Krosno Creek Flood Reduction Project
PROJECT FILE REPORT
CITY OF PICKERING
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Appendix H
Geotechnical Investigation
Report
TMIG | THE MUNICIPAL INFRASTRUCTURE GROUP LTD _____________________________________________________________________________
Draft Report on Geotechnical Investigation Proposed Replacement of Three Culverts of Krosno Creek At Morden Lane, Reytan Boulevard and Alyssum Street Pickering, Ontario D
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Prepared For: TMIG 8800 Dufferin Street, Suite 200 Vaughan, Ontario L4K 0C5 SPL Project No.:10000247‐110 July 3, 2014 © 2014 SPL Consultants Limited Table of Contents 1. INTRODUCTION ..................................................................................................................................... 1 2. FIELD AND LABORATORY WORK ........................................................................................................... 1 3. SUBSURFACE CONDITIONS .................................................................................................................... 2 3.1 Culvert at Morden Lane (BH14‐1 & BH14‐2) ................................................................................ 2 3.1.1 Soil Conditions....................................................................................................................... 2 3.1.2 Groundwater Conditions....................................................................................................... 4 3.2 Culvert at Reytan Boulevard (BH14‐3 & BH14‐4) ......................................................................... 5 Soil Conditions....................................................................................................................... 5 3.2.2 Groundwater Conditions....................................................................................................... 7 ra
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3.2.1 3.3 Culvert at Alyssum Street (BH14‐5 & BH14‐6) .............................................................................. 7 Soil Conditions....................................................................................................................... 7 3.3.2 Groundwater Conditions....................................................................................................... 8 DISCUSSION AND RECOMMENDATIONS ........................................................................................... 8 D
4. 3.3.1 4.1 FOUNDATIONS .............................................................................................................................. 9 4.1.1 Discussion on Foundation Options ....................................................................................... 9 4.1.2 Recommended Culvert Foundations .................................................................................. 10 4.2 EARTH PRESSURES AND BACKFILLING ........................................................................................ 11 4.3 SCOUR AND EROSION PROTECTION ........................................................................................... 12 4.4 CONSTRUCTION COMMENTS ...................................................................................................... 13 4.5 FROST PROTECTION .................................................................................................................... 14 5. GENERAL COMMENTS AND LIMITATIONS OF REPORT ....................................................................... 14 Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 Drawings 1 2 3 4 5 to 10 11 D
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Borehole Location Plan for Culvert at Morden Lane Borehole Location Plan for Culvert at Reytan Boulevard Borehole Location Plan for Culvert at Alyssum Street General Notes on Sample Descriptions Borehole Logs Gradation Curves Appendix A: General Comments on Shale Bedrock Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 1 1. INTRODUCTION SPL Consultants Limited (SPL) was retained by TMIG to carry out a geotechnical investigation for the proposed replacement of three culverts of Krosno Creek at Morden Lane, Reytan Boulevard and Alyssum Street in Pickering, Ontario. It is understood that the three existing CSP culverts will be replaced with twin 3m wide X 1.8m high concrete box culverts. It is also understood that there will not be any grade raise at the culvert locations / road levels. The objectives of the investigation were to determine the subsurface conditions at the locations of the proposed culverts by means of exploratory boreholes, and to provide geotechnical recommendations for the design and construction of the new culvert structures. ra
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This report is provided on the basis of the terms of reference presented above and on the assumption that the design will be in accordance with applicable codes and standards. If there are any changes in the design features relevant to the geotechnical analyses, or if any questions arise concerning the geotechnical aspects of the codes and standards, this office should be contacted to review the design. It may then be necessary to carry out additional borings and reporting before the recommendations of this office can be relied upon. 2. D
This report has been prepared for TMIG, Durham Region and their designers. Third party use of this report without SPL Consultants Limited consent is prohibited. The limitations conditions presented in this report form an integral part of the report and they must be considered in conjunction with this report. FIELD AND LABORATORY WORK The fieldwork for this project was performed in May 2014 and consisted of drilling and sampling six boreholes to depths varying from 11.1 to 12.8 m below the existing grades. The locations of the boreholes at the site are shown on the borehole location plans (Drawing Nos. 1, 2 and 3). The borehole locations and depths at each culvert location are as follows: 
Two boreholes (BH14‐1 and BH14‐2) were drilled on Morden Lane to a depth of 12.3m. 
Two boreholes (BH14‐3 and BH14‐4) were drilled on Reytan Boulevard to a depth of 12.3m. 
Two boreholes (BH14‐5 and BH14‐6) were drilled on Alyssum Street to depths varying from 11.1 to 12.8 m. The borehole locations were established in the field by SPL engineering staff. Prior to drilling operations, all underground utilities were cleared at the borehole locations by representatives of the public utilities locate companies. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 2 Boreholes were advanced using a truck‐mounted drilling rig owned and operated by Drilltech of Newmarket, Ontario, under the full‐time supervision of technical personnel from SPL. The boreholes were advanced using solid‐stem augers. Samples in the boreholes were taken at frequent intervals of depth by the Standard Penetration Test method (SPT), in general accordance with ASTM D1586. The test consists of freely dropping a 63.5 kg hammer a vertical distance of 0.76 m to drive a 51 mm O.D. split barrel (SS‐split‐spoon) sampler into the ground. The number of blows of the hammer required to drive the sampler into the relatively undisturbed ground by a vertical distance of 0.30 m is recorded as the Standard Penetration Resistance or the N‐value of the soil which is indicative of the compactness condition of granular (or cohesionless) soils (gravels, sands and silts) or the consistency of cohesive soils (clays and clayey soils). The samples were logged in the field and returned to the SPL Consultants Limited laboratory for detailed examination by the project engineer and for laboratory testing. In‐situ field vane shear tests were conducted in the weak silty clay deposit as shown on the borehole logs. ra
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As well as visual examination in the laboratory, all samples were tested for moisture contents. Selected five soil samples were subjected to grain size analysis and their gradation curves are presented on Drawing 11 of this report. Selected four soil samples were subjected to Atterberg limits testing and the results are presented on the respective borehole logs. Groundwater conditions in the boreholes were observed during and on completion of drilling in the open boreholes. One monitoring well was installed at each culvert location (BH14‐1, BH14‐4, and BH14‐
5) to determine the stabilized groundwater level over a prolonged period of time. The ground surface elevations at the borehole locations were measured by SPL personnel. SUBSURFACE CONDITIONS D
3. Details of the subsurface conditions encountered in the boreholes are presented on the borehole logs, Drawings 5 to 10. General notes on samples descriptions are presented on Drawing 4. The following description of the individual soil strata is to assist the designers of the project with an understanding of the anticipated subsurface conditions underlying the site. It should be noted that the soil and groundwater conditions may vary in between and beyond borehole locations. The summarized subsurface conditions for each culvert location are described in the following paragraphs. 3.1 Culvert at Morden Lane (BH14‐1 & BH14‐2) 3.1.1 Soil Conditions In general, below the topsoil and fill, the boreholes encountered weak silty clay deposit, overlying silty sand till, underlain by bedrock. Details of the subsurface conditions encountered in the boreholes are presented in the individual borehole logs, Drawings 5 and 6, and are briefly summarized below. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 3 Topsoil/Fill Material Topsoil layer, about 175 to 250 mm thick, was encountered in the boreholes at surface. Fill material consisting of clayey silt to silty clay was encountered in both the boreholes below topsoil, extending to a depth of 2.7m. Trace to some topsoil / organics inclusions were noted in the fill material. Fill material was present in a firm to stiff consistency, with measured SPT ‘N’ values ranging from 4 to 15 blows per 300 mm of penetration. Measured moisture content in the tested fill samples ranged from 10 to 26%. Silty Clay Below the fill material in the boreholes, upper native soil consisting of silty clay was encountered, extending to depths varying from 5.0 to 5.6m. Silty clay deposit was present in a firm to stiff consistency, with measured SPT ‘N’ values ranging from 2 to 10 blows per 300 mm of penetration. Measured moisture content in the tested silty clay samples ranged from 20 to 32%. ra
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As shown on the borehole logs, three (3) vane shear tests were conducted in the silty clay deposit, with measured undrained shear strength ranging from 35 to over 100 kPa. Two grain size analyses were carried out on the selected silty clay samples (BH14‐1/SS5 and BH14‐
2/SS5). The results are presented on the borehole logs, and the gradation curves are presented in Drawing 11, with the following fractions: Clay: Silt: Sand: 34 to 38% 59 to 64% 2 to 3% D
Atterberg Limits tests were performed on two samples (BH14‐1/SS5 and BH14‐2/SS5) from the silty clay deposit. The results are shown on the borehole logs and are summarized as follows: Liquid Limit: Plastic Limit: Plasticity Index: 30 to 31% 18% 12 to 13% The soil is classified as inorganic clay of low plasticity (CL). Silty Sand Till Below the silty clay in the boreholes, silty sand till deposit was encountered, overlying shale bedrock. Silty sand till was present in a compact to very dense state, with measured SPT ‘N’ values ranging from 15 to over 50 blows per 300 mm of penetration. Measured moisture content in the tested silty sand till samples ranged from 5 to 10%. A 300 mm thick silty sand layer was encountered in BH14‐1 at a depth of 5.2m, above silty sand till. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 4 Grain size analysis was carried out on selected silty sand till sample (BH14‐1/SS7). The results are presented on the borehole log, and the gradation curves are presented in Drawing 11, with the following fractions: Clay: Silt: Sand: Gravel: 14% 39% 42% 5% Shale Bedrock The shale bedrock was encountered in both the boreholes, at depths ranging from 11.0 to 12.2 m from the existing grade. The shale bedrock was not proven by rock core drilling. The depth and elevation of the shale bedrock surface in the boreholes are listed on Table 1 below. Table 1: Depth and Elevation of Shale Bedrock Surface Depth of Shale Bedrock Surface below Existing Ground (m) Approximate Elevation of Shale Bedrock Surface (m) Notes BH14‐1 12.2 68.1 Augered 11.0 69.5 Augered BH14‐2 ra
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Borehole No. D
Commonly the till overlying the shale contains slabs of limestone which would give a false indication of the bedrock level. Similarly the depth of weathering cannot be determined accurately due to the presence of limestone layers. The shale bedrock generally contains layers of sandstone, limestone and dolostone. Typically the hard layers comprise about 10 to 20 percent of the unit. However, higher concentrations of hard layers can be present. The hard layers are usually less than 100 to 150 mm thick but some layers are much thicker. The thicker layers have been observed to be as much as 750 to 900 mm at other sites. The layers are actually lenses and they can vary significantly in thickness over short distance. Methane gas is anticipated in the bedrock. Appropriate care and monitoring is essential in all confined bedrock excavations, particularly for caissons. Stress relief features such as folds and faults are common in the shale bedrock. Appendix A presents more details and general comments about the shale bedrock. 3.1.2 Groundwater Conditions The observed short‐term groundwater levels in the boreholes upon completion of drilling varied from 3.7 to 4.6m below the existing grade. However, the groundwater table observed in the monitoring well installed in BH14‐1 was at a depth of 2.2m, corresponding to Elevation 78.1 m on June 18, 2014. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 5 It should be noted that the groundwater at the site would be subject to seasonal fluctuations as well as fluctuations due to weather events and the water level in the creek. 3.2 Culvert at Reytan Boulevard (BH14‐3 & BH14‐4) 3.2.1 Soil Conditions In general, below the topsoil and fill, the boreholes encountered weak silty clay deposit, overlying gravelly sand /sand followed by silty sand till, underlain by bedrock. Details of the subsurface conditions encountered in the boreholes are presented in the individual borehole logs, Drawings 7 and 8, and are briefly summarized below. Topsoil/Fill Material Silty Clay ra
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Topsoil layer, about 170 to 200 mm thick, was encountered in the boreholes at surface. Fill material consisting of clayey silt to silty clay and sandy silt was encountered in the boreholes, extending to depths varying from 2.0 to 2.8m. Trace to some topsoil / organics inclusions were noted in the fill material. Fill material was present in a firm to stiff consistency / compact state, with measured SPT ‘N’ values ranging from 4 to 18 blows per 300 mm of penetration. Measured moisture content in the tested fill samples ranged from 7 to 31%. D
Below the fill material in the boreholes, upper native soil consisting of silty clay was encountered, extending to depths varying from 7.6 to 9.4m. Silty clay deposit was present in a firm to very stiff, generally in firm to stiff consistency, with measured SPT ‘N’ values ranging from 2 to 23 blows per 300 mm of penetration. Measured moisture content in the tested silty clay samples ranged from 16 to 36%. As shown on the borehole logs, four (4) vane shear tests were conducted in the silty clay deposit, with measured undrained shear strength ranging from 30 to over 100 kPa. Grain size analysis was carried out on a selected silty clay sample (BH14‐3/SS6). The results are presented on the borehole log, and the gradation curves are presented in Drawing 11, with the following fractions: Clay: Silt: Sand: 41% 58% 1% Atterberg Limits test was performed on the same silty clay sample (BH14‐3/SS6). The results are shown on the borehole log and are summarized as follows: Liquid Limit: Plastic Limit: Plasticity Index: 29% 17% 12% Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 6 The soil is classified as inorganic clay of low plasticity (CL). Gravelly Sand/ Sand: A 900 mm thick gravelly sand layer was encountered in BH14‐3 at a depth of 7.6m, above silty sand till. Sand layer about 1.3m was encountered in BH14‐4 below silty clay and overlying silty sand till. Gravelly sand / sand were water bearing and present in a very loose to compact state. Grain size analysis was carried out on gravelly sand sample (BH14‐3/SS8 top portion). The results are presented on the borehole log, and the gradation curve is presented in Drawing 11, with the following fractions: Clay: Silt: Sand: Gravel: 5% 17% 52% 26% ra
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Silty Sand Till Below the gravelly sand or sand in the boreholes, silty sand till deposit was encountered extending to a depth of about 12.2m, overlying the shale bedrock in BH14‐3 and clayey silt in BH14‐4. Silty sand till was present in a dense to very dense state, with measured SPT ‘N’ values ranging from 30 to over 50 blows per 300 mm of penetration. Measured moisture content in the tested silty sand till samples ranged from 8 to 12%. Shale Bedrock D
The shale bedrock was encountered in BH14‐3 at a depth of 12.2m below the existing grade, corresponding to Elevation 66.6m. The shale bedrock was not proven by rock core drilling. Commonly the till overlying the shale contains slabs of limestone which would give a false indication of the bedrock level. Similarly the depth of weathering cannot be determined accurately due to the presence of limestone layers. The shale bedrock generally contains layers of sandstone, limestone and dolostone. Typically the hard layers comprise about 10 to 20 percent of the unit. However, higher concentrations of hard layers can be present. The hard layers are usually less than 100 to 150 mm thick but some layers are much thicker. The thicker layers have been observed to be as much as 750 to 900 mm at other sites. The layers are actually lenses and they can vary significantly in thickness over short distance. Methane gas is anticipated in the bedrock. Appropriate care and monitoring is essential in all confined bedrock excavations, particularly for caissons. Stress relief features such as folds and faults are common in the shale bedrock. Appendix A presents more details and general comments about the shale bedrock. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 7 3.2.2 Groundwater Conditions The observed short‐term groundwater levels in the boreholes upon completion of drilling varied from 2.7 to 4.3m depth. The stabilized groundwater table observed in the monitoring well installed in BH14‐4 was at a depth of 1.3m, corresponding to Elevation 77.7 m on June 18, 2014. It should be noted that the groundwater at the site would be subject to seasonal fluctuations as well as fluctuations due to weather events and the water level in the creek. 3.3 Culvert at Alyssum Street (BH14‐5 & BH14‐6) 3.3.1 Soil Conditions Topsoil/Fill Material ra
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In general, below the topsoil and fill, the boreholes encountered weak silty clay deposit, overlying silty sand / silty sand till, underlain by bedrock. Details of the subsurface conditions encountered in the boreholes are presented in the individual borehole logs, Drawings 9 and 10, and are briefly summarized below. Topsoil layer, about 100 to 180 mm thick, was encountered in boreholes at the surface. Fill material consisting of clayey silt to silty clay was encountered in both the boreholes, extending to a depth of 2.6m. Trace topsoil / organics inclusions were noted in the fill material. Fill material was present in a firm to stiff consistency, with measured SPT ‘N’ values ranging from 4 to 15 blows per 300 mm of penetration. Measured moisture content in the tested fill samples ranged from 9 to 23%. D
Clayey Silt to Silty Clay Below the fill material in the boreholes, upper native soil consisting of clayey silt to silty clay was encountered in both the boreholes, extending to depths varying from 9.1 to 9.5m. Clayey silt to silty clay was present in a soft to stiff consistency, with measured SPT ‘N’ values ranging from 2 to 15 blows per 300 mm of penetration. Measured moisture content in the tested clayey silt to silty clay samples ranged from 17 to 47%. As shown on the borehole log, a vane shear test was conducted in the silty clay deposit, with measured undrained shear strength of 46 kPa. Grain size analysis was carried out on selected clayey silt to silty clay sample (BH14‐5/SS6). The results are presented on the borehole log, and the gradation curve is presented in Drawing 10, with the following fractions: Clay: Silt: Sand: 23% 75% 2% Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 8 Atterberg Limits test was performed on the same sample (BH14‐5/SS6) from the clayey silt to silty clay deposit. The results are shown on the borehole log and are summarized as follows: Liquid Limit: Plastic Limit: Plasticity Index: 20% 14% 6% The soil is classified as inorganic clayey silt of low plasticity (CL‐ML). Silty Sand Below the clayey silt to silty clay in the boreholes, a silty sand layer was encountered, overlying silty sand till. Silty sand was water bearing and present in a loose to very dense state, with measured SPT ‘N’ values ranging from 6 to over 50 blows per 300 mm of penetration. Measured moisture content in the tested silty sand samples ranged from 10 to 12%. Silty Sand Till ra
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Silty sand till deposit was encountered in both the boreholes below silty sand, extending to the maximum explored depths. This deposit was present in a very dense state, with measured SPT ‘N’ values of over 50 blows per 300 mm of penetration. Measured moisture content in the tested silty sand till samples ranged from 5 to 7%. 3.3.2 Groundwater Conditions D
The observed short‐term groundwater levels in the boreholes upon completion of drilling varied from 3.7 to 4.6m depth. The stabilized groundwater table observed in the monitoring well installed in BH14‐5 was at a depth of 1.1m, corresponding to Elevation 77.1 m on June 18, 2014. It should be noted that the groundwater at the site would be subject to seasonal fluctuations as well as fluctuations due to weather events and the water level in the creek. 4. DISCUSSION AND RECOMMENDATIONS It is understood that the three existing CSP culverts will be replaced with twin 3m wide X 1.8m high concrete box culverts. It is also understood that there will not be any grade raise at the culvert locations and road levels will remain same as the present levels. At the culvert locations, the creek beds are generally 2.5 to 3m below the top of the road level. Proposed founding/invert elevations of the box culverts are presented Table 2. The traditional footing types for the concrete culverts are either “open” box, founded on native soil base by narrow strip footings, or “closed” box with an integral concrete base acting as the footing. As the culvert structures will be underlain by compressible soils, a closed box culvert is considered more appropriate in comparison to open box, in terms of its ability to tolerate more differential settlements. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 9 4.1 FOUNDATIONS Based on the subsurface conditions explored in the boreholes, geotechnical comments and recommendations for the culvert foundations are presented as follows. 4.1.1 Discussion on Foundation Options Similar soil conditions were encountered in the boreholes at locations of the three culverts. The native soils below some fill materials generally consisted of a layer of relatively weak (firm to stiff) silty clay, overlying sandy deposits (generally silty sand). In BH14‐1 to BH14‐4, shale bedrock was encountered at depths of 11 to 12 m. The groundwater table was generally at about 1 to 2 m below the existing grade. Based on the soil and groundwater conditions explored at the site, the following foundation options can be considered: Option‐1: Shallow foundations (footings and/or mat foundations) 
Option‐2: Deep foundations (Driven piles) ra
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Drilled caissons are not recommended for supporting the culverts, due to the presence of saturated sand deposits between the silty clay deposit and the shale bedrock. D
Footings (Option‐1) can be adopted for supporting the culverts, to be founded on the undisturbed silty clay deposit. The increased loading conditions from the concrete culvert structures will lead to the long‐
term (post‐construction) consolidation settlements of the underlying weak silty clay soils. The estimated total consolidation settlements of the weak silty clay encountered in the boreholes ranges from 30 to 50mm for the proposed culverts. In this case, the culverts will settle together with the approach fill. The differential settlement between the road surface over the culvert and the road surface adjacent to and beyond the culvert will be minimized. This magnitude of settlements should be tolerable for the proposed concrete culverts. More flexible CSP culverts can also be considered to better accommodate the anticipated settlement. Another way to reduce the post‐construction settlement of the culverts is to adopt preloading surcharge and wick drains to consolidate the ground before paving. Simple surcharging without wick drains can take a few years for the settlement to occur and may not be practical. Soil consolidation using wick drains can rapidly increase settlement rates and reduce the project durations drastically. SPL can provide detailed recommendations for preloading and wick drains, if required. Driven piles (Option‐2) founded in the very dense sand deposit or shale bedrock. However, this option is not preferred, mainly due to the concerns of high costs for the construction of the piles and the pile caps. In addition, the post‐construction settlement of the culverts supported by driven will be minimal. However, the approach fill adjacent to and beyond the culvert will settle with time. The differential settlement between the road surface over the culvert and the road surface adjacent to and beyond the culvert will essentially be the settlement of the approach fill. Some long‐term cracking of the pavement will occur along both sides of the culvert. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 10 It is recommended that the proposed culverts be supported by shallow foundations (footings or mat foundations) founded on the undisturbed silty clay deposits. 4.1.2 Recommended Culvert Foundations Based on the information obtained from the boreholes, the closed bottom culverts founded on the undisturbed native firm to stiff silty clay deposit can be designed for bearing capacity values of 120 kPa at SLS and 160 kPa at ULS. The bearing values and the corresponding founding elevations at the borehole locations for each culvert location are summarized on Table 2 below. Table 2: Bearing Values and Founding Levels of Culverts Culvert Invert Elev. (m) Morden Lane ~77.5 Reytan Blvd ~76.0 Alyssum Street ~75.5 BH No. BH14‐1 BH14‐2 BH14‐3 BH14‐4 BH14‐5 Founding Soils Silty Clay Silty Clay Silty Clay Silty Clay Silty Clay BH14‐6 Silty Clay Bearing Capacity at SLS (kPa) 120 120 120 120 120 120 Bearing Capacity at ULS (kPa) 160 160 160 160 160 160 Minimum Depth below Existing Ground (m) 3.0 3.0 3.0 2.3 2.9 Founding Level At or Below Elevation (m) 77.3 77.3 75.8 76.7 75.3 2.9 75.4 ra
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Culvert Location D
The post construction settlement of the culverts will mainly result from the consolidations of the silty clay deposits. Foundations designed to the specified bearing capacity of 120 kPa at SLS are expected to settle less than 30 to 50 mm total and 20 to 30 mm differential. The anticipated maximum settlements of the 3 proposed culverts are summarized on Table 3 below. Table 2: Estimated Settlements of Culverts for Bearing Capacity of 120 kPa at SLS Culvert Location Culvert Invert Elev. (m) Morden Lane ~77.5 Reytan Blvd Alyssum Street Borehole No. Approximate Thickness of Founding Silty Clay (m) Max. Total Settlement (mm) Max. Differential Settlement (mm) BH14‐1, BH14‐2 2 to 3 m 30 20 ~76.0 BH14‐3, BH14‐4 5 to 6 m 40 25 ~75.5 BH14‐5, BH14‐6 6 to 7 m 50 30 Bedding, cover and backfill details for the new culvert should be as per MTOD 803.021. Bedding for the new culvert may consist of either: Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 11 
500 mm of compacted Granular A or Granular B Type II; or 
300 mm of compacted Granular A or Granular B Type II placed over a lean concrete working slab. If constructed properly, either bedding treatment is considered adequate from a foundations perspective. A 75 mm levelling course of additional Granular A or fine aggregate should also be provided between the bedding and the culvert. In order to minimize the potential for piping and undermining of the culvert foundations the bedding should be wrapped in a non‐woven geotextile which meets the requirements of OPSS 1860. Cover for the new culverts should be a minimum of 300 mm thick and may include either Granular A or Granular B with a maximum particle size of 75 mm (as per OPSS 422 and Special Provision 422S01). EARTH PRESSURES AND BACKFILLING ra
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4.2 Backfilling behind culvert walls and any retaining (wing) walls should consist of granular materials in accordance with the applicable Standards. Free draining backfill materials, weepholes, etc. should be provided in order to prevent hydrostatic pressure build‐up. Backfilling around the culverts can consist of Granular ‘A’ or Granular ‘B’ material, placed in shallow lifts, not exceeding 200 mm loose thickness. Granular fill immediately below the roadway and adjacent to the culvert should be compacted to a minimum of 100% of their Standard Proctor Maximum Dry Density (SPMDD). Remaining fills may be compacted to a minimum of 98% of SPMDD. D
To avoid damaging or laterally dislocating it, care should be exercised for the compaction of the backfill adjacent to and immediately on top of the culvert structure and compaction equipment should be restricted in size. Computation of earth pressures acting against culvert walls, retaining walls and any wing walls should be in accordance with the Canadian Highway Bridge Design Code, (CHBDC) S6‐06. For design purposes, the following properties can be assumed for backfill. Compacted Granular ‘A’ or Granular ‘B’ Type II Angle of Internal Friction =35 (unfactored) Unit weight = 22 kN/m3 Coefficient of Lateral Earth Pressure: Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 12 Level Backfill Ka=0.27 Kb=0.35 Ko=0.43 K*=0.45 Backfill Sloping at 3H:1V Ka=0.34 Kb=0.44 Ko=0.56 K*=0.60 Backfill Sloping at 2H:1V Ka=0.40 Kb=0.50 Ko=0.62 K*=0.66 Compacted Granular ‘B’ Type I Angle of Internal Friction =32 (unfactored) Unit Weight = 21 kN/m3 Coefficient of Lateral Earth Pressure: Backfill Sloping at 3H:1V Backfill Sloping at 2H:1V Ka=0.31 Ka=0.39 Ka=0.47 Kb=0.39 Kb=0.49 Kb=0.57 Ko=0.47 Ko=0.62 Ko=0.69 K*=0.54 K*=0.68 K*=0.78 ra
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Note: Level Backfill Ka is the coefficient of active earth pressure Kb is the backfill earth pressure coefficient for an unrestrained structure including compaction efforts Ko is the coefficient of earth pressure at rest D
K* is the earth pressure coefficient for a soil loading a fully restrained structure and includes compaction effects These values are based on the assumption that the backfill behind the retaining structures is free‐
draining granular material and adequate drainage is provided. The earth pressure coefficient to be adopted will depend on whether the retaining structure is restrained or some movement can occur such that the active state of earth pressure can develop. The effect of compaction should also be taken into account in the selection of the appropriate earth pressure coefficients. The use of vibratory compaction equipment behind the culvert walls and the retaining walls should be restricted in size. 4.3 SCOUR AND EROSION PROTECTION Erosion and scour protection should be provided at the culvert inlet and outlet (including the slopes and sides). The erosion/scour protection should be designed by a specialist River Engineer/Scientist (as erosion and scour largely depend on the velocity of water in the watercourse and its regime) who is familiar with the findings of this report. The following are some general suggestions, considering that the subgrade could consist of erodible silty soils. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 13 We recommend that a concrete cut‐off (apron) be constructed both at the inlet and outlet to prevent seepage beneath and around the culvert. Beneath the culvert, the concrete cut‐off wall should extend to a suitable depth (e.g. below any possible scour depth). Consideration may also be given to an impervious seal at the inlet and outlet. At the inlet, consideration may also be given to the use of a clay seal. The purpose of the clay seal is to ensure that water flow is channeled through the culvert and does not seep through the backfill around the structure and from beneath the structure. The clay seal should therefore be continuous and typically 0.6 m thick. It should comply with the material specifications given in OPSS 1205. It should be extended around the culvert from at least 0.5 m above the high water level in the watercourse down to the channel bed and up the other side in a continuous manner. It should be ensured that it extends to cover all the granular backfill materials to prevent any seepage through them. Typically, the clay seal is protected by laying a 0.6 m thick rock protection over it. The clay seal would generally be extended at about 8 m beyond the inlet. 4.4 ra
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At the outlet as well as at the inlet (if clay seal is not used), in addition to the concrete cut‐off and/or impervious seal or in conjunction with these, a 0.6 m thick rock protection, consisting typically of 300 mm size rock can be considered. This would generally be extended about 8m along the channel and the sides (to at least 0.3 m above high water level). A geotextile separator (non‐woven, Class II FOS 75 to 150 m) should be placed behind the rockfill to prevent migration of fine particles into the rockfill due to seepage pressure. A toe for the filter and rip‐rap protection should be provided at the edge of the lining and protective cover to key the lining into the natural ground to provide protection to erosion and scour. CONSTRUCTION COMMENTS D
All excavations should be carried out in accordance with the Occupational Health and Safety Act (OHSA). The following soil classifications can be expected for temporary excavations in accordance with OHSA. Fill Weak Silty Clay : Type 3 soil above groundwater level and Type 4 soil below groundwater level. : Type 4 Soil below groundwater level Dewatering will be required to stabilize the soil and to facilitate construction where excavations are required below the groundwater table or creek level. It is our opinion that in the silty clay deposits, the groundwater can be controlled by means of gravity drainage and strategically spaced and located filtered sumps. A system of cofferdams to cut‐off the water flow from creek into the excavation may be required to assist in excavation. Water must be lowered to at least 0.5 m below the lowest excavation level. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 14 Possible large obstructions such as buried concrete pieces are also anticipated in the fill material. Provisions must be made in the excavation contract for the removal of possible obstructions in the fill material. Allowance should be made to place a skim‐coat of concrete (mud‐slab) once the excavation is completed, inspected and approved, without any delay. It is recommended that the joints of the pre‐cast concrete box culvert be wrapped with 2 layers of geotextile (such as Terrafix 400R or equivalent) in order to minimize any loss of fine soil through the joints. The length of the geotextile along the culvert alignment should be minimum 2.4 m, i.e. extending minimum 1.2 m beyond both sides of the joints. 4.5 FROST PROTECTION 5. ra
ft
Design frost protection for the general area is 1.2 m. A permanent soil cover of at least 1.2 m or its thermal equivalent is therefore required for frost protection. In case of riprap (rock fill), only one half of the rock fill thickness should be assumed to be effective in providing frost protection. GENERAL COMMENTS AND LIMITATIONS OF REPORT SPL Consultants Limited should be retained for a general review of the final design and specifications to verify that this report has been properly interpreted and implemented. If not accorded the privilege of making this review, SPL Consultants Limited will assume no responsibility for interpretation of the recommendations in the report. D
The comments given in this report are intended only for the guidance of design engineers. The number of boreholes required to determine the localized underground conditions between boreholes affecting construction costs, techniques, sequencing, equipment, scheduling, etc., would be much greater than has been carried out for design purposes. Contractors bidding on or undertaking the works should, in this light, decide on their own investigations, as well as their own interpretations of the factual borehole and test pit results, so that they may draw their own conclusions as to how the subsurface conditions may affect them. This report is intended solely for the Client named. The material in it reflects our best judgment in light of the information available to SPL Consultants Limited at the time of preparation. Unless otherwise agreed in writing by SPL Consultants Limited, it shall not be used to express or imply warranty as to the fitness of the property for a particular purpose. No portion of this report may be used as a separate entity, it is written to be read in its entirety. The conclusions and recommendations given in this report are based on information determined at the test hole locations. The information contained herein in no way reflects on the environment aspects of the project, unless otherwise stated. Subsurface and groundwater conditions between and beyond the test holes may differ from those encountered at the test hole locations, and conditions may become apparent during construction, which could not be detected or anticipated at the time of the site Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 15 investigation. The benchmark and elevations used in this report are primarily to establish relative elevation differences between the test hole locations and should not be used for other purposes, such as grading, excavating, planning, development, etc. The comments made in this report on potential construction problems and possible methods are intended only for the guidance of the designer. The number of test holes may not be sufficient to determine all the factors that may affect construction methods and costs. For example, the thickness of surficial topsoil or fill layers may vary markedly and unpredictably. The contractors bidding on this project or undertaking the construction should, therefore, make their own interpretation of the factual information presented and draw their own conclusions as to how the subsurface conditions may affect their work. This work has been undertaken in accordance with normally accepted geotechnical engineering practices. 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. SPL Consultants Limited accepts no responsibility for damages, if any, suffered by any third party as a result of decisions made or actions based on this report. D
ra
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We accept no responsibility for any decisions made or actions taken as a result of this report unless we are specifically advised of and participate in such action, in which case our responsibility will be as agreed to at that time. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 16 D
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We trust that the information contained in this report is satisfactory. Should you have any questions, please do not hesitate to contact this office. Yours very truly, SPL Consultants Limited Alka Sangar, M. Eng., P. Eng. Fanyu Zhu, Ph. D., P. Eng. Shabbir Bandukwala, M.Eng., P. Eng. Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 1 ra
ft
Drawings D
Geotechnical Investigation – Proposed Replacement of Three Culverts at Krosno Creek, Pickering, ON SPL Project No.:10000247‐110 July 3, 2014 Key Map (only for Dwg 1)
Site
Tabloid
24-Jun-14
Date:
Original
Size:
PM
Drawn:
Client:
BH14‐2
Rev:
Scale:
Approved:
TMIG
tf
a
r
D
BH14‐1
N/A
NTS
AS
Project:
Title:
Project No:
Drawing No:
1
Geotechnical Investigation - Proposed Replacement of Krosno Creek
Culverts, Pickering, ON
Borehole Location Plan - Morden Lane
10000247-110
Key Map (only for Dwg 2)
BH14‐3
D
Site
Tabloid
24-Jun-14
Date:
Original
Size:
PM
Drawn:
Client:
Rev:
Scale:
Approved:
TMIG
tf
a
r
BH14‐4
N/A
NTS
AS
Project:
Title:
Project No:
Drawing No:
2
Geotechnical Investigation - Proposed Replacement of Krosno Creek
Culverts, Pickering, ON
Borehole Location Plan - Reytan Boulevard
10000247-110
Key Map (only for Dwg 3)
Site
Tabloid
24-Jun-14
Date:
Original
Size:
PM
Drawn:
Client:
Rev:
Scale:
Approved:
TMIG
tf
a
r
BH14‐6
D
BH14‐5
N/A
NTS
AS
Project:
Title:
Project No:
Drawing No:
3
Geotechnical Investigation - Proposed Replacement of Krosno Creek
Culverts, Pickering, ON
Borehole Location Plan - Alyssum Street
10000247-110
Drawing 4: Notes On Sample Descriptions 1. All sample descriptions included in this report generally follow the Unified Soil Classification. Laboratory grain size analyses provided by SPL also follow the same system. Different classification systems may be used by others, such as the system by the International Society for Soil Mechanics and Foundation Engineering (ISSMFE). Please note that, with the exception of those samples where a grain size analysis and/or Atterberg Limits testing have been made, all samples are classified visually. Visual classification is not sufficiently accurate to provide exact grain sizing or precise differentiation between size classification systems. ISSMFE SOIL CLASSIFICATION
CLAY
FINE
0.002
SILT
MEDIUM
0.006
COARSE
0.02
SAND
MEDIUM
FINE
0.06
0.2
COARSE
0.6
GRAVEL
MEDIUM
FINE
2.0
6.0
COBBLES
BOULDERS
COARSE
20
60
200
EQUIVALENT GRAIN DIAMETER IN MILLIMETRES
CLAY (PLASTIC) TO
SILT (NONPLASTIC)
FINE
MEDIUM
SAND
CRS.
FINE
COARSE
GRAVEL
UNIFIED SOIL CLASSIFICATION
D
ra
ft
2. Fill: Where fill is designated on the borehole log it is defined as indicated by the sample recovered during the boring process. The reader is cautioned that fills are heterogeneous in nature and variable in density or degree of compaction. The borehole description may therefore not be applicable as a general description of site fill materials. All fills should be expected to contain obstruction such as wood, large concrete pieces or subsurface basements, floors, tanks, etc., none of these may have been encountered in the boreholes. Since boreholes cannot accurately define the contents of the fill, test pits are recommended to provide supplementary information. Despite the use of test pits, the heterogeneous nature of fill will leave some ambiguity as to the exact composition of the fill. Most fills contain pockets, seams, or layers of organically contaminated soil. This organic material can result in the generation of methane gas and/or significant ongoing and future settlements. Fill at this site may have been monitored for the presence of methane gas and, if so, the results are given on the borehole logs. The monitoring process does not indicate the volume of gas that can be potentially generated nor does it pinpoint the source of the gas. These readings are to advise of the presence of gas only, and a detailed study is recommended for sites where any explosive gas/methane is detected. Some fill material may be contaminated by toxic/hazardous waste that renders it unacceptable for deposition in any but designated land fill sites; unless specifically stated the fill on this site has not been tested for contaminants that may be considered toxic or hazardous. This testing and a potential hazard study can be undertaken if requested. In most residential/commercial areas undergoing reconstruction, buried oil tanks are common and are generally not detected in a conventional preliminary geotechnical site investigation. 3. Till: The term till on the borehole logs indicates that the material originates from a geological process associated with glaciation. Because of this geological process the till must be considered heterogeneous in composition and as such may contain pockets and/or seams of material such as sand, gravel, silt or clay. Till often contains cobbles (60 to 200 mm) or boulders (over 200 mm). Contractors may therefore encounter cobbles and boulders during excavation, even if they are not indicated by the borings. It should be appreciated that normal sampling equipment cannot differentiate the size or type of any obstruction. Because of the horizontal and vertical variability of till, the sample description may be applicable to a very limited zone; caution is therefore essential when dealing with sensitive excavations or dewatering programs in till materials. GEOTECHNICAL INVESTIGATION – REPLACEMENT OF KROSNO CREEK CULVERTS, ONTARIO
SPL PROJECT NO.: 10000247-110
DATE: JULY 3, 2014
LOG OF BOREHOLE BH14-1
1 OF 1
PROJECT: Geotechnical Investigation-Proposed Replacement of Three Culverts
DRILLING DATA
CLIENT: TMIG
Method: Solid Stem Auger
PROJECT LOCATION: Krosno Creek - Various Streets, Pickering, ON
Diameter: 150mm
REF. NO.: 10000247-110
DATUM: Geodetic
Date: May/20/2014
Drawing No.: 5
TOPSOIL: 250mm
FILL: silty clay mixed with topsoil,
trace sand, trace rootlets, trace
organic, trace gravel, brown, moist,
firm to stiff
40
60
80
100
FIELD VANE
& Sensitivity
LAB VANE
80
100
LIQUID
LIMIT
w
wP
SHEAR STRENGTH (kPa)
UNCONFINED
QUICK TRIAXIAL
20
40
60
NATURAL
PLASTIC
MOISTURE
LIMIT
CONTENT
wL
WATER CONTENT (%)
10
20
30
POCKET PEN.
(Cu) (kPa)
20
ELEVATION
GROUND WATER
CONDITIONS
"N" BLOWS
0.3 m
TYPE
80.3
0.0
80.1
0.3
DESCRIPTION
NUMBER
(m)
ELEV
DEPTH
DYNAMIC CONE PENETRATION
RESISTANCE PLOT
SAMPLES
STRATA PLOT
SOIL PROFILE
NATURAL UNIT WT
3
(Mg/m )
BH LOCATION: Morden Lane
REMARKS
AND
GRAIN SIZE
DISTRIBUTION
(%)
GR SA SI CL
Concrete
1
SS
4
2
SS
15
80
79
77.6
2.7
---------------------grey below 2.3m
SILTY CLAY: trace gravel, trace
sand, grey, moist, firm to stiff.
3
SS
10
4
SS
7
5
SS
10
7878.1 m
W. L.
Jun 18, 2014
77
SH
0
3 59 38
ra
ft
76
Holeplug
75.3
5.0
74.8
5.5
VANE
SILTY SAND: trace clay, trace
gravel, grey, wet, compact.
SILTY SAND TILL: some clay, trace
gravel, grey, moist, compact to very
dense
75
6
SS
27
7
SS
23
74
73
SS
56
D
8
72
trace shale fragments below 8.2m
9
SS
Sand
50/
100mm
71
70
10
SS
50/
50mm
Screen
SPL SOIL LOG 10000247 LOGS.GPJ SPL.GDT 4/7/14
69
68.1
68.0
12.2
12.3
SHALE BEDROCK: weathered,
blackish grey.
END OF THE BOREHOLE
Notes:
1) Borehole open and water level
4.6mbgs upon completion of
drilling.
2) 20mm monitoring well was
installed upon completion.
11
SS
50/
initial
25mm
68
Water Level Readings:
Date
June 18/14
W.L. Depth (m)
2.2
GRAPH
NOTES
GROUNDWATER ELEVATIONS
Shallow/ Single Installation
Deep/Dual Installation
3,
3 : Numbers refer
to Sensitivity
=3%
Strain at Failure
5 42 39 14
LOG OF BOREHOLE BH14-2
1 OF 1
PROJECT: Geotechnical Investigation-Proposed Replacement of Three Culverts
DRILLING DATA
CLIENT: TMIG
Method: Solid Stem Auger
PROJECT LOCATION: Krosno Creek - Various Streets, Pickering, ON
Diameter: 150mm
REF. NO.: 10000247-110
DATUM: Geodetic
Date: May/13/2014
Drawing No.: 6
10
2
SS
10
3
SS
9
4
SS
10
5
SS
2
40
60
80
NATURAL
PLASTIC
MOISTURE
LIMIT
CONTENT
100
UNCONFINED
QUICK TRIAXIAL
20
40
60
w
wP
SHEAR STRENGTH (kPa)
FIELD VANE
& Sensitivity
LAB VANE
80
100
LIQUID
LIMIT
wL
WATER CONTENT (%)
10
20
POCKET PEN.
(Cu) (kPa)
SS
20
ELEVATION
1A
1B
GROUND WATER
CONDITIONS
"N" BLOWS
0.3 m
TOPSOIL: 175mm
FILL: clayey silt to silty clay, trace
topsoil, brown, moist, stiff.
TYPE
80.4
0.0
80.2
0.2
DESCRIPTION
NUMBER
(m)
ELEV
DEPTH
DYNAMIC CONE PENETRATION
RESISTANCE PLOT
SAMPLES
STRATA PLOT
SOIL PROFILE
30
NATURAL UNIT WT
3
(Mg/m )
BH LOCATION: Morden Lane
REMARKS
AND
GRAIN SIZE
DISTRIBUTION
(%)
GR SA SI CL
80
79
78
77.7
2.7
SILTY CLAY: trace sand, brown,
very moist to wet, firm to stiff.
----------------------grey below 3.1m
50
77
2.0
ra
ft
VANE
76
6
74.8
5.6
2
SS
2.6
VANE
75
SILTY SAND TILL: trace to some
clay, trace gravel, grey, moist,
compact to very dense
7
SS
74
15
73
SS
64
D
8
trace shale fragments below 9.1m
9
SS
72
50/
initial
50mm
71
70
SPL SOIL LOG 10000247 LOGS.GPJ SPL.GDT 4/7/14
69.5
11.0
68.1
12.3
10
SS
SHALE BEDROCK: weathered,
blackish grey.
END OF THE BOREHOLE
Notes:
1) Borehole open and water level
3.7mbgs upon completion of drilling.
69
11
SS
50/
initial
75mm
GRAPH
NOTES
GROUNDWATER ELEVATIONS
Shallow/ Single Installation
65/
150mm
Deep/Dual Installation
3,
3 : Numbers refer
to Sensitivity
=3%
Strain at Failure
0
2 64 34
LOG OF BOREHOLE BH14-3
1 OF 1
PROJECT: Geotechnical Investigation-Proposed Replacement of Three Culverts
DRILLING DATA
CLIENT: TMIG
Method: Solid Stem Auger
PROJECT LOCATION: Krosno Creek - Various Streets, Pickering, ON
Diameter: 150mm
REF. NO.: 10000247-110
DATUM: Geodetic
Date: May/13/2014
Drawing No.: 7
76.0
2.8
-----------------------------------silty sand pockets at 2.3m
SILTY CLAY: trace sand, brown
mottled with grey, moist, firm to stiff.
12
2
SS
18
3
SS
13
4
SS
10
40
60
80
NATURAL
PLASTIC
MOISTURE
LIMIT
CONTENT
100
UNCONFINED
QUICK TRIAXIAL
20
40
60
w
wP
SHEAR STRENGTH (kPa)
FIELD VANE
& Sensitivity
LAB VANE
80
100
wL
WATER CONTENT (%)
10
20
30
REMARKS
AND
GRAIN SIZE
DISTRIBUTION
(%)
GR SA SI CL
78
77
76
5
SS
12
2.0
75
ra
ft
VANE
-------------------------silty seams at 4.6m
LIQUID
LIMIT
POCKET PEN.
(Cu) (kPa)
SS
20
ELEVATION
1
GROUND WATER
CONDITIONS
"N" BLOWS
0.3 m
77.3
1.5
TOPSOIL: 200mm
FILL: sandy silt, some clay, trace to
some topsoil, dark brown, moist,
compact.
------------------------------------------------trace topsoil with silty clay pockets at
0.8m
FILL: silty clay, trace organics, dark
brown to dark grey, moist, stiff.
TYPE
78.8
0.0
78.6
0.2
DESCRIPTION
NUMBER
(m)
ELEV
DEPTH
DYNAMIC CONE PENETRATION
RESISTANCE PLOT
SAMPLES
STRATA PLOT
SOIL PROFILE
NATURAL UNIT WT
3
(Mg/m )
BH LOCATION: Reytan Boulevard
6
SS
74
3
1 58 41
73
SH
72
VANE
70.3
8.5
GRAVELLY SAND: some silt, trace
clay, grey, wet, very loose to compact
7
SS
71
3
D
71.2
7.6
SILTY SAND TILL: some gravel,
trace clay, grey, wet, dense.
8
SS
3.0
30
26 52 17 5
70
69
SPL SOIL LOG 10000247 LOGS.GPJ SPL.GDT 4/7/14
68
67
66.6
66.5
12.2
12.3
SHALE BEDROCK: weathered,
greyish black.
END OF THE BOREHOLE
Notes:
1) Borehole open and water level
2.7mbgs upon completion of drilling.
SS
50/
initial
25mm
GRAPH
NOTES
GROUNDWATER ELEVATIONS
Shallow/ Single Installation
9
Deep/Dual Installation
3,
3 : Numbers refer
to Sensitivity
=3%
Strain at Failure
LOG OF BOREHOLE BH14-4
1 OF 1
PROJECT: Geotechnical Investigation-Proposed Replacement of Three Culverts
DRILLING DATA
CLIENT: TMIG
Method: Solid Stem Auger
PROJECT LOCATION: Krosno Creek - Various Streets, Pickering, ON
Diameter: 150mm
REF. NO.: 10000247-110
DATUM: Geodetic
Date: May/12/2014
Drawing No.: 8
SS
4
Cement
2
SS
12
78
3
SS
9
4
SS
12
5
SS
8
6
SS
5
------------------------------------150mm layer of sand
77.0
2.0
SILTY CLAY: trace sand,
occasional wet silt seams, brown,
moist, firm to stiff.
ELEVATION
1
40
60
80
100
FIELD VANE
& Sensitivity
LAB VANE
80
100
LIQUID
LIMIT
w
wP
SHEAR STRENGTH (kPa)
UNCONFINED
QUICK TRIAXIAL
20
40
60
NATURAL
PLASTIC
MOISTURE
LIMIT
CONTENT
wL
WATER CONTENT (%)
10
20
POCKET PEN.
(Cu) (kPa)
GROUND WATER
CONDITIONS
"N" BLOWS
0.3 m
TOPSOIL: 170mm
FILL: clayey silt, trace sand, trace
organics, brown, moist, firm to stiff.
TYPE
79.0
0.0
78.8
0.2
DESCRIPTION
20
NUMBER
(m)
ELEV
DEPTH
DYNAMIC CONE PENETRATION
RESISTANCE PLOT
SAMPLES
STRATA PLOT
SOIL PROFILE
30
77
75
76
50
75
ra
ft
Bentonite
7
SS
3
74
2.4
VANE
73
8
SS
2
72
3
71
D
SS
Sand
VANE
69.6
9.4
SPL SOIL LOG 10000247 LOGS.GPJ SPL.GDT 4/7/14
68.3
10.7
66.7
12.3
SAND: trace to some silt, trace
gravel, grey, wet, compact
SILTY SAND TILL: trace to some
clay, trace gravel, grey, wet, very
dense.
10
SS
2.0
70
23
69
Screen
11
SS
57
12
SS
50/
initial
75mm
68
Sand
67
some clay, moist below 12.2m
END OF THE BOREHOLE
Notes:
1) Borehole cave in 11.6mbgs and
water level 4.3mbgs upon completion
of drilling.
2) 20mm monitoring well was
installed upon completion.
Water Level Readings:
Date
June 18/14
W.L. Depth (m)
1.3
GRAPH
NOTES
GROUNDWATER ELEVATIONS
Shallow/ Single Installation
Deep/Dual Installation
3,
3 : Numbers refer
to Sensitivity
=3%
Strain at Failure
REMARKS
AND
GRAIN SIZE
DISTRIBUTION
(%)
GR SA SI CL
W. L. 77.7 m
Jun 18, 2014
grey below 3.8m
NATURAL UNIT WT
3
(Mg/m )
BH LOCATION: Reytan Boulevard
LOG OF BOREHOLE BH14-5
1 OF 1
PROJECT: Geotechnical Investigation-Proposed Replacement of Three Culverts
DRILLING DATA
CLIENT: TMIG
Method: Solid Stem Auger
PROJECT LOCATION: Krosno Creek - Various Streets, Pickering, ON
Diameter: 150mm
REF. NO.: 10000247-110
DATUM: Geodetic
Date: May/07/2014
Drawing No.: 9
9
2
SS
7
3
SS
6
4
SS
10
5
SS
5
6
SS
3
40
60
80
100
FIELD VANE
& Sensitivity
LAB VANE
80
100
LIQUID
LIMIT
w
wP
SHEAR STRENGTH (kPa)
UNCONFINED
QUICK TRIAXIAL
20
40
60
NATURAL
PLASTIC
MOISTURE
LIMIT
CONTENT
wL
WATER CONTENT (%)
10
20
30
POCKET PEN.
(Cu) (kPa)
SS
20
ELEVATION
1A
GROUND WATER
CONDITIONS
"N" BLOWS
0.3 m
TOPSOIL: 100mm
FILL: clayey silt to silty clay, trace
topsoil, trace gravel, brown, moist,
firm to stiff.
---------------------------------------------75mm gravelly sand layer at 0.5m
TYPE
78.2
0.0
78.1
0.1
DESCRIPTION
NUMBER
(m)
ELEV
DEPTH
DYNAMIC CONE PENETRATION
RESISTANCE PLOT
SAMPLES
STRATA PLOT
SOIL PROFILE
NATURAL UNIT WT
3
(Mg/m )
BH LOCATION: Alyssum Street
REMARKS
AND
GRAIN SIZE
DISTRIBUTION
(%)
GR SA SI CL
78
Concrete
1B
7777.1 m
W. L.
Jun 18, 2014
76
75.6
2.6
CLAYEY SILT TO SILTY CLAY:
trace sand, brownish grey, very
moist, firm to stiff
0
74
ra
ft
---------------wet at 3.8m
75
Holeplug
73
SH
72
7
SS
2
71
SS
3
D
8
70
----------------------------------------25mm sandy silt layer at 8.2m
69.1
9.1
SILTY SAND: trace clay, trace
gravel, grey, wet, loose
9
SS
Sand
69
6
68
SPL SOIL LOG 10000247 LOGS.GPJ SPL.GDT 4/7/14
67.5
10.7
SILTY SAND TILL: trace to some
clay, trace gravel, trace shale
fragment, grey, moist, very dense.
Screen
10
SS
66
67
66
11
65.4
12.8
SS
Sand
60
END OF THE BOREHOLE
Notes:
1) Borehole open and water level
3.7mbgs upon completion of drilling.
2) 20mm monitoring well was
installed upon completion.
Water Level Readings:
Date
June 18/14
W.L. Depth (m)
1.1
GRAPH
NOTES
GROUNDWATER ELEVATIONS
Shallow/ Single Installation
Deep/Dual Installation
3,
3 : Numbers refer
to Sensitivity
=3%
Strain at Failure
2 75 23
LOG OF BOREHOLE BH14-6
1 OF 1
PROJECT: Geotechnical Investigation-Proposed Replacement of Three Culverts
DRILLING DATA
CLIENT: TMIG
Method: Solid Stem Auger
PROJECT LOCATION: Krosno Creek - Various Streets, Pickering, ON
Diameter: 150mm
REF. NO.: 10000247-110
DATUM: Geodetic
Date: May/12/2014
Drawing No.: 10
4
2
SS
9
40
60
80
100
FIELD VANE
& Sensitivity
LAB VANE
80
100
LIQUID
LIMIT
w
wP
SHEAR STRENGTH (kPa)
UNCONFINED
QUICK TRIAXIAL
20
40
60
NATURAL
PLASTIC
MOISTURE
LIMIT
CONTENT
wL
WATER CONTENT (%)
10
20
30
75.7
2.6
SS
14
4
SS
15
78
5
SS
11
76
SILTY CLAY: trace sand, brown,
moist, firm to stiff
75
2.0
VANE
ra
ft
74
grey below 4.6m
6
SS
2
73
7
SS
72
2
71
68.8
9.5
SS
2
D
8
----------------------------gravelly sand at 9.1m
SILTY SAND: trace gravel, trace
clay, grey, wet, very dense.
9
SS
70
69
2
68
SPL SOIL LOG 10000247 LOGS.GPJ SPL.GDT 4/7/14
67.5
10.8
67.2
11.1
SILTY SAND TILL: trace to some
clay, trace gravel, trace shale
fragments, grey, moist, very dense.
Notes:
1) Borehole open and water level
4.3mbgs upon completion of drilling.
GRAPH
NOTES
GROUNDWATER ELEVATIONS
Shallow/ Single Installation
10A SS
95/
10B
225mm
Deep/Dual Installation
3,
3 : Numbers refer
to Sensitivity
=3%
Strain at Failure
REMARKS
AND
GRAIN SIZE
DISTRIBUTION
(%)
GR SA SI CL
77
3
POCKET PEN.
(Cu) (kPa)
SS
20
ELEVATION
1
GROUND WATER
CONDITIONS
"N" BLOWS
0.3 m
TOPSOIL: 180mm
FILL: clayey silt to silty clay, trace
topsoil, trace sand, brown, moist, firm
to stiff
TYPE
78.3
0.0
78.1
0.2
DESCRIPTION
NUMBER
(m)
ELEV
DEPTH
DYNAMIC CONE PENETRATION
RESISTANCE PLOT
SAMPLES
STRATA PLOT
SOIL PROFILE
NATURAL UNIT WT
3
(Mg/m )
BH LOCATION: Alyssum Street
47
PERCENT PASSING
0
0.001
10
20
30
40
50
60
70
80
90
100
1
AND
SILT
0.01
GRAIN SIZE IN MICROMETERS
3
5
10
CLAY
30
50
#100
0.1
#50
Medium
Coarse
1
GRAIN SIZE DISTRIBUTION
GRAIN SIZE (MM)
tf
SIEVE DESIGNATION (Imperial)
#4
#16
SAND
a
r
D
75
#200
Fine
UNIFIED SOIL CLASSIFICATION SYSTEM
Date :
Project No.
Figure No:
10
June 20, 2014
10000247
11
BH 14-5 SS6
BH 14-3 SS8T
BH 14-1 SS7
BH 14-3 SS6
1"
Coarse
BH 14-2 SS5
BH 14-1 SS5
¾"
GRAVEL
3/8" ½"
Fine
100
Project: 10000247‐110 Appendix A General Comments – Bedrock in Toronto Area The bedrock that makes spread footings or caissons a popular choice for high‐rise foundation support is a shale or shale limestone composition. The highest member, the Queenston Formation, is generally found west of Toronto, while the Georgian Bay Formation underlies most of Metro Toronto, with the Collingwood Formation east of Toronto. The Queenston is, relatively speaking, the weaker of the three formations that are likely to support caissons or footings. The Georgian Bay as well as the Queenston and Collingwood Formation are of Middle Ordovician Age. It is defined as the rock unit that overlies the bluish grey shales of the Collingwood Formation and is in turn overlain by the red shale of the Queenston Formation. The Georgian Bay Formation consists of bluish and grey shale with interbeds of sandstone, limestone and dolostone. Towards the west where the Georgian Bay formation underlies the Queenston Formation, the limestone content increases significantly and limestone and/or sandstone may comprise as much as 70 to 90 percent of the bedrock. The hard layers are usually less than about 100 to 150 mm thick but some layers are much thicker. The thicker layers have been observed to be as much as 750 to 900 mm at some sites. The layers are actually lenses and they can vary significantly in thickness over short distances. ra
ft
The upper portion of the bedrock is commonly weathered for a depth of 600 to 1000 mm and within this weathered zone hard limestone layers or lenses are common. These hard limestone layers can result in contractual problems for augers, and can provide misleading bedrock elevations. Where the weathering is more extensive a shale till layer may be found above the bedrock. In the sound bedrock, the limestone, sandstone, dolostone is hard to very hard. D
Stress relief features such as folds and faults are common in the bedrock. In these features, the rock is heavily fractured and sheared, and contains layers of shale rubble and clay. Weathering is much deeper than the surrounding rock in these features and often there is a lateral migration of the stress relief features resulting in sound unweathered bedrock overlying fractured and weather bedrock. The stress relief features are usually in the order of 4 to 6 m wide, but the depth can vary from 4 to 5 m to in excess of 10 m. These features occur randomly. The bedrock contains significant high locked in horizontal stresses. These stresses can impose significant loads on tunnel walls but the slower rate of construction for basements allows for a relaxation of these stresses and they are not normally a problem for basement construction. Groundwater seepage below the top 1000 mm is generally small, however, at several locations in Toronto and Mississauga large quantities have been encountered. Bedding joints in the bedrock are very close‐to‐close, smooth planar in the shale and rough planar in the limestone. Significant vertical jointing is common. Where the bedrock was cored, a detailed description of the rock core is appended to the borehole log. Design features related to the bedrock are discussed in other sections of this report, and these general comments must be considered with these comments. Methane gas exists in the bedrock, normally below the top 1000 mm and more concentrated with depth. Appropriate care and monitoring is essential in all confined bedrock excavations, particularly caissons and tunnels.