Ottawa, June 5, Ms. Monica Dashwood Director of Development Viva Retirement Communities 3845 Bathurst Street, Suite 206 Toronto, Ontario M3H 3N2

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1 REPORT: T A2 VIVA RETIREMENT COMMUNITIES Geotechnical Investigation Report Five-Story Retirement Home Strandherd Drive and Tartan Drive Ottawa, Ontario June 5, 2013

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3 Ottawa, June 5, 2013 Ms. Monica Dashwood Director of Development Viva Retirement Communities 3845 Bathurst Street, Suite 206 Toronto, Ontario M3H 3N2 Subject: Geotechnical Investigation Report (T A1) Five-Story Retirement Home Strandherd Drive and Tartan Drive Ottawa, Ontario Dear Ms. Dashwood: As requested, Inspec-Sol Inc. (Inspec-Sol) has completed the Geotechnical Investigation for the above-mentioned project. We herein offer the following comments and recommendations for the proposed development. The Inspec-Sol team is committed to exceeding the expectations of its clients. Do not hesitate to contact us for any further information. Best regards. INSPEC-SOL INC. Joseph B. Bennett, P.Eng Vice President Enclosure JBB/nc

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5 VIVA RETIREMENT COMMUNITIES Geotechnical Investigation Five-Story Retirement Home Strandherd Drive and Tartan Drive Ottawa, Ontario Date : June 5, 2013 Our Ref. : T A2

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7 VIVA RETIREMENT COMMUNITIES 3845 Bathurst Street, Suite 206 Toronto, Ontario M3H 3N2 Geotechnical Investigation Five-Story Retirement Home Strandherd Drive and Tartan Drive Ottawa, Ontario Ref. : T A2 June 5, 2013 Prepared by : Shane Dunstan, B.A.Sc., E.I.T. Approved by : Joseph B. Bennett, P.Eng Distribution : Client Ms. Monica Dashwood (Copy by monica@vivalife.ca) & Mail (6)

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9 Respect for the environment and the preservation of our natural resources are priorities for Inspec-Sol Inc. With this in mind, we print our documents double-sided on 50 % recycled paper.

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11 TABLE OF CONTENTS 1.0 INTRODUCTION SITE AND PROJECT DESCRIPTION FIELDWORK INITIAL BOREHOLES (DECEMBER 2010) ADDITIONAL BOREHOLES (CURRENT MANDATE) GEOPHYSICAL TESTING LABORATORY TESTING SUBSOIL CONDITIONS SURFICIAL COVERINGS CLAYEY SILT NATIVE SILT AND CLAY SILTY AND GRAVELLY SAND BEDROCK GROUNDWATER DISCUSSION AND RECOMMENDATIONS PROJECT DESCRIPTION AND GENERAL CONSIDERATIONS SITE PREPARATION EXCAVATION AND DEWATERING FOUNDATIONS Piled Foundations Settlement Resistance to Foundation Uplift Frost Protection Seismic Site Classification LATERAL EARTH PRESSURES Static Conditions Dynamic Conditions PERMANENT DRAINAGE Perimeter Drainage and Foundation Wall Waterproofing... 17

12 TABLE OF CONTENTS (CONT D) Under-Floor Waterproofing BUILDING BACKFILL Engineered Fill Exterior Foundation Wall Backfill FLOOR SLABS UNDERGROUND SERVICES Bedding and Cover Service Trench Backfill PAVEMENT SECTIONS CONSTRUCTION FIELD REVIEW REPORT CONDITIONS AND LIMITATIONS Tables MASW Line Geometry Page 04 Refusal Depths in Boreholes Page 07 Groundwater Observations Page 08 Lateral Earth Pressure Page 16 Recommend Pavement Structure Page 23 Drawings Site Location Plan T A2-1 Borehole/Rock Probe Location Plan T A2-2 MASW Line Layout T A2-3 Perimeter Drainage Alternative T A2-4 Enclosures Borehole Logs / Grain Size Analysis BH1 to BH8 Appendix A Appendix B Seismic Site Classification Notes on Borehole and Test Pit Logs

13 1.0 INTRODUCTION Inspec-Sol Inc. (Inspec-Sol) was retained by Viva Retirement Communities (Client) to undertake a Geotechnical Investigation for the proposed five (5) storey retirement residence at 275 Tartan Drive in Ottawa, Ontario (Site). The scope of work was outlined in the Proposal (Ref No: FP3616, dated September 21, 2011), and authorization to proceed with this study was provided by Ms. Monica Dashwood representing the Client on October 3, A draft report was submitted in December 2011 and following recent input from designers the report is now being finalized in June The purpose of this investigation was to provide a Final Geotechnical Investigation report to supplement the previous report entitled Geotechnical Investigation Preliminary Findings (Inspec-Sol Ref No.: T A1, dated December 21, 2010). The previous scope of work had boreholes spread over a larger property than the current investigation. The current investigation is intended to serve as the final report for the proposed development in the northhalf of the original property (see Dwg No.: T A2-2). This report has been prepared with the understanding that the design will be carried out in accordance with all applicable codes and standards. Any changes to the project described herein will require that Inspec-Sol be retained to assess the impact of the changes on the recommendations provided. The scope of work for Inspec-Sol consisted of the following activities: Underground Utility Locates: Boreholes: Advancement of two (2) boreholes to practical refusal or to a maximum depth of 30 m; Lab Testing: A maximum of twenty (20) moisture contents, six (6) grain sizes, six (6) Atterberg limits, and two (2) consolidation tests by the odometer method; Geophysical Testing: MASW survey to assist in the assignment of a site classification for seismic site response according to Table of the Ontario Building Code (OBC-2006); and Reporting: Prepare a Geotechnical Report, which summarizes the findings of the current and previous fieldwork programs and presents recommendations for the design and construction of the structure. Geotechnical Investigation Report 1 Ref. No.. : T A2 June 5, 2013

14 2.0 SITE AND PROJECT DESCRIPTION The client s property is bounded by Tartan Drive to the north and west, due to a turn in the road and Strandherd Drive to the south. There is an existing school to the east. The current investigation is focused on the north half, and referred to as the Site herein; the location of the Site within the City of Ottawa is shown in the Site Location Map, attached as Dwg No.: T A2-1, at the end of this report. The Site is currently undeveloped and has no existing structures and Inspec-Sol is of the understanding that the proposed development will be the first development for this Site. There is a line of mature trees which run along the approximate midpoint of the Site. The existing ground surface at this Site is approximately 0.6 m lower in elevation than the adjacent roadways to the north, west, and south. It is at a similar elevation to that of the existing school yard to the east of the Site with general grades ranging between, approximately 92.5 to 93.5m. It is our understanding that the building will be five (5) stories in height with one basement level and the ground floor set at geodetic elevation 93.0m 3.0 FIELDWORK The Geotechnical Investigation Preliminary Findings (Inspec-Sol Ref No.: T A1, dated December 21, 2010) included borehole drilling at six (6) locations. The current program included two (2) deep boreholes. We also completed a Geophysical survey, performed using a multi-channel analysis of surface waves (MASW), as part of the current mandate. An outline of the fieldwork done to date is provided in the following sections. 3.1 Initial Boreholes (December 2010) The fieldwork component of the initial Geotechnical Investigation Preliminary Findings consisted of the advancement of a total of six (6) boreholes. Boreholes BH-1 to BH-6, were advanced to varying depths into the native clay and silt using standard split-spoon samplers. A dynamic cone penetration test (DCPT) was then carried out and advanced to practical refusal. Boreholes BH-1 and BH-6 were outfitted with standpipes. The location of the boreholes is 2 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

15 shown in the Borehole Location Plan attached as Dwg No.: T A2-2, at the end of this report. This initial borehole program was undertaken on December 18 and 20, 2010 using a small track-mounted geo-probe, under the supervision of Inspec-Sol field staff. Boreholes were advanced using 75 mm direct-push casings. Standard Penetration Tests (SPT) were performed at regular intervals using a 50 mm diameter split-spoon sampler. 3.2 Additional Boreholes (Current Mandate) The drilling component of this current mandate consisted of the advancement of two (2) additional. Boreholes BH-7 and BH-8 were advanced to practical refusal to auger advancement. The boreholes were further advanced using casing and coring to obtain a confirmatory rock core in each. Boreholes were terminated at depths of 22.5 m and 23.9 m, respectively. The location of the boreholes is shown in the Borehole Location Plan attached as Dwg No.: T A2-2, at the end of this report. The additional borehole program was undertaken on October 24 and 25, 2011 with a specialized track-mounted drill rig adapted for soil sampling, under the supervision of Inspec- Sol field staff. Boreholes were advanced into the overburden using hollow-stem continuousflight auger equipment. Standard Penetration Tests (SPT) were performed at regular intervals using a 50 mm diameter split-spoon sampler and a 63.5 kg hammer free falling from a distance of 760 mm, to collect soil samples. The number of drops required to drive the sampler 0.3 m is recorded on the borehole logs as N value. Where applicable, the undrained shear strength of the soil was estimated using a field vane. Boreholes were backfilled upon completion with a bentonite hole plug. The elevations of the boreholes were determined by Inspec-Sol interpreting the elevations from a site plan supplied by the client s civil consultant. The elevations are geodetic. 3.3 Geophysical Testing The geophysical testing component was carried out on November 4, The purpose of this testing was to determine the average shear wave velocity of the soil to a depth of 30 m below the anticipated underside of footings or pile caps. The test was carried out using a 24 channel seismograph (Geometrics Geode 24 consol #3389) consisting of twenty four (24), 4.5 Hz geophones, connected to a 24 take-out cable Geotechnical Investigation Report 3 Ref. No.. : T A2 June 5, 2013

16 with 5 m spacing. The data was collected using Geometrics single geode OS controller version and a field laptop. The geophone arrays were laid down using multi-station approach, where data along each investigation line (Lines 1 and 2) was collected using multiple geophone spacing geometries. For example the first set of data was collected using geophones mounted every 4.0 m (long array), a second set of data was collected with a geophone spacing of 2.0 m (medium array), and a third set of data was collected with a geophone spacing of 1.0 m (short array). In general the longer array length provides information over a greater depth and shorter arrays provide more detail information at shallower depths. It is noted that in all the geometries the midpoint of the geophone arrays was kept the same so that the collected data can be combined. Table 1 below shows the details of the geometry along each investigated line. The approximate locations of investigation lines are shown in the MASW Line Layout attached as Dwg. No.: T A2-3, at the end of this report TABLE 1: MASW Line Geometry Line No. Long Array Medium Array Short Array Spacing (m) Hammer Offset (m) Spacing (m) Hammer Offset (m) Spacing (m) Hammer Offset (m) L , 40, , 20, , 10, 5 L , 40, , 20, , 10, 5 A 200 lb drop weight hitting a steel base plate was used for active data acquisition. For each active survey, the ground vibration was recorded for 4 seconds at a sampling rate of one sample per 0.25 m. The results of the geophysical testing program can be found in Seismic Site Classification attached as Appendix: A at the end of this report. 4 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

17 4.0 LABORATORY TESTING The laboratory testing component of this current mandate consisted of twenty two (22) moisture contents, and a total of six (6) Atterberg limits determinations. Six (6) grain size analyses were performed using hydrometers. Two (2) consolidation tests were performed using the odometer method. The results of selected laboratory testing are used in the soil descriptions below, and are also shown on the Borehole Logs attached as Enclosure Nos: 1 to 8, at the end of this report. 5.0 SUBSOIL CONDITIONS The soils at the eight (8) borehole locations were found to generally consist of a surficial covering of topsoil followed by a shallow depth of clayey silt with traces of sand. In all cases the surficial soils were found to be underlain by a native silt and clay. A gravelly sand and silt layer was found below 15 m and overlying the limestone bedrock, and was of varying thicknesses. General descriptions of the observed subsurface conditions are summarized below, with detailed descriptions at the borehole locations provided in the Borehole Logs attached as Enclosure Nos: 1 to 8, at the end of this report. Notes on Borehole and Test Pit Logs are provided in Appendix B. 5.1 Surficial Coverings In all borehole locations, an organic topsoil/root mass was found to cover the surface. The topsoil was found to be underlain by clayey silt and then silt and clay. 5.2 Clayey Silt A clayey silt layer was found in some boreholes to underlay the cover. It was stiff to very stiff in consistency and mottled brown in colour. Trace oxidation was observed, and the samples were recovered in a damp condition. This was approximately 1 m thick, was found in BH-7 and BH-8, and may be present in other locations. The topsoil descriptions within this report and in the borehole logs should not be used for quality assessments or quantity take-offs. Geotechnical Investigation Report 5 Ref. No.. : T A2 June 5, 2013

18 5.3 Native Silt and Clay A native Silt and Clay was found in all borehole locations. The upper desiccated crust section of this Silt and Clay was found to be stiff in consistency, light brown to grey in colour. It was recovered in a moist condition. The desiccated crust was inferred to extend to a depth near approximately ±3 m. This would correspond to a geodetic elevation of approximately 90±0.5. Below this approximate depth the Silt and Clay was found to be only firm in consistency and grey in colour. The samples were recovered in a wet condition. Atterberg limits testing on selected samples of this Silt and Clay suggest that it would be an inorganic soil of high plasticity. In most cases, the moisture content was found to be at or above the liquid limit. 5.4 Silty and Gravelly Sand In boreholes BH-7, and BH-8, samples of deeper silty gravelly sand were recovered. This soil was described as a gravelly sand and silt in the upper zones of this deposit and a silty gravelly sand in the lower zone of this deposit. Generally, unsorted deposits such as this, which exhibit the full spectrum of particle sizes and directly overly bedrock, are commonly referred to as glacial till deposits. Within the test locations, the till was found to be loose to compact in the upper zones, and becoming dense to very dense with depth. It was light grey in colour and was recovered in a wet condition. It is expected that this till contains cobbles and boulders. In both test locations, rock coring was used to advance through boulders that were up to approximately 0.3 m in diameter. This till was found at approximate depths of 15.6 m and 15.4 m in boreholes BH-7 and BH-8, respectively. This would correspond to an approximate elevation near 77 m. In boreholes BH-1, BH-3, BH-4, BH-5, and BH-6, the depth of the till was inferred based on the observations during the DCPT. In these locations, the top of till is inferred to be at depths on approximately 13.4 m, 13.4 m, 17.8 m, 12.0 m, and 16.4 m, respectively. 5.5 Bedrock Confirmatory rock cores were recovered in boreholes BH-7 and BH-8. The bedrock was found to consist of a crystalline limestone. It was medium grey in colour, and was cut with stylolites and shaley seams. Numerous sub-horizontal planar joints were observed within the 6 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

19 cored depth. The top of bedrock was observed at approximate elevations of 71.7 m and 70.2 m in boreholes BH-7 and BH-8 respectively. The following table, Table 2, shows the refusal depths of the DCPT tests in each of the eight (8) boreholes. However caution should be used in inferring the bedrock depth from this data, as cobbles and boulders were observed within the till. Some of these refusals may represent refusal on a boulder and not bedrock. TABLE 2: Refusal Depth and/or Depth to Bedrock Borehole No. Grade Refusal Observations Elevation Depth Elevation Comments BH Possible Boulder Refusal BH Possible Boulder Refusal BH BH BH Possible Boulder Refusal BH BH Confirmed Bedrock by Coring BH Confirmed Bedrock by Coring There is the risk of encountering cobbles and boulders especially within the till. Contractors bidding on the pile driving should be aware of and account for this risk. Based on publicly available geological mapping, this area of the City is reported to be underlain by an interbedded limestone and dolomite of the Gull River Formation. The bedrock is reported at depths ranging from approximately 15 to 25 m, which is consistent with the findings of this investigation. 6.0 GROUNDWATER Two (2) standpipes were installed as part of the December 2010 initial boreholes. The following table, Table 3, shows the water levels observed in the standpipes. Groundwater Geotechnical Investigation Report 7 Ref. No.. : T A2 June 5, 2013

20 levels at the time of the investigation were inferred based on the sample appearance, which was estimated to be approximately 3.0 m to approximately 4.5 m below the existing ground surface. TABLE 3: Groundwater Observations Borehole No. Grade Depth to Elevation of Elevation Water (m) water (m) Date of Observation MW/BH December 21, 2010 MW/BH October 25, 2011 MW/BH December 21, 2010 MW/BH October 25, 2011 Based on the above, observations, and inference with the moisture contents shown on the borehole logs, the groundwater table is expected to be near an elevation of 91 m ± 1.0 m. However, it should be noted that groundwater levels are subject to seasonal fluctuations as well as precipitation and snowmelt events. 7.0 DISCUSSION and RECOMMENDATIONS 7.1 Project Description and General Considerations The recommendations contained within this report are based on Inspec-Sol s understanding of the proposed development, which is based on the drawing Master Plan, Dwg No.: A101 (Arsenault Architect Inc., Ref No.: , dated September 23, 2011), which was received from the Client. Our understanding of the project is as follows: The proposed building consists of a five (5) storey structure; The proposed building consists of two components: the east and the west; The eastern portion of the structure has one (1) full level of basement. A portion of this is to be used as underground parking, and the remainder is to be finished usable space; and The western portion of this structure has a slab on grade and no (0) basement level. Based on the above project description, it is assumed that in the areas where there is a basement level, the underside of the footings or grade beams are expected to be near an approximate depth of 3 to 4 m below the existing surface grade. Where the building is not 8 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

21 underlain by a basement, it is assumed that the footings or grade beams will be at an approximate depth of 1.5 m below the existing surface grade, to account for frost protection. If any of these assumptions are incorrect or these facts change through the design or construction phases, Inspec-Sol must be notified and retained to assess the impact on our recommendations. Based on the subsurface conditions encountered in the boreholes, and assuming them to be representative of the subsurface conditions across the Site, the following recommendations are provided. The most significant geotechnical considerations for design of the proposed structure are: Limitation of Grade Raises: Significant grade raises on this Site would result in consolidation settlement of the underlying clays. It is recommended that grade raises on this Site be limited to a maximum of 0.6 m. If higher grade raises are necessary, then a settlement analysis will need to be performed to assess the impact. Furthermore, the use of light weight would likely be necessary; Groundwater: Groundwater elevation is reported near 91 m ± 1.0 m which implies excavation for the basement will be near the water table. Groundwater and surface water infiltration into excavations need to be adequately controlled in order to maintain adequate working conditions; and Permanent Drainage: For buildings such as this which have basements below the water table, it is necessary that permanent drainage be provided using perimeter drains, and underfloor drains. It is also recommended that the design incorporate a composite drainage blanket on the exterior walls, which is underlain by a waterproofing membrane. It is recommended that a heavy duty vapour barrier be incorporated under the basement slab for the parking areas. 7.2 Site Preparation Site preparation within the footprint of the building and the pavement structure will require the stripping of surficial topsoil, root-mat, and any fill soils or other deleterious materials to expose a suitable native subgrade. Geotechnical Investigation Report 9 Ref. No.. : T A2 June 5, 2013

22 Piling foundations are being recommended and based upon the basement/non-basement areas of the building, an option may be to drive the piles and then excavate. Granular piling pads may be required to provide a stable base for the cranes and contractors equipment. The time of year that construction is carried out will also play a role in the decision by the contractor. In pavement areas, the exposed subgrade should be assessed by geotechnical personnel, during construction, by means of proof-rolling or probing, to identify soft spots or local anomalies prior to placing pavement structures. Any areas which exhibit substantial deflection should be sub-excavated and replaced with a suitable fill as per the directions of the Geotechnical Engineer and Section 7.10 of this report. The Site should also be graded in the early stages of construction to encourage surface run-off away from excavations. In wet seasons, conventional types of ditching and pumping system may be required by Contractors in order to collect any surface run-off. Inspec-Sol did not complete a hydrogeological assessment of this site as part of the scope of work. 7.3 Excavation and Dewatering All excavations should be completed and maintained in accordance with the current Occupational Health and Safety Act (OHSA) Regulations for Construction. The following recommendations for excavations should be considered to be a supplement to, and not a replacement of the OHSA requirements. Based on the results of the investigation, the silt and clay within excavation to an approximate depth of 3.0 m or lower would be considered as Type 3 Soils, as defined by the OHSA Regulations for Construction. Shallow excavation may be considered as Type 2 conditions. Based on our understanding of the proposed development, it is expected that the deepest excavations on this Site will be associated with the construction of the underground parking garage, which is anticipated to extend down to an elevation of approximately 90 m. Based on the drawing Master Plan, Dwg No.: A101, provided by the Client, it is understood that there is a 4.5 m setback from the property line on the north and east sides of the Site. Based on an anticipated excavation depth of approximately 3.5 m, there should be adequate room 10 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

23 to provide the necessary 1H:1V side slope as required by OHSA for a Type 3 Soil. Therefore shoring is not expected to be necessary for the short term construction period. Surface water and groundwater seepage is expected in all excavations. Water quantities will depend on seasonal conditions, depth of excavations, and the duration that excavations are left open. However, due to the lower permeable soils expected to 3 to 4 m, conventional construction dewatering techniques should be adequate during construction. Construction methods should prevent or minimize disturbing the subgrade soils, such as pumping from sumps and or ditches. Permits To Take Water (PTTW) are required under Ontario Regulations when there is greater than 50,000L/day being pumped. Contractors should ensure this is not exceeded during construction or obtain a PTTW. 7.4 Foundations The Ontario Building Code (OBC-2006) requires buildings to be designed using the limit states design values of Serviceability Limit States (SLS) and Ultimate Limit States (ULS). Based on the soil settlement parameters that were determined using the consolidation tests on samples BH-7, ST-5; and BH-8, ST-7; Inspec-Sol performed a preliminary settlement analysis to assess the feasibility of using traditional spread footings founded at different elevations within the native silt and clay. Pad footing sizes of 2.0 m by 2.0 m were used along with strip footings 1.5 m wide. A design bearing pressure of 100 kpa was used and the four (4) scenarios for analyses were performed: 0.6 m grade raise, 2.0 m by 2.0 m pad footings, founded at 94.5 m, and a design bearing pressure of 100 kpa under SLS conditions; 0.6 m grade raise, 1.5 m wide strip footings, founded at 94.5 m, and a design bearing pressure of 100 kpa under SLS conditions; 0.6 m grade raise, 2.0 m by 2.0 m pad footings, founded at 96.3 m, and a design bearing pressure of 100 kpa under SLS conditions; and 0.6 m grade raise, 1.5 m wide strip footings, founded at 96.3 m, and a design bearing pressure of 100 kpa under SLS conditions. The above preliminary settlement analyses resulted in total settlements of greater than 25 mm, which is the typical total settlement limit for design. Based on these results and the fact that footing size and pressure may actually be larger than our scenarios, it is recommended Geotechnical Investigation Report 11 Ref. No.. : T A2 June 5, 2013

24 that this building be designed using a deep foundation system consisting of piles driven to refusal Piled Foundations It is recommended that H Piles or concrete filled steel pipe piles, driven to refusal on the bedrock or provide the required foundation support for this building. Once the column loads are known, piling contractors will provide the most economical piles depending on availability. The approximate factored Geotechnical resistance at ULS conditions of some common pile sizes are as follows. Typically for such conditions the geotechnical resistance is similar to the structural capacity of the piles. H Piles 8 x kn 10 x kn Pipe Piles 9 5/8 x kn 7 x kn The values provided above are approximate because the materials used by piling contractors to determine pile capacity vary somewhat, however, the values provided are considered to be a reasonable guideline for determining the number of piles required. Inspec-Sol should be retained to review the pile shop drawings at the outset of the project. There is the risk of encountering cobbles and boulders especially in the soils below depth of approximately 15 m. Contractors bidding on the pile driving should be aware of and account for this risk. It is recommended that Pile Driving Analysis (PDA) be performed on a minimum of 5% of the piles. It should be completed at two stages during construction: after the start of pile driving to confirm the refusal criteria established for this project, and then after 50% of the piling is completed. Re-striking of all piles is recommended for this Site, to ensure that uplift of adjacent piles is avoided. Subject to satisfactory results, a second re-striking of piles is envisaged to be carried out only on a random basis (i.e., about 20 % of the piles) unless their capacity is suspect, or unless previously driven piles have moved during the placement of adjacent piles. 12 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

25 It is recommended that Inspec-Sol be retained at the outset of construction to complete a review for compliance with our recommendations and during construction to verify suitability of foundation subgrades Settlement For buildings which are founded on piles driven to refusal, settlement is expected to be nil at the pile tip. However, it is necessary that grade raises not exceed the 0.6 m limit as this could result in consolidation settlement of the basement slab-on grade Resistance to Foundation Uplift It is anticipated that resistance to foundation uplift, if necessary for seismic issues would be provided by means of dead weight grouted rock anchors. Grouted rock anchors may be designed based on a frictional stress between grout and the granitic bedrock. Based upon typical published values and conservative approach, we recommend that a conservative allowable working stress value of 690 kpa be utilized to calculate the length of the required bond zone. The bond zone must be entirely within sound bedrock which is below the weathered zone. An allowance for a weathered rock zone of 1.0 m in each hole should be incorporated. Designing in accordance with the Limit State Design (LSD) method, designers may take the approach that working stress value is approximately equivalent to the SLS value. The ULS and SLS must be based upon performance and structural criteria. However, based upon typical published values, the ULS values may be approximately 1.5 MPa to more than 2.0 MPa. As per the Canadian Foundation Engineering Manual (CFEM-2006), a geotechnical resistance factor of Ф = 0.3 should be applied to this empirical ULS. Higher stress values may be available; however as stated, performance load testing in the field will be required to prove the capacities. If performance testing is carried out at the outset of the project, then a resistance factor of Ф = 0.4 can be applied as per CFEM In order to mobilize the shear stress in the rock, the load at the top of the anchor zone must be properly transferred through the anchor zone to prevent progressive grout fail and ensure proper performance. Therefore, a free length is required through the overburden and the weathered rock zone. The mass of rock mobilized by a rock anchor may be assumed to be based upon a 60 o cone drawn up from a point located at the lower one-third point of the anchor shaft bond zone and Geotechnical Investigation Report 13 Ref. No.. : T A2 June 5, 2013

26 spaced such that the theoretical cones do not overlap. Designers should review the spacing of anchors and take into account of any overlapping cones (i.e. avoid doubling-up on rock mass calculations for overlapping cones). The bulk unit weight of bedrock may be assumed to be approximately 26 kn/m 3. The corresponding buoyant unit weight would be approximately 16 kn/m 3. Inspec-Sol recommends that independent monitoring by geotechnical engineer be carried out during the installation of the anchors to monitor depths, diameters, and quality of installation as well as the grouting of the anchors. Proof testing of anchors is recommended to be carried out by the Contractor and monitored by the Geotechnical Engineer following the grouting. The testing should be completed prior to pile cap/grade beam foundation elements being installed. These types of permanent anchors should be designed with double corrosion protection by the manufacturer/installer Frost Protection All pile caps exposed to potential freezing and associated with heated areas of the building must be provided with at least 1.5 m of earth cover or its equivalent in insulation, in order to provide adequate protection against detrimental frost action. This required cover depth should be increased to 1.8 m for footings in unheated areas such as retaining walls for loading docks, signs, entrance canopy, piers or underground parking garage entrances. The soils encountered in the boreholes are considered to be frost-susceptible. Should construction take place during winter, the exposed surfaces to support foundations must be protected by Contractors against freezing. Furthermore, the piles themselves are susceptible to frost adhesion and uplift, and this will need to be prevented in the case of winter construction. If piles are driven prior to general basement excavation, it is recommended that this be done in warm conditions Seismic Site Classification In accordance with OBC-2006, the building and its structural elements must be designed to resist a minimum earthquake force. In order to provide a site class, a geophysical (MASW) testing program that included the generation of dispersion curves, inversion of the obtained dispersion curves, and development of one dimensional (1-D) shear wave velocity profiles using SurfSeis version The dispersion curves obtained from active data using short, 14 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

27 medium, and long arrays along each investigation line were investigated and integrated to obtain a combined dispersion curve. In accordance with the requirements of OBC-2006, the variation of the measured shear wave velocity versus depth up to 33.5 m below existing ground elevation was obtained at each station, and is shown in Seismic Site Classification attached as Appendix: A, at the end of this report. The average shear wave velocity along each line was obtained utilizing the averaging scheme shown in Sentence (2) of Commentary J of National Building Code (NBC-2005) User s Guide. Based upon the results of the geophysical testing program, we recommend that the building be designed to Site Class D, with respect to Table A of the OBC The results of the geophysical testing program as well as the Seismic Site Class Calculation can be found in Seismic Site Classification attached as Appendix: A at the end of this report. In addition to the above geophysical testing program, it should be noted that no soil range of 3 m or more, was found within the borehole locations which would be considered as soft soils as defined in Table A of OBC In order to be considered as soft soils all of the following criteria must be satisfied: Plastic Index: Ip > 20%; Moisture Content: w 40%; and Undrained Shear: Strength Su < 25 kpa. 7.5 Lateral Earth Pressures Basement walls with soil backfill are to be considered as retaining walls and should be designed to withstand lateral earth pressures. If granular materials are placed between soil and poured concrete walls then the walls should be designed for lateral pressures resulting from the following sources: Unit weight of the backfilled soil; Temporary and permanent vertical loads on the completed ground surface; and Lateral loads due to backfill compaction equipment. Geotechnical Investigation Report 15 Ref. No.. : T A2 June 5, 2013

28 7.5.1 Static Conditions TABLE 4: Lateral Earth Pressures Coefficients Under Static Conditions Soil Bulk Internal Unit Friction Weight ( ) (kn/m 3 ) K a K o K p Compacted granular backfill such as an OPSS Granular BI or BII type product * The resultant force acts at a height of 0.3 H above the base of the wall under static conditions. This is based on the assumption that there is a perimeter drainage system installed at the base of the wall to prevent the build-up of hydrostatic pressure Dynamic Conditions The total active thrust under seismic loading (P ae ) is recommended to be expressed as follows: P ae = ½ K ae γ H 2 This includes both the active pressures under static (P a ) as well as the increased force due to seismic or simply as follows, P a = ½ K a γ H 2 Therefore, the seismic force (P e ) is simply the difference between the P ae and P a, or P e = P ae - P a The active force under static conditions is assumed to act at a point of 0.3H above the base and the seismic force is assumed to act near 0.6H above the base, where H is the height of the wall. Therefore the point of applying P ae may be calculated from the following: h = [(0.3H x P a) + (0.6H x P e )]/ P ae Therefore, for this Site we have recommended values of K ae = 0.96 and Ka = Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

29 This condition applies for open cut excavations and granular drained backfill behind the walls. 7.6 Permanent Drainage Both perimeter and under floor drainage is considered necessary for a structure with a basement floor slab set below the surrounding grades. Recommended Perimeter Drainage Alternatives are attached as Dwg No.: T A Perimeter Drainage and Foundation Wall Waterproofing Even if a composite drainage blanket or geodrain is used, it is still recommended that the exterior foundation walls be backfilled with a free-draining non frost susceptible soil. The perimeter drains should be connected to a frost-free outlet for year round drainage. They should not be connected to the interior under-floor drainage system. The options for a perimeter drainage system are to use conventional drainage tile or use a composite drainage blanket such as Miradrain 6200 or equivalent. As portions of the structure are below the water table, it is also recommended that the exterior walls be protected with a waterproofing membrane applied to the wall along with the composite drainage blanket. The geodrain product should be compatible with the waterproofing product. The waterproofing product could consist of a spray-on or mop-on waterproofing product or a peel and stick membrane such as a Soprema Colophene 3000 or equivalent. In areas on the building exterior where an asphalt or concrete pavement will not be present adjacent to the foundation wall, the upper 0.3 m of the exterior foundation wall backfill should be a low permeable soil to reduce surface water infiltration. Exterior grades should be sloped away from the foundation wall. Geotechnical Investigation Report 17 Ref. No.. : T A2 June 5, 2013

30 7.6.2 Under-Floor Waterproofing Based on the elevation of the water table we recommend a water proofing membrane such as a WR Meadows MEL-ROL PRECON or equivalent for under-slab. These types of membranes adhere to the underside of the slab-on-grade and provide a waterproof seal between the membrane and poured concrete slab. Water stops should be installed at cold joints in the foundation walls and floor wall joint. This product is suitable to be placed directly upon a Granular A surface which is adequately compacted to achieve 100 % of its standard proctor maximum dry density. The product should be installed in accordance with the manufacturer s recommendations (i.e. lap length, ambient temperature, openings, etc.). Inspec-Sol recommends a Site visit with the manufacturer s representative to review the installation details before the product is placed. The Client may also wish to consider periodic inspections during installation to verify the installation methods and ensure that the installations meet with the intent of the design. 7.7 Building Backfill The placement and compaction of the materials that will support footings, floor slabs, or any interior backfill must be treated as Engineered Fill. Compaction equipment must be of size and distance away to prevent damage to the walls during the time of placement Engineered Fill The fill operations for Engineered Fill must satisfy the following criteria. Engineered Fill must be placed under the continuous supervision of the Geotechnical Engineer. Prior to placing any Engineered Fill, all unsuitable subgrade materials must be removed, and the subgrade proof rolled, and approved. Any deficient areas should be repaired; Prior to the placement of Engineered Fill, the source or borrow areas for the Engineered Fill must be evaluated for its suitability. Samples of proposed fill material must be provided to the Geotechnical Engineer and 18 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

31 tested in the geotechnical laboratory for Standard Proctor Maximum Dry Density (SPMDD) and grain size, prior to approval of the material for use as Engineered Fill. The Engineered Fill must consist of environmentally suitable soils (as per industry standard procedures of federal or provincial guidelines/regulations), free of organics and other deleterious material (building debris such as wood, bricks, metal, and the like), compactable, and of suitable moisture content so that it is within -2% to +0.5% of the Optimum Moisture as determined by the Standard Proctor test. Imported granular soils meeting the requirements of Granular A, Granular B Type I or Type II OPSS 1010 criteria would be suitable; The Engineered Fill must be placed in maximum loose lift thicknesses of 0.2 m. Each lift of Engineered Fill must be compacted with a heavy roller to 100% SPMDD; Field density tests must be taken by the Geotechnical Engineer, on each lift of Engineered Fill. Any Engineered Fill, which is tested and found to not meet the specifications, shall be either removed or reworked and retested; and The lateral extent of Engineered Fill beneath foundations should be equivalent to 1.5 D from any edge of the foundation, where D is depth of the Engineered Fill below the footings Exterior Foundation Wall Backfill The backfill placed against the foundation walls should be free draining granular materials meeting the grading requirements of OPSS 1010 for Granular B Type I specifications up to within 0.3 m of the ground surface. The upper 0.3 m should be a low permeable soil to reduce surface water infiltration. Exterior foundation wall backfill should be placed and compacted as outlined below: Free-draining granular backfill should be used for the foundation wall; Backfill should not be placed in a frozen condition, or place on a frozen subgrade; Backfill should be placed and compacted in uniform lift thickness compatible with the selected construction equipment, but not thicker than 0.2 m. Backfill should be placed uniformly on both sides of the foundation walls to avoid build-up of unbalanced lateral pressures; Geotechnical Investigation Report 19 Ref. No.. : T A2 June 5, 2013

32 At exterior flush door openings the underside of sidewalks should be insulated, or the sidewalk should be placed on frost walls to prevent heaving. Granular backfill should be used and extended laterally beneath the entire area of the entrance slab. The entrance slab should slope away from the building; For backfill that would underlie paved areas, sidewalks or exterior slabson-grade, each lift should be uniformly compacted to at least 98% of its SPMDD; For backfill on the building exterior that would underlie landscaped areas, each lift should be uniformly compacted to at least 95% of its SPMDD; In areas on the building exterior where an asphalt or concrete pavement will not be present adjacent to the foundation wall, the upper 0.3 m of the exterior foundation wall backfill should be a low permeable soil to reduce surface water infiltration; and Exterior grades should be sloped away from the foundation wall, and roof drainage downspouts should be placed so that water flows away from the foundation wall. 7.8 Floor Slabs Conventional slab-on-grade construction is considered suitable for the proposed building subject to the Site grades not being raised. Preparation of the subgrade would include removal of loose or deleterious materials to expose the suitable subsoil. Any local weakened or soft areas should be excavated and replaced with suitable fill and compacted. Field verification should be carried out by geotechnical personnel during construction. A capillary moisture barrier consisting of a layer of either 19 mm clear stone or Granular A at least 200 mm thick should underlie the slabs. This layer should be compacted to 100% of its SPMDD and placed on approved subgrade surfaces. It is likely that a piling pad of at least 0.5 to 0.75 m of granular will be required to allow support to the piling equipment. As stated previously, waterproofing membrane is recommended to keep the basement dry. This will effect concrete finishing and saw cutting. Floor toppings may also be impacted by curing and moisture conditions of the concrete. Floor finish manufacturer s specifications and requirements should be consulted and procedures outlined in the specifications should be followed. 20 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

33 The slabs should be free floating, and should not be tied into the foundation walls. The placement of construction and control joints in the concrete should be in accordance with generally accepted practice. 7.9 Underground Services Bedding and Cover Bedding, spring-line, and cover should conform in size and type to local municipal requirements. The following are recommendations for service trench bedding and cover materials: Bedding for buried utilities should be OPSS Granular A or B Type II as applicable, and placed in accordance with City of Ottawa specifications; Use of clear 19 mm stone is not recommended for use as bedding. The voids in the stone may result in a low gradient water flow and infiltration of fines from the surrounding soils and cover materials, causing settlement and loss of support to pipes and structures; The cover material should be a sand material or Granular A and the dimensions should comply with City of Ottawa standards; The bedding material and cover materials should be compacted as per City of Ottawa standards and to at least 95% of its SPMDD; and Compaction equipment should be used in such a way that the utility pipes are not damaged during construction Service Trench Backfill Backfill above the cover for buried utilities should be in accordance with the following recommendations: Clay plugs should be incorporated along any service lines to prevent these to act as drainage conduits. The plugs should be placed at 10 m apart and/or at property lines mid-way between CB/MH. For service trenches under pavement areas, the backfill should be placed and compacted in uniform thickness compatible with the selected compaction equipment and not thicker than 200 mm. Each lift should be compacted to a minimum of 95% SPMDD; Geotechnical Investigation Report 21 Ref. No.. : T A2 June 5, 2013

34 The backfill placed in the upper 300 mm below a pavement subgrade elevation should be compacted to a minimum of 100% SPMDD; To reduce the potential for differential settlement and frost heave, the selected backfill materials should reasonably match the existing soil profile within the frost penetration zone (1.5 m below finished grade). Alternatively, if imported backfill, including granular materials, are used then the excavation sides should have frost tapers as per OPSD 800 series which essentially indicates that there should be a backslope of 10:1 (H:V) from the bedding grade to the finished grade; If the native excavated soils are used as backfill, this material should be protected from moisture increases during construction. The native excavated soils may should be assessed and approved by a Geotechnical Engineer prior to placement; and Excavated soils that are too wet (i.e. greater than 5% above the optimum moisture content based upon a Standard Proctor Test) will become problematic to compact and may not perform properly during construction period. If such conditions occur, the options include drying of the soils; compacting and leaving the area untraveled for a period of time; importation of more suitable material; or a combination of above and the use of geotextiles at the base and possibly additional layers within the pavement structure s granular base courses. The appropriate measures will need to be discussed during construction period and be such to achieve adequate performance from the pavement structure Pavement Sections In order to prepare the Site for the pavement area, it is necessary that the area be stripped of surficial topsoil, root-mat, and any fill soils or other deleterious materials to expose a suitable native subgrade. The exposed subgrade should be proof rolled in the presence of a Geotechnical Engineer, who will assess where soft spots, rutting, local anomalies, or significant deflection are and such areas may need to be excavated and replaced with suitable fill. Suitable fill would be an inorganic compatible fill and ideally should be a well graded granular material such as a crushed limestone quarry product meeting OPSS Granular A specification. The suitable fill should be compacted to at least 95% of its SPMDD. The use of geotextiles may be warranted for strength improvement. 22 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

35 The pavement sections described in Table 5 below are general recommendations and for areas subjected to parking lot and access road traffic. Alternative designs would require additional testing and analysis. TABLE 5: Recommended Pavement Structure Pavement Layer Minimum Thickness (Parking Stalls) Heavy Duty (Access Roads) HL3 Asphalt 50 mm 50 mm HL8 Asphalt n/r 50 mm Granular A Base Course 150 mm 150 mm Granular B, Type II Sub-Base Course 300 mm 450 mm In order to accommodate the recommended thicknesses, designers will need to review grades and determine where stripping or filling is necessary. Pavement materials and workmanship should conform to the appropriate OPSS. Drainage of the pavement layers is important. The subgrade surface and each layer of the pavement section should be provided with a suitable cross fall (approximately 2%) to prevent water from ponding on the pavement surface and beneath the pavement layers. Surface runoff should be directed to storm sewers, or allowed to flow into ditches. Sufficient field-testing should be carried out during construction to assess compaction of each lift of the pavement layers. This should be accompanied by laboratory testing of the granular and asphalt materials. All granular base course materials should be compacted to 100% of its SPMDD. Annual or regular maintenance will be required to achieve maximum life expectancy. Generally, the asphalt pavement maintenance will involve crack sealing and repair of local distress. It should be noted that the pavement sections described within this report represent end-use conditions only, which includes light vehicular traffic and occasional garbage or service trucks. It may be necessary that these sections be temporarily over-built during the construction phase to withstand larger construction loadings such as loaded dump trucks or concrete trucks. Geotechnical Investigation Report 23 Ref. No.. : T A2 June 5, 2013

36 8.0 CONSTRUCTION FIELD REVIEW The recommendations provided in this report are based on an adequate level of construction monitoring being conducted during construction phase of the proposed building. Inspec-Sol requests to be retained to review the drawings and specifications, once complete, to verify that the recommendations within this report have been adhered to, and to look for other geotechnical problems. Due to the nature of the proposed development, an adequate level of construction monitoring is considered to be as follows: A qualified Technologist acting under the supervision of a Geotechnical Engineer should monitor placement of Engineered Fill underlying floor slabs on a full time basis; Backfilling operations should be conducted in the presence of a qualified Technologist on a part time basis, to ensure that proper material is employed and specified compaction is achieved; Placement of concrete should be periodically tested to ensure that job specifications are being achieved; Piling operations should be monitored on a full time basis by a qualified Technologist to verify locations, verticality, and to ensure that the refusal criteria is being achieved; Pile Driving Analysis (PDA) should be performed at the start of pile driving to confirm the refusal criteria established for this project; Rock anchor installation should be monitored by a qualified technologist on a full-time basis to ensure that holes remain clean, and to verify that specified bond lengths are being achieved; and A program of proof and performance testing should be carried out on all anchors to ensure that they achieve the specified design capacity. 9.0 REPORT CONDITIONS AND LIMITATIONS This report is intended solely for Viva Retirement Communities and other parties explicitly identified in the report, and is prohibited for use by others without Inspec-Sol s prior written consent. This report is considered Inspec-Sol s professional work product and shall remain the sole property of Inspec-Sol. Any unauthorized reuse, redistribution of or reliance on the report shall be at the Client and recipient s sole risk, without liability to Inspec-Sol. Client shall defend, indemnify and hold Inspec-Sol harmless from any liability arising from or related to Client s unauthorized distribution of the report. No portion of this report may be 24 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

37 used as a separate entity; it is to be read in its entirety and shall include all supporting drawings and appendices. The recommendations made in this report are in accordance with our present understanding of the project, the current Site use, ground surface elevations and conditions, and are based on the work scope approved by the Client and described in the report. The services were performed in a manner consistent with that level of care and skill ordinarily exercised by members of geotechnical engineering professions currently practicing under similar conditions in the same locality. No other representations, and no warranties or representations of any kind, either expressed or implied, are made. Any use which a third party makes of this report, or any reliance on or decisions to be made based on it, are the responsibility of such third parties. All details of design and construction are rarely known at the time of completion of a geotechnical study. The recommendations and comments made in the study report are based on our subsurface investigation and resulting understanding of the project, as defined at the time of the study. We should be retained to review our recommendations when the drawings and specifications are complete. Without this review, Inspec-Sol will not be liable for any misunderstanding of our recommendations or their application and adaptation into the final design. By issuing this report, Inspec-Sol is the geotechnical engineer of record. It is recommended that Inspec-Sol be retained during construction of all foundations and during earthwork operations to confirm the conditions of the subsoil are actually similar to those observed during our study. The intent of this requirement is to verify that conditions encountered during construction are consistent with the findings in the report and that inherent knowledge developed as part of our study is correctly carried forward to the construction phases. It is important to emphasize that a soil investigation is, in fact, a random sampling of the Site and the comments included in this report are based on the results obtained at the five (5) borehole locations on the Site only. The subsurface conditions confirmed at these five (5) test locations may vary at other locations. Soil and groundwater conditions between and beyond the test locations may differ both horizontally and vertically from those encountered at the test locations and conditions may become apparent during construction, which could not be detected or anticipated at the time of our investigation. Should any conditions at the Site be encountered which differ from those found at the test locations, we request that we be notified immediately in order to permit a reassessment of our recommendations. If Geotechnical Investigation Report 25 Ref. No.. : T A2 June 5, 2013

38 changed conditions are identified during construction, no matter how minor, the recommendations in this report shall be considered invalid until sufficient review and written assessment of said conditions by Inspec-Sol is completed. SD/nc 26 Geotechnical Investigation Report Ref. No. : T A2 June 5, 2013

39 Drawings Site Location Plan Borehole/Rock Probe Location Plan MASW Line Layout Perimeter Drainage Alternative T A2-1 T A2-2 T A2-3 T A2-4

40 Jockvale Road Cedarview Road Beddington Avenue Shiregreen Drive Stradwick Avenue Jockvale Road Perrin Avenue Melville Drive Fable Street Whela n D r Larkshire Lane i ve Sherw ay Drive Dolan Drive Antler Avenue Glacier Street Wessex Road Alberni Street Maravista Drive Flanders Street Weybridge Drive Hopkinton Street Hummingbird Crescent Constable Stree Bourne Street Lim t Pickwick Drive. a Way Birkett Street Bentbrook Crescent Exeter Drive Starling Crescent Chester Crescent Pe a c ock Crescent W heeler Street Tow nsend Drive Prem Circle t Muskan Stree Kennevale Drive Lamplighters Drive Temporary Sarrazin Way Merner Avenue Hennepin Street Vesta Street Houlahan Street Atoll Street Rueter Street Tartan Drive Halley Street Pepperrall Crescent Opal Lane Strandherd Drive Waterlilly Way Madrid Avenue Haydon Circle Strandherd Drive Harthill Way Mckenna Casey Drive SITE Gorman Drive Cedarview Road HWY 416 Cambrian Road Source: MNR NRVIS, Produced by CRA under licence from Ontario Ministry of Natural Resources, Queen's Printer 2008 Datum: NAD 83 Projection: UTM Zone 18 SITE LOCATION PLAN GEOTECHNICAL INVESTIGATION 275 TARTAN DRIVE, OTTAWA, ONTARIO Dwg. No. T E2-1 T E2(001)GIS-OT001 November 10, 2011

41 GORMAN DRIVE.!' BH-7!' BH-2!' MW-1!' BH-8!' BH-3!' BH-4!' MW-6!' BH-5 STRANDHERD DRIVE Source: MNR NRVIS, Produced by CRA under licence from Ontario Ministry of Natural Resources, Queen's Printer 2008 Datum: NAD 83 Projection: UTM Zone 18 T E2(001)GIS-OT002 November 10, 2011 BOREHOLE LOCATION PLAN GEOTECHNICAL INVESTIGATION 275 TARTAN DRIVE, OTTAWA, ONTARIO Dwg. No. T E2-2

42 GORMAN DRIVE LINE 2. LINE 1 STRANDHERD DRIVE Source: MNR NRVIS, Produced by CRA under licence from Ontario Ministry of Natural Resources, Queen's Printer 2008 Datum: NAD 83 Projection: UTM Zone 18 T A2(001)GIS-OT001 November 24, 2011 MASW LINE LAYOUT GEOTECHNICAL INVESTIGATION 275 TARTAN DRIVE, OTTAWA, ONTARIO Dwg. No. T A2-3