboratory Testing 3 3 SUBSURFACE GEOTECHNICAL CONDITIONS Soil Conditions Pavement Structure Fill Glacial till Auger Refusal/Bedrock Groundwater Conditions Summary 6 4 RECOMMENDATIONS General Seismic Considerations Liquefaction Potential Seismic Site Classification Frost Protection Foundations Slab on Grade Lateral Earth Pressures Foundation Wall Backfill 9 Geotechnical Investigation Dwyer Hill Training Centre Report No.:

3 4.8 Permanent Groundwater Control Backfilling and Compaction Site Services Corrosion and Cement Type Pavements Pavement Structures Frost Tapers Connections to existing pavements Construction Consideration Construction Dewatering Temporary Excavations Subgrade Preparation Winter Construction 13 5 GEOTECHNICAL PROJECT TEAM 14 APPENDICES Appendix A Appendix B Appendix C Appendix D Appendix E Drawings Borehole Logs and Core Photographs Corrosivity Testing Results Explanation of Terms used in Report Limitations of This Report Geotechnical Investigation Dwyer Hill Training Centre Report No.:

4 1 1 INTRODUCTION 1.1 CONTEXT WSP Canada Inc. (WSP) was retained by the Defense Construction Canada (DCC) to conduct a geotechnical investigation as part the design and construction of a new building at the Dwyer Hill Training Centre (DHTC) near Richmond, Ontario. The Terms of Reference (TOR) for this investigation are outlined in WSP s Proposal No. P dated December 4, 2015 and subsequent project correspondence. The purpose of the geotechnical investigation was to obtain subsurface information at the site by means of exploratory boreholes. This report presents the findings of the investigation and provides comments and recommendations related to the geotechnical aspects of the project. A topographic survey of the site has also been competed by WSP as part of the overall project and has been submitted separately. 1.2 PROJECT AND SITE DESCRIPTIONS The project site is located on the grounds of the Dwyer Hill Training Centre, located near Richmond, Ontario as shown in Drawing No.1. Based on the information provide in the Statement of Work (SOW) provide by DCC, it is understood that a new building is being proposed to house specialized equipment. This new building will be a one-storey above ground building with an approximate footprint of 9.8 metres (m) by 24.4 m (32 feet (ft) by 80 ft). It is assumed that this new building will be a slab-on-grade construction. The existing site consists of two single storey buildings and storage containers with associated asphalt paved parking areas and gravel surfaced areas between the storage containers. The topography of the land is relatively flat with the ground sloping to the north and west. The ground surface elevation at the southeast corner of the site is about approximately elevation m. The ground slopes downward to the north to approximately elevation m and to the west to approximately elevation m. 1.3 OBJECTIVES AND LIMITATIONS The current report was prepared at the request and for the sole use of DCC according to the specific terms of the mandate given to WSP. The use of this report by a third party, as well as any decision based upon this report, is under this party s sole responsibility. WSP may not be held accountable for any possible damages resulting from third party decisions based on this report. Furthermore, any opinions regarding conformity with laws and regulations expressed in this report are technical in nature; the report is not and shall not, in any case, be considered as a legal opinion. Information in this report is only valid for the borehole locations as described. Reference should be made to the Limitations of this Report, attached in Appendix E, which follows the text but forms an integral part of this document. Geotechnical Investigation Dwyer Hill Training Centre Report No.:

5 2 2 SITE INVESTIGATION 2.1 SCOPE OF WORK The scope of work for this assignment included: A desk study and review of existing geotechnical information in the general area; Laying out the boreholes and obtaining utility locates at the project site; Drilling of three exploratory boreholes within the project area; In-situ soil sampling and testing, including Standard Penetration Testing (SPT); Obtaining soil samples and rock core for additional review and laboratory testing; Laboratory testing; Geotechnical analysis; and Preparation of this report which presents the results of the investigation and provides geotechnical recommendations related to the design of the foundations, site services, building construction and pavements. 2.2 INVESTIGATION PROCEDURES The geotechnical investigation was carried out in January DESK STUDY Surficial geology maps indicate that the area is underlain by glacial till consisting of silty sand and gravel. Bedrock geology maps indicate the bedrock in the general area includes dolomite and limestone of the Oxford formation FIELD INVESTIGATION The field investigation was carried out on January 13 and 14, 2016 and included the drilling of three boreholes (BH16-1 to BH16-3) within the project area as shown on Drawing No. 2. The boreholes were advanced using a truck-mounted drill rig supplied and operated by George Downing Estate Drilling Limited (Downing) of Hawkesbury, Ontario. The boreholes were advanced using hollow-stem augers to depths ranging from 2.8 m to 4.7 m below the existing ground surface. Borehole BH16-2, after encountering auger refusal, was advanced to a depth of 5.9 m below the existing ground surface using NQ sized coring equipment. Soil samples and rock core retrieved during drilling were logged and visually classified in the field by a member of WSP s geotechnical staff. In-situ tests including Standard Penetration Testing (SPT) were carried out at regular intervals. Water level observations were made during drilling and in the open boreholes at the completion of the drilling operations. A piezometer was installed in borehole BH16-2 to allow for subsequent measurement of stabilized groundwater levels and long-term groundwater monitoring at the site. Boreholes BH16-1 and BH16-3 were backfilled, sealed just below the ground surface with bentonite and then the surface was patched with asphaltic concrete, where encountered. The borehole locations are shown in Appendix A. Borehole logs are included in Appendix B of this report. Geotechnical Investigation Dwyer Hill Training Centre Report No.:

6 LABORATORY TESTING Upon completion of drilling and in-situ testing, soil samples and rock core were returned to WSP s laboratory for further examination, classification and testing. A laboratory testing program, carried out on selected representative soil samples, included the determination of natural water content, grain size distribution, Atterberg limits (Plasticity) and Uniaxial Compressive Strength (UCS). The results of natural water content tests are included on the relevant borehole logs in Appendix B. The results grain size distribution, Atterberg limits and UCS testing are summarized on the individual borehole logs and presented in Appendix A. Geotechnical Investigation Dwyer Hill Training Centre Report No.:

7 4 3 SUBSURFACE GEOTECHNICAL CONDITIONS The subsurface soil profile at the site generally consists of an asphaltic pavement structure (where encountered) overlying fill and glacial till which is in turn underlain be bedrock. Auger refusal was encountered at depths ranging from 2.8 m to 4.7 m below the existing ground surface. Borehole 16-2 was extended past the depth of auger refusal by the use of NQ sized coring equipment. In borehole BH16-2, dolomite and limestone bedrock was encountered at a depth of 2.8 m below the existing ground surface. Descriptions of individual geological units are presented below. 3.1 SOIL CONDITIONS PAVEMENT STRUCTURE The existing pavement structure in the boreholes 16-1 and 16-2 within paved areas consisted of a layer of asphaltic concrete ranging between 60 millimeters (mm) and 115 mm in depth underlain by a granular road base, crushed sand and gravel with varying amounts of silt, that extended to a depth of 500 mm below the existing road surface. At borehole 16-3, this granular road base was also encountered at the existing ground surface and extended to 400 mm below the existing ground surface. Grain size curves for two selected samples of the granular road base are presented in Appendix A. A summary of these grain size distributions is also presented in the table below. Table 1 Results of Grain Size Analyses for Granular Road Base Borehole Sample No. Grain Size Distribution No. % Gravel % Sand % Fines BH16-1 SS BH16-2 SS The water content within the granular road base ranged between 7 percent and 8 percent FILL Fill was encountered below the pavement structure in boreholes BH16-1 and BH16-2 and below the granular road base in borehole This fill generally consists of gravelly silty sand. The fill was encountered to depths ranging from 1.5 m to 2.1 m below the existing ground surface. Grain size curves for two selected samples of the fill are presented in Appendix A. A summary of these grain size distributions is also presented in the table below. Geotechnical Investigation Dwyer Hill Training Centre Report No.:

8 5 Borehole No. Table 2 Results of Grain Size Analyses for Fill Sample No. Grain Size Distribution % Gravel % Sand % Fines BH16-1 SS BH16-3 SS The water content within the fill ranged between 8 percent and 13 percent GLACIAL TILL At all of the borehole locations, the fill is underlain by glacial till. The glacial till consists of a heterogeneous mixture of gravel, cobbles, and boulders in a matrix of silty sand and sandy silt with a trace of clay. The glacial till was fully penetrated in borehole 16-2 and the thickness of the glacial till in this borehole was 1.3 m. In the remaining boreholes, the glacial till was not fully penetrated but was proven for depths which vary from 1.5 m to 2.6 m. Standard penetration test N values for this material ranging from 9 blows to greater than 50 blow per 305 millimetres of penetration indicate a loose to very dense state of packing, although the higher N values could reflect the presence of cobbles and boulders, rather than the state of packing of the soil matrix. Grain size curves for three selected samples of the glacial till are presented in Appendix A. A summary of these grain size distributions is also presented in the table below. It should be noted that these grain size distribution tests were carried out on samples obtained from the split spoon sampler, which does not recover coarse gravel, cobble and boulder sized particles. Because of this the grain size distributions shown in Appendix A and the table below may be finer overall than some portions of the materials in the field. Table 3 Results of Grain Size Analyses for Glacial Till Borehole Grain Size Distribution Sample No. No. % Gravel % Sand % Fines BH16-1 SS BH16-2 SS BH16-3 SS The results of Atterberg limit testing carried out on two selected samples of the glacial till gave plasticity index values of 0 percent and 4 percent and liquid limit values of 14 percent and 18 percent. This indicates low plasticity fines. The measured water contents of samples within the glacial till ranged from 8 percent to 13 percent AUGER REFUSAL/BEDROCK Auger refusal was encountered in all three boreholes at depths ranging from 2.8 m to 4.7 m below the existing ground surface. Auger refusal may indicate the bedrock surface, however, it could also represent cobbles and/or boulders within the glacial till. Borehole BH16-2 was extended beyond the refusal depth using NQ sized diamond coring equipment. In this borehole, coring confirmed the presence of bedrock at and below the auger refusal depth. The rock encountered in the borehole BH16-2 consisted of fresh dolomite overlying fresh to slightly weathered dolomitic limestone. The Rock Quality Designation (RQD) of the dolomite bedrock was 84% indicating a rock quality of good. The Rock Quality Designation (RQD) of the dolomitic limestone bedrock was 73% indicating a rock quality of fair. Two samples of intact rock (obtained through coring) were tested in uniaxial compression and the result is summarized in the table below. Geotechnical Investigation Dwyer Hill Training Centre Report No.:

9 6 Table 4 Results of Intact Rock Strength Borehole No. Depth (m) Bedrock Description Unit Weight (kn/m 3 ) UCS (MPa) BH Dolomite BH Dolomitic Limestone GROUNDWATER CONDITIONS A piezometer was installed in borehole BH16-2 during the field investigation. The groundwater level within the piezometer was measured 8 days after completion of drilling (in January 2016) and found to be at 2.46 m below the existing road surface. It should be noted that the groundwater levels can vary and are subject to seasonal fluctuations as well as fluctuations in response to major weather events. 3.3 SUMMARY A summary of the soil conditions encountered at the various boreholes is presented in the table below. Table 5 Simplified Stratigraphy Simplified Stratigraphy (in metres) Borehole Road Glacial Notes Asphalt Fill Bedrock Base Till BH mm Auger Refusal at 4.7 m BH mm m BH Auger Refusal at 3.0 m Geotechnical Investigation Dwyer Hill Training Centre Report No.:

10 7 4 RECOMMENDATIONS 4.1 GENERAL This section of the report provides engineering guidelines related to the geotechnical design aspects of the project based on our interpretation of the available information described herein and project requirements. Contractors bidding on or undertaking the works should examine the factual results of the investigation, satisfy themselves as to the adequacy of the factual information for construction, and make their own interpretation of the factual data as it affects their proposed construction techniques, schedule, safety, and equipment capabilities. Reference should be made to the Limitations of this Report, attached in Appendix E, which follows the text but forms an integral part of this document. The general subsurface conditions encountered in the boreholes include an asphaltic concrete pavement structure overlying a layer of gravelly sand fill. The depth of the fill varied from 1.5 m to 2.1 m below the existing ground surface. Glacial till was encountered below the fill. Auger refusal was encountered in all three boreholes to depths varying from 2.8 m to 4.7 m. Dolomite and limestone bedrock were proven (cored) in one borehole below auger refusal. 4.2 SEISMIC CONSIDERATIONS LIQUEFACTION POTENTIAL A preliminary assessment for seismic liquefaction has been carried out for this site based on the subsurface conditions and the results of the SPT testing. Seismic liquefaction is the sudden loss in stiffness and strength of soil due to the loading effects of an earthquake. Liquefaction can cause significant settlements and structural failure. The assessment indicates that the soils at the site are not considered to be susceptible to liquefaction SEISMIC SITE CLASSIFICATION In accordance with Table A of the 2012 Ontario Building Code, the seismic site response for foundations placed on 3 m or more of either engineered fill or native glacial till would have a site classification of Class D. Foundations placed near bedrock would have a site classification of Class C provided that there is less than 3 metres of overburden materials between the underside of the foundation and the underlying bedrock surface. It is possible the site classification could be upgraded to Site Class A or Site Class B for foundations on bedrock. However, this would require a site-specific measurement of shear wave velocities. 4.3 FROST PROTECTION The depth of frost penetration for the site may be assumed to be 1.8 m. All foundation elements should therefore have a permanent soil cover of at least 1.8 m (or its thermal equivalent if artificial insulation is used). The soils within the frost depth are the granular road base, fill and the underlying glacial till. The road base and granular fill are considered to have a low to moderate susceptibility to frost heave. The underlying glacial till is considered to have a moderate susceptibility to frost heave. 4.4 FOUNDATIONS It is understood that the proposed building will include a single-storey slab-on-grade construction without a basement. Based on the results of the subsurface investigation, the proposed building could be supported on shallow spread footing foundations below frost depth penetration. At this depth, it is Geotechnical Investigation Dwyer Hill Training Centre Report No.:

11 8 anticipated that the underside of the footing level will be within either native glacial till or existing granular fill. For footing widths between 0.6 m and 1.5 m, the following bearing resistances may be assumed provided: The unfactored ultimate geotechnical bearing resistance can be taken as 600 kpa. A resistance factor of 0.5 should be applied to this value, yielding a factored bearing resistance of 300 kpa at ULS (Ultimate Limit States). The geotechnical resistance at the Serviceability Limit State (SLS) can be taken as 250 kpa. Provided that the foundation subgrade is properly prepared, and not unduly disturbed by construction activities, total and differential settlements associated with the above SLS resistance values are expected to be less than 25 mm and 20 mm, respectively. All bearing surfaces should be checked, evaluated and approved at the time of construction by a geotechnical engineer who is familiar with the findings of this investigation and the design and construction of similar projects prior to placement of any concrete, back fill, etc. Additional guidance related to bearing resistances can be provided based on preliminary designs. In particular, bearing resistances should be reviewed if the foundations are lower than previously indicated or if the foundation loads are too large for the assumed shallow foundation sizes. 4.5 SLAB ON GRADE For predictable performance of the floor slab, any existing topsoil should be removed from within the proposed building area and/or the existing fill material be recompacted to 98 percent of the material s standard Proctor maximum dry density using suitable vibratory compaction equipment. Provision should be made for at least 150 millimetres of Ontario Provincial Standard Specification (OPSS) Granular A to form the base for the floor slab. Any engineered fill required to raise the grade to the underside of the Granular A should consist of OPSS Granular B Type I or II. The underslab fill should be placed in maximum 300-millimetre thick lifts and should be compacted to at least 98 percent of the material s SPMDD using suitable vibratory compaction equipment. 4.6 LATERAL EARTH PRESSURES The lateral earth pressure acting on below-grade walls, retaining walls, etc. may be calculated using the following expression: Where: P = K = γ = h = q = P = K(γh+q) lateral earth pressure (kpa) acting at depth h earth pressure coefficient; for unrestrained walls and structures where some movement is acceptable (such as retaining walls) use a coefficient of active earth pressure (Ka) equal to 0.3, for restrained walls (such as basement walls) use the coefficient of earth pressure at rest (K0) equal to 0.5 the density of the backfill; use 21.5 kn/m 3 for compacted granular backfill the depth to the point of interest (m) the magnitude of any design surcharge at the ground surface; The above values assume free-draining granular backfill will be used. If this is not the case then the above values may need to be adjusted based on the soil type used, and water pressures should be considered in the calculation of lateral pressures. WSP can provide additional guidance based on actual building plans if required. The passive resistance offered by the foundation wall backfill soils could also be considered in evaluating the lateral resistance applied to the foundations. The magnitude of that lateral resistance will depend on the backfill materials and backfill conditions adjacent to the foundation walls. If the Geotechnical Investigation Dwyer Hill Training Centre Report No.:

12 9 backfill materials consist of compacted sand or sand and gravel (OPSS Granular B Type I) as discussed herein, then the passive resistance acting on the foundation wall may be taken as: where: σh(z) = Kp (γ z+q) σh(z) = lateral earth resistance applied to the foundation wall at depth z, kilopascals Kp = passive earth pressure coefficient, use 3.0 γ = unit weight of retained soil, use 21.5 kn/m 3 z = depth below top of wall, metres q = the magnitude of any design surcharge at the ground surface; This resistance is provided in unfactored format. Factoring of the calculated resistance value will be required if the design is being carried out using Limit States Design. Movement of the backfill and wall is required to mobilize the passive resistance. As a preliminary guideline, about 75 millimetres of movement would be required. Earth pressures will be higher under seismic loading conditions. In order to account for seismic earth pressures the total earth pressure during a seismic event (including both the seismic and static components) may be assumed to be: σh(z) = Ka γ z + (KAE Ka) γ (H-z) Where: σh(z) = the total earth pressure at depth z (kpa); Ka = the active earth pressure coefficient (0.3); γ = the unit weight of soil (21.5 kn/m 3 for granular fill or 19 kn/m 3 for native soils); KAE = the combined active earth pressure and seismic earth pressure coefficient (use 0.8); H = the total height of the wall (m) z = the depth below the top of the wall (m) The above earth pressure values (both static and seismic) are unfactored values. 4.7 FOUNDATION WALL BACKFILL Frost susceptible soil should not be used as backfill against exterior or unheated foundation elements (e.g., footing, foundation walls, pile caps, etc.). To avoid problems with frost adhesion and heaving, these foundation elements should be backfilled with one or more of the following: Non-frost-susceptible sand and/or gravel which meets that gradation requirements for OPSS Granular A or Granular B; 19 millimetre clear crushed stone having a unit weight not exceeding 21.5 kn/m 3, which is separated from other soils with a Class II non-woven geotextile having an FOS not exceeding 100 microns to prevent loss of adjacent sand, or silty soils into the clear stone. It should be noted that the use of clear stone as foundation backfill may lead to unfavourable growing conditions for plant matter placed in overlying topsoil. In areas where pavement or other hard surfacing will be in contact with the buildings, differential frost heaving could occur between the granular fill (if sand or crushed stone is used) and other areas. To reduce this differential heaving, the backfill adjacent to the wall should be placed to form a frost taper. The frost taper should be brought up to pavement subgrade level from 1.5 metres below finished exterior grade at a slope of 3 horizontal to 1 vertical, or flatter, away from the wall. The fill should be placed in maximum 300-millimetre thick lifts and should be compacted to at least 95 percent of the material s standard Proctor maximum dry density using suitable vibratory compaction equipment. Geotechnical Investigation Dwyer Hill Training Centre Report No.:

13 PERMANENT GROUNDWATER CONTROL The groundwater level at the site was found to be at about elevation m (2.5 m below the existing ground surface). If basements, sumps or other open below grade structures are planned below this elevation, they could intercept the groundwater table and should be provided with adequate drainage. Once the basement, sump and other below grade elevations are determined, the need for permanent groundwater control should be reviewed during detailed design. Basement drainage, however would typically include sub-drains below the basement floor and perimeter drains around the exterior of the basement. Based on the water staining on the fractures observed on the rock core retrieved during the current investigation significant amounts of water maybe present below the groundwater elevation. 4.9 BACKFILLING AND COMPACTION Backfill for foundation excavations and any below grade structures should comprise free draining OPPS Granular A or Granular B materials. Backfill should be placed in shallow lifts, not exceeding 200 mm loose thickness, and compacted to 98% SPMDD where it is supporting any structures or services, or 95% in other areas. The suitability of imported materials should be confirmed prior to placement from both a geotechnical and environmental perspective. The existing soils at the site generally do not meet the requirements for OPSS Granular A or Granular B. However, portions of the existing soils at the site are adequate for use as general earth fill, but may require moisture conditioning (either wetting or drying) prior to placement and compaction. To avoid damaging or laterally displacing the structures, care should be exercised when compacting fill adjacent to new structures. Heavy equipment should be kept a minimum of 1 m away from the structure during backfilling. The 1 m width adjacent to the wall should be compacted using hand-operated equipment unless otherwise authorized SITE SERVICES Excavations up to approximately 2.8 m below the existing ground surface would be primarily within the existing granular fill and underlying glacial till, which may contain cobbles and boulders. Excavations deeper than this may extend into a variety of materials ranging glacial till, cobbles and boulders and bedrock. Details of the proposed site services are not available at this time; however it is assumed that they will include localized trenches throughout the site. Trenches within overburden materials can be temporarily supported using sloped excavations (see Section ) or trench boxes. Bedrock removal may be required for some site services for this project. Mechanical methods of rock removal (such as hoe ramming), can likely be carried out for depths of about one metre, however, this work may be slow and tedious. Bedding for site services should be in accordance with the relevant OPSD standard drawing and would typically consist of Granular A compacted to 95% SPMDD. Where wet or disturbed conditions are encountered in the base of the trench it may be necessary to over-excavate and replace unsuitable soils with compacted granular fill to provide a stable sub-grade for the bedding. The use of clear stone as a bedding and cover material is not recommended as the finer particles of the native soils and backfill may migrate into the voids of the clear stone, resulting in loss of pipe support. Cover material above the spring line should consist of Granular A or Granular B material with a maximum particle size of 25 mm. Cover material should be compacted to a minimum of 95% SPMDD. Backfill may consist of additional granular fill, or the stiff weathered silty clay and should be compacted to 95% SPMDD (98% if below structures). Where backfill is below paved areas (such as access lanes Geotechnical Investigation Dwyer Hill Training Centre Report No.:

14 11 and parking lots) and is within the frost depth, the backfill profile (above the minimum cover required) in the trench should be made to match the native soils on either side as much as is practical in order to minimize the potential for differential frost heave. Any service trenches which extend below the water table should have clay cut-offs installed across the trench at regular intervals (typically every 100 m) to prevent the trench acting as a drain and lowering the groundwater table in the general area. These cut-offs should extend the full width of the trench and must completely penetrate the bedding, cover and any other granular materials in the trench. The above are general guidelines for typical site services. All service installations should be completed in accordance with the relevant OPSS s and OPSD s for the particular application and size. WSP can provide additional review during detailed design based on the actual services proposed if required CORROSION AND CEMENT TYPE Two samples were submitted to Exova Environmental Ontario for testing related to soil corrosivity and potential exposure of concrete elements to sulphate attack. The results of these tests are included in Appendix C and summarized in the table below. Borehole/ Sample No. Table 6 Results of Soil Corrosivity Testing Electrical Resistivit Chloride Soil Type Conductivity y (%) (ms/cm) (ohm-cm) ph Sulphate (%) BH16-1 / SS-4 Glacial Till , <0.01 BH16-2 / SS-2 Existing Fill < , The soil resistivity values measured in the existing granular fill and native glacial till soils suggest a moderately corrosive environment for buried steel elements. These values must be taken into consideration during designed below-grade steel elements, such as piling and underground services. The test results indicate a low soluble sulphate content and sulphate resistant Portland cement is not required PAVEMENTS PAVEMENT STRUCTURES Detailed traffic loads have not been provided at this time, however based on the subsoil conditions encountered, conventional asphaltic (flexible) pavement designs are likely to be appropriate for normal paved parking areas and driveways. Based on the results of this investigation and experience, the following asphaltic pavement designs are recommended for various traffic loadings: Pavement Layer Table 7 - Recommended Pavement Structure Thickness Light Duty Traffic (Cars and Light Trucks) Heavy Truck Loading (Delivery Trucks, Fire Routes, Access Roads, etc.) Asphaltic Concrete OPSS Granular A Base Pulverized Pavement 30 mm SP12.5 Surface Course 50 mm SP19.0 Binder Course 50 mm SP12.5 Surface Course 70 mm SP19.0 Binder Course 150 mm 150 mm 250 mm 250 mm Geotechnical Investigation Dwyer Hill Training Centre Report No.:

15 12 Traffic data has not been provided at this stage, however a Traffic Category of Level B is assumed to be adequate for a low-volume road. The asphaltic cement should be PG A functional design life of eight to ten years has been used to establish the flexible pavement recommendations. This represents the number of years to the first rehabilitation, assuming regular maintenance is carried out. If required, a more refined pavement structure design can be performed based on specific traffic data and design life requirements provided by the client. The long term performance of the pavement is highly dependent upon the subgrade support conditions. Stringent construction control procedures should be maintained to ensure uniform subgrade moisture and density conditions are achieved. In addition, the need for adequate drainage cannot be overemphasized. The finished pavement surface and underlying subgrade should be free of depressions and should be sloped to provide effective surface drainage toward catch basins. Surface water should not be allowed to pond adjacent to the outside edges of pavement areas. Subdrains can also be placed at catch basins and along curb lines to further improve sub-surface drainage. As part of the subgrade preparation, proposed parking areas and access roadways should be stripped of topsoil and other obvious objectionable material. Fill required to raise the grades to design elevations should conform to backfill requirements outlined in previous sections of this report. The subgrade should be properly shaped, crowned then proof-rolled in the full time presence of a representative of this office. Soft or spongy subgrade areas should be sub-excavated and properly replaced with suitable approved backfill compacted to 98% SPMDD. Base and sub-base layers should be compacted to 100% of SPMDD. The most severe loading conditions on light-duty pavement areas and the subgrade may occur during construction. Consequently, special provisions such as restricted access lanes, half-loads during paving, etc., may be required, especially if construction is carried out during unfavourable weather. If the new facility requires the use of concrete aprons or paving, additional recommendations can be provided FROST TAPERS To maintain frost heave compatibility between the new and existing roadway, frost tapers should be provided at the end of the new roadway in general accordance with OPSD or The frost tapers should be 3H:1V longitudinally within the granular subbase either up or down to match existing based on the assumption that some differential frost movement can be accommodated by routine maintenance and re-grading of the gravel surface CONNECTIONS TO EXISTING PAVEMENTS At the project limits, the new pavement structure should be continued to the end of rounding. From that point, the subbase thickness can be tapered to match the side road/ entrance pavement structure by sloping the subgrade up at 3 horizontal to 1 vertical to match the side road/entrance subgrade level. All tie-ins should include frost tapers between the existing pavement structures and the new pavement. Longitudinal connections with the existing pavement structure should be milled back a distance of 300 mm and the depth of milling should match the new asphaltic concrete surface course. A tack coat should be provided between the new surface course placed over the milled surface. The lower binder course of the new construction should be butt jointed to the existing asphaltic concrete 4.13 CONSTRUCTION CONSIDERATION CONSTRUCTION DEWATERING The groundwater level at the site was found to be at approximately 2.5 m below the existing surface elevation (Elevation m). For excavations above the water table and slightly below (less than 0.5 Geotechnical Investigation Dwyer Hill Training Centre Report No.:

16 13 m) the water table, it is likely that seepage into the excavations can be managed using properly filtered sumps, ditches, etc. For deeper excavations, additional or more complex dewatering may be required. WSP can provide additional guidance based on the size and depth of the excavation, if required during detailed design. The need for Ministry of Environment (MOE) Permit to Take Water (PTTW) is not anticipated at this time provided excavations remain at or above the groundwater table and dewatering operations are kept to less than 50,000 litres/day. This should be reviewed during detailed design based on the actual excavation details TEMPORARY EXCAVATIONS All excavations should be carried out in accordance with the most recent Occupational Health and Safety Act (OHSA). Part III of Ontario Regulation 213/91 deals with excavations. The soils within the expected excavation include fill and native glacial till. For preliminary planning purposes the existing fill and glacial till can be classified as a Type 3 Soil above the groundwater table (or depth of watering) and Type 4 soils below the groundwater table (or depth of watering). These classifications must be reviewed and confirmed by a qualified person during excavation. Excavations within Type 3 soil require side slopes with a minimum gradient of 1 horizontal to 1 vertical and excavations within Type 4 soil require side slopes of 3 horizontal to 1 vertical. If limited space is available then a temporary shoring system may be required. Once the location of the building and the floor elevation are determined the need for vertical shoring should be reviewed. The type of shoring to be used depends on the permissible movement of the shoring. The design of any the shoring system must be carried out by a professional engineer and take into consideration the effect of the excavation upon the neighbouring buildings and structures. The contractor is typically responsible for the detailed design of temporary shoring. If required, WSP can provide additional guidance based on preliminary excavation plans, depths, etc. during the detailed design phase of the project SUBGRADE PREPARATION The geotechnical bearing resistances provided in Section 4.4 assume that the foundation soils will not be disturbed by construction activities. Proper de-watering and protection of the exposed subgrade will be important to the construction of the foundations. All excavated surfaces should be kept free of frost, water, etc. during the course of construction. All excavated surfaces should be inspected by a qualified geotechnical engineer who is familiar with the findings of this investigation and the design and construction of similar structures. The foundations soils at the site are expected to be sensitive to disturbance from ponded water and construction traffic if the subgrade for the foundations and basement floor slab is exposed for a prolonged duration and/or exposed to construction traffic then placement of a mud slab directly on the subgrade may be required to protect the subgrade from these elements WINTER CONSTRUCTION In the event that construction is required during freezing temperatures, the frost susceptible subgrade below the footings should be protected immediately from freezing using straw, propane heaters, polystyrene insulation, insulated tarpaulins, or other suitable means that prevent the underlying soil from freezing, which could cause frost heave. Geotechnical Investigation Dwyer Hill Training Centre Report No.:

17 14 5 GEOTECHNICAL PROJECT TEAM WSP Canada Inc. Project Manager Project Director Site Investigation Geotechnical Laboratory Testing Bruce Goddard, P.Eng. Chris Hendry P. Eng., M. Eng. Derek Robertson W.A.McLaughlin, Geo. Tech., C. Tech Contractors Downing Estate Drilling Report prepared by: Reviewed by: Bruce Goddard P. Eng. Senior Geotechnical Engineer Chris Hendry P. Eng., M. Eng. Senior Geotechnical Engineer Geotechnical Investigation Dwyer Hill Training Centre Report No.:

18 DRAWINGS

19 N Project Area 0 m 200 m 400 m Client: Project#: DWG #: Drawn: Date: Size: Defence Construction Canada BDG CH Approved: January 2016 Scale: N. T. S. Letter Rev: 0 Title: Project: Site Location Plan Geotechnical Investigation Dwyer Hill Training Centre, Richmond, ON

20 N BH 16-3 BH 16-1 BH m 25 m 50 m Client: Project#: DWG #: Drawn: Date: Size: Defence Construction Canada BDG CH Approved: January 2016 Scale: N. T. S. Letter Rev: 0 Title: Project: Borehole Location Plan Geotechnical Investigation Dwyer Hill Training Centre, Richmond, ON

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24 BOREHOLE LOGS AND CORE PHOTOGRAPHS

25 LOG OF BOREHOLE 16-1 Project: Specialized Equipment Accommodation, DHTC Client: Defense Construction Canada Project Location: Dwyer Hill Training Centre, Richmond, ON Datum: Geodetic BH Location: See Borehole Location Plan N E (m) ELEV DEPTH SOIL PROFILE DESCRIPTION ASPHALT mm CRUSHED SAND and GRAVEL, some silt, trace clay, brown, moist, compact (Road Base) GRAVELLY SILTY SAND, brown, moist, loose to compact (Fill) STRATA PLOT NUMBER 1 SAMPLES TYPE SS "N" BLOWS 0.3 m 25 GROUND WATER CONDITIONS ELEVATION 110 DRILLING DATA Rig Type:Truckmount CME 75 Method: Hollow Stem Auger Borehole Diameter: 203 mm Core Diameter: - DYNAMIC CONE PENETRATION RESISTANCE PLOT NATURAL PLASTIC MOISTURE LIMIT CONTENT w P w w L SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE WATER CONTENT (%) Project No.: Date Started: 1/13/2016 Supervisor: D. Robertson Reviewer: B. Goddard LIQUID LIMIT POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (KN/m 3 ) REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL (19) 2 SS (33) 3 SS GRAVELLY SILTY SAND, grey, moist, compact to very dense (Glacial Till) 4 SS SS SS (29) WSP SOIL LOG - OTTAWA GINT DCC DWYER HILL.GPJ SPL.GDT 1/25/ END OF BOREHOLE 1) Auger refusal was encountered at 4.72 m below the existing ground surface. 2) Borehole dry upon completion of augering. 7 SS >50 GROUNDWATER ELEVATIONS GRAPH NOTES 3, 3 : Numbers refer to Sensitivity =3% Strain at Failure Sheet No. 1 of 1 Shallow/ Single Installation Deep/Dual Installation

26 LOG OF BOREHOLE 16-2 Project: Specialized Equipment Accommodation, DHTC Client: Defense Construction Canada Project Location: Dwyer Hill Training Centre, Richmond, ON Datum: Geodetic BH Location: See Borehole Location Plan N E (m) ELEV DEPTH SOIL PROFILE DESCRIPTION ASPHALT - 60 mm SILTY SAND and CRUSHED GRAVEL, brown, moist, compact (Road Base) GRAVELLY SILTY SAND, trace organics, brown, moist, compact (Fill) STRATA PLOT NUMBER 1 SAMPLES TYPE SS "N" BLOWS 0.3 m 27 GROUND WATER CONDITIONS ELEVATION DRILLING DATA Rig Type:Truckmount CME 75 Method: Hollow Stem Auger Borehole Diameter: 203 mm Core Diameter: 63 mm DYNAMIC CONE PENETRATION RESISTANCE PLOT NATURAL PLASTIC MOISTURE LIMIT CONTENT w P w w L SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE WATER CONTENT (%) Bentonite Seal Project No.: Date Started: 1/14/2016 Supervisor: D. Robertson Reviewer: B. Goddard LIQUID LIMIT POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (KN/m 3 ) REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL (21) SS SILTY SAND, some gravel, trace clay, grey, loose to very dense (Glacial Till) 3 SS 9 Cuttings (49) DOLOMITE, fresh, thin to medium bedded, light grey, some calcite veins and vugs Core: RC-5: 2.79 m to 4.37 m - TCR: 97% - SCR: 94% - RQD: 84% 4 5 SS CORE 50 /50 mm W. L m Jan 22, 2016 Bentonite 108 Seal UCS = 94.0 MPa Unit Weight = 26.8 kn/m3 Sand 107 WSP SOIL LOG - OTTAWA GINT DCC DWYER HILL.GPJ SPL.GDT 1/25/ DOLOMITIC LIMESTONE, slightly weathered to fresh, thinly bedded, closely jointed, dark grey Core: RC-6: 4.37 m to 5.84 m - TCR: 100% - SCR: 93% - RQD: 73% END OF BOREHOLE 1) Auger refusal was encountered at 2.79 m below the existing ground surface. Switched to NQ coring. 2) Borehole dry upon completion of augering. 3) 31 mm standpipe piezometer installed at 5.89 m below the existing ground surface. 4) Date Groundwater Depth /23/ m 6 CORE 106 Screen and sand UCS = 87.0 MPa Unit Weight = 27.3 kn/m3 GROUNDWATER ELEVATIONS GRAPH NOTES 3, 3 : Numbers refer to Sensitivity =3% Strain at Failure Sheet No. 1 of 1 Shallow/ Single Installation Deep/Dual Installation

27 LOG OF BOREHOLE 16-3 Project: Specialized Equipment Accommodation, DHTC Client: Defense Construction Canada Project Location: Dwyer Hill Training Centre, Richmond, ON Datum: Geodetic BH Location: See Borehole Location Plan N E (m) ELEV DEPTH SOIL PROFILE DESCRIPTION SILTY SAND and CRUSHED GRAVEL, brown, moist, very dense (Road Base) SILTY SAND and GRAVEL, brown, moist, compact (Fill) STRATA PLOT NUMBER 1 SAMPLES TYPE SS "N" BLOWS 0.3 m >50 GROUND WATER CONDITIONS ELEVATION 111 DRILLING DATA Rig Type:Truckmount CME 75 Method: Hollow Stem Auger Borehole Diameter: 203 mm Core Diameter: - DYNAMIC CONE PENETRATION RESISTANCE PLOT NATURAL PLASTIC MOISTURE LIMIT CONTENT w P w w L SHEAR STRENGTH (kpa) FIELD VANE UNCONFINED & Sensitivity QUICK TRIAXIAL LAB VANE WATER CONTENT (%) Project No.: Date Started: 1/13/2016 Supervisor: D. Robertson Reviewer: B. Goddard LIQUID LIMIT POCKET PEN. (Cu) (kpa) NATURAL UNIT WT (KN/m 3 ) REMARKS AND GRAIN SIZE DISTRIBUTION (%) GR SA SI CL 2 SS (22) SILTY SAND, some gravel, brown, moist, compact (Glacial Till) S-3: trace organics 3 SS SS (42) END OF BOREHOLE 1) Auger refusal was encountered at 3.02 m below the existing ground surface. 2) Borehole dry upon completion of augering. WSP SOIL LOG - OTTAWA GINT DCC DWYER HILL.GPJ SPL.GDT 1/25/16 GROUNDWATER ELEVATIONS GRAPH NOTES 3, 3 : Numbers refer to Sensitivity =3% Strain at Failure Sheet No. 1 of 1 Shallow/ Single Installation Deep/Dual Installation

28 RUN RC-5: 2.79 m m Borehole BH16-2 Client: Defence Construction Canada Project#: DWG #: B-1 Drawn: BDG Approved: CH Date: January 2016 Scale: N. T. S. Size: Letter Rev: 0 Title: Project: Core Photograph Geotechnical Investigation Dwyer Hill Training Centre, Richmond, ON

29 RUN RC-6 : 4.37 m m Borehole BH16-2 Client: Defence Construction Canada Title: Core Photograph Project#: DWG #: B-2 Geotechnical Investigation Project: Drawn: BDG Approved: CH Dwyer Hill Training Centre, Richmond, ON Date: January 2016 Scale: N. T. S. Size: Letter Rev: 0

30 CORROSIVITY TESTING RESULTS

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33 Appendix D EXPLANATION OF TERMS USED IN REPORT

34 EXPLANATION OF TERMS USED IN REPORT N-VALUE: THE STANDARD PENETRATION TEST (SPT) N-VALUE IS THE NUMBER OF BLOWS REQUIRED TO CAUSE A STANDARD 51mm O.D SPLIT BARREL SAMPLER TO PENETRATE 0.3m INTO UNDISTURBED GROUND IN A BOREHOLE WHEN DRIVEN BY A HAMMER WITH A MASS OF 63.5 kg, FALLING FREELY A DISTANCE OF 0.76m. FOR PENETRATIONS OF LESS THAN 0.3m N-VALUES ARE INDICATED AS THE NUMBER OF BLOWS FOR THE PENETRATION ACHIEVED. AVERAGE N-VALUE IS DENOTED THUS N. DYNAMIC CONE PENETRATION TEST: CONTINUOUS PENETRATION OF A CONICAL STEEL POINT (51mm O.D. 60 CONE ANGLE) DRIVEN BY 475J IMPACT ENERGY ON A SIZE DRILL RODS. THE RESISTANCE TO CONE PENETRATION IS MEASURED AS THE NUMBER OF BLOWS FOR EACH 0.3m ADVANCE OF THE CONICAL POINT INTO THE UNDISTURBED GROUND. SOILS ARE DESCRIBED BY THEIR COMPOSITION AND CONSISTENCY OR DENSENESS. CONSISTENCY: COHESIVE SOILS ARE DESCRIBED ON THE BASIS OF THEIR UNDRAINED SHEAR STRENGTH (c u ) AS FOLLOWS: C u (kpa) >200 VERY SOFT SOFT FIRM STIFF VERY STIFF HARD DENSENESS: COHESIONLESS SOILS ARE DESCRIBED ON THE BASIS OF DENSENESS AS INDICATED BY SPT N VALUES AS FOLLOWS: N (BLOWS/0.3m) >50 VERY LOOSE LOOSE COMPACT DENSE VERY DENSE ROCKS ARE DESCRIBED BY THEIR COMPOSION AND STRUCUTRAL FEATURES AND/OR STRENGTH. RECOVERY: SUM OF ALL RECOVERED ROCK CORE PIECES FROM A CORING RUN EXPRESSED AS A PERCENT OF THE TOTAL LENGTH OF THE CORING RUN. MODIFIED RECOVERY: SUM OF THOSE INTACT CORE PIECES, 100mm+ IN LENGTH EXPRESSED AS A PERCENT OF THE LENGTH OF THE CORING RUN. THE ROCK QUALITY DESIGNATION (RQD), FOR MODIFIED RECOVERY IS: JOINT AND BEDDING: RQD (%) VERY POOR POOR FAIR GOOD EXCELLENT SPACING 50mm mm 0.3m 1m 1m 3m >3m JOINTING VERY CLOSE CLOSE MOD. CLOSE WIDE VERY WIDE BEDDING VERY THIN THIN MEDIUM THICK VERY THICK ABBREVIATIONS AND SYMBOLS FIELD SAMPLING MECHANICALL PROPERTIES OF SOIL SS SPLIT SPOON TP THINWALL PISTON m v kpa -1 COEFFICIENT OF VOLUME CHANGE WS WASH SAMPLE OS OSTERBERG SAMPLE c c 1 COMPRESSION INDEX ST SLOTTED TUBE SAMPLE RC ROCK CORE c s 1 SWELLING INDEX BS BLOCK SAMPLE PH TW ADVANCED HYDRAULICALLY c a 1 RATE OF SECONDARY CONSOLIDATION CS CHUNK SAMPLE PM TW ADVANCED MANUALLY c v m 2 /s COEFFICIENT OF CONSOLIDATION TW THINWALL OPEN FS FOIL SAMPLE H m DRAINAGE PATH T v 1 TIME FACTOR STRESS AND STRAIN U % DEGREE OF CONSOLIDATION u w kpa PORE WATER PRESSURE vo kpa EFFECTIVE OVERBURDEN PRESSURE r u 1 PORE PRESSURE RATIO p kpa PRECONSOLIDATION PRESSURE kpa TOTAL NORMAL STRESS f kpa SHEAR STRENGTH kpa EFFECTIVE NORMAL STRESS c kpa EFFECTIVE COHESION INTERCEPT kpa SHEAR STRESS Ф - o EFFECTIVE ANGLE OF INTERNAL FRICTION l, 2, 3 kpa PRINCIPAL STRESSES c u kpa APPARENT COHESION INTERCEPT % LINEAR STRAIN Ф u - o APPARENT ANGLE OF INTERNAL FRICTION 1, 2, 3 % PRINCIPAL STRAINS R kpa RESIDUAL SHEAR STRENGTH E kpa MODULUS OF LINEAR DEFORMATION r kpa REMOULDED SHEAR STRENGTH G kpa MODULUS OF SHEAR DEFORMATION S t 1 SENSITIVITY = c u / r 1 COEFFICIENT OF FRICTION PHYSICAL PROPERTIES OF SOIL P s kg/m 3 DENSITY OF SOLID PARTICLES e 1,% VOID RATIO e min 1,% VOID RATIO IN DENSEST STATE s kn/m 3 UNIT WEIGHT OF SOLID PARTICLES n 1,% POROSITY I D 1 DENSITY INDEX = e,max e e max - e min P w kg/m 3 DENSITY OF WATER w 1,% WATER CONTENT D mm GRAIN DIAMETER w kn/m 3 UNIT WEIGHT OF WATER s r % DEGREE OF SATURATION D n mm N PERCENT DIAMETER P kg/m 3 DENSITY OF SOIL w L % LIQUID LIMIT C u 1 UNIFORMITY COEFFICIENT kn/m 3 UNIT WEIGHT OF SOIL w P % PLASTIC LIMIT h m HYDRAULIC HEAD OR POTENTIAL P d kg/m 3 DENSITY OF DRY SOIL w s % SHRINKAGE LIMIT q m 3 /s RATE OF DISCHARGE d kn/m 3 UNIT WEIGHT OF DRY SOIL I P % PLASTICITY INDEX = (W L W L ) v m/s DISCHARGE VELOCITY P sat kg/m 3 DENSITY OF SATURATED SOIL I L 1 LIQUIDITY INDEX = (W W P )/ l P i 1 HYDAULIC GRADIENT sat kn/m 3 UNIT WEIGHT OF SATURATED SOIL I C 1 CONSISTENCY INDEX = (W L W) / 1 P k m/s HYDRAULIC CONDUCTIVITY P kg/m 3 DENSITY OF SUBMERED SOIL e,max 1,% VOID RATIO IN LOOSEST STATE j kn/m 3 SEEPAGE FORCE kn/m 3 UNIT WEIGHT OF SUBMERGED SOIL