highway 6 – cortiana bridge detailed geotechnical … · considering the construction of a new...
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November 22, 2019 File: 23783 Ministry of Transportation and Infrastructure 310 Ward Street, 4th Floor Nelson, BC V1L 5S4 Attention: Brad Panton, P.Eng.
HIGHWAY 6 – CORTIANA BRIDGE DETAILED GEOTECHNICAL DESIGN RECOMMENDATIONS
Dear Brad:
We have been retained to provide geotechnical engineering services for the design of a new bridge (or culvert) over Cortiana Creek on Hwy 6 near Cherryville, BC. This report provides geotechnical recommendations for detailed design based on previous investigations conducted by the ministry (MoTI)
This work has been carried out under our existing ‘as and when’ Contract No. 860CS1396 and 862CS1490.
1. BACKGROUND
We understand that the existing culverts were overwhelmed in the Spring of 2018 and MoTI is considering the construction of a new bridge to provide additional flow capacity at the site. The selected concept for the bridge is a single span bridge with spread footings on bedrock.
MoTI originally retained Sea to Sky drilling to collect preliminary subsurface information at the site. We have been provided with the soil and rock samples and the field logs prepared by the drillers. We attended a team site reconnaissance meeting with representatives from MoTI, Allnorth Engineering (structural designer) and Northwest Hydraulic Consultants (NHC) to familiarize ourselves with the project and interface with the team. We also carried out a bedrock probing investigation to check the depth to bedrock along the proposed bridge and retaining wall foundations
2. DRILL PROBING INVESTIGATION
The results of the Sea to Sky Drilling investigation indicated a generally shallow depth to bedrock across the site. However, the spread footing design depends on consistent rock elevation and additional bedrock surface information was recommended to reduce construction risk. Bedrock probing using a hydraulic drill and blast rig was determined to be the most efficient method to get this information.
2302, 4464 Markham Street, Victoria, BC V8Z 7X8 T: 250 727 2201 F: 250 727 3710 thurber.ca
Client: BC Ministry of Transportation and Infrastructure Date: November 22, 2019 File No.: 23783 Page 2 of 8 E-File: 20191122_Detailed Geotechnical Design report_Cortiana Bridge_23783.docx
In accordance with our ground disturbance protocols, we notified BC One Call to identify nearby buried and/or overhead utilities at each proposed probe hole location. Private Eye Utility Locating of Vernon, BC was also contracted to scan the area for underground utilities prior to drilling.
Twenty probe holes (PH19-1 to PH19-20) were drilled on March 27th and 28th, 2019 using a track mounted hydraulic drill and blast rig operated by Jocks Drill and Blasting Ltd of Vernon, BC. This method of drilling does not allow for sampling of the soils or bedrock; the comments of the driller and the drill action alone are used to interpret when bedrock is encountered. The holes are generally advanced at least 1.0 m into inferred rock to confirm its presence. The accuracy of bedrock depths using this method of drilling is typically about 0.3 m, however the results are occasionally unreliable if very steeply dipping bedrock, fractured or weathered bedrock or large boulders are encountered. Probe hole PH19-16 was terminated at 1.82 m depth due to possible bedding sand in cuttings indicating a potential utility or culvert installation. Probe hole PH19-5 did not encounter bedrock and was terminated at 10.97 m depth due to hole collapse of the overburden material resulting in the drill bit and rod couplings continually becoming jammed. Additional probe holes (PH19-19 and PH19-20) were drilled on either side of PH19-5 to provide additional information. The probe holes were generally drilled at the previously marked and surveyed locations, though several were relocated due to the location of underground utilities. The locations of the probe holes are shown on the attached Drawing No. 23873-2, and the probe hole coordinates are presented in Table 3.1 in section 3 of this report. All probe holes were backfilled with local sand and gravel and bentonite seals as required by the BC Groundwater Protection Regulation. Probe holes located within the road surface were reinstated using cold patch asphalt.
3. SITE CONDITIONS
We attended the site on September 19th, 2018 to carry out a site reconnaissance and meet with the project team. While on site it was observed that the existing culverts are constructed through a fill embankment that was built with granular fill (See Photo 1 in Appendix A). The existing rip-rap is variable in size and is generally courser on the downstream side of the highway (see Photos 2 and 3 in Appendix A). A sink hole in the shoulder was observed and is likely due to material migration within the embankment (See Photo 4 in Appendix A). This is likely due to poor grading of the existing embankment fills and significant water flows during flooding.
The existing embankment slopes are slightly steeper than 1.5H:1V and up to about 4 m high. No signs of slope instability were observed.
We were provided with the field logs, and samples (rock and soil) collected by Sea to Sky Drilling Ltd. (STS) and have prepared test hole logs based on this information and our laboratory testing. The test hole locations were surveyed by BCMoTI and provided to us in AutoCAD format. The attached Drawing 23763-1 in Appendix B shows the drill hole locations.
Client: BC Ministry of Transportation and Infrastructure Date: November 22, 2019 File No.: 23783 Page 3 of 8 E-File: 20191122_Detailed Geotechnical Design report_Cortiana Bridge_23783.docx
The compiled test hole logs are presented in Appendix C. We were not on site at the time of drilling and have not provided interpretation of the field observations on the logs.
The results of the drilling investigation indicate that bedrock is generally located between about 3 m and 6 m below the existing ground surface at the test hole locations except PH-16 and PH-19 as discussed above. The fill and native granular deposits are loose with SPT blow counts of less than 10. The bedrock core is a slightly weathered to fresh, strong, porphyritic Granite and is considered competent.
Table 3.1 – Inferred Ground Conditions
Probe Hole
Depth of Overburden (m)
Depth of "Weathered Rock"
(m)
Bedrock to Termination (m)
Northing
Easting
PH-1 0 - 3.65 3.65 - 5.48 5.48 - 7.31 542114.3 403541.6 PH-2 0 - 3.35 3.35 - 5.48 5.48 - 7.01 542108.9 403544.2 PH-3 0 - 3.35 3.35 - 4.41 4.41 - 6.70 542103.4 403546.8 PH-4 0 - 4.5 4.5 - 4.87 4.87 - 6.70 542098.0 403549.4 PH-5 0 - 10.97 N/A N/A 542092.7 403552.1 PH-6 0 - 4.5 4.5 - 4.87 4.87 - 6.70 542087.3 403554.8 PH-7 0 - 3.0 N/A 3.0 - 6.70 542081.2* 403558.2* PH-8 0 - 4.41 N/A 4.41 - 6.70 542079.5* 403565.3* PH-9 0 - 3.96 3.96 - 4.26 4.26 - 6.70 542076.2 403572.7
PH-10 0 - 3.65 N/A 3.65 - 6.40 542087.0 403567.6 PH-11 0 - 2.74 N/A 2.74 - 6.70 542059.6 403569.9 PH-12 0 - 4.5 N/A 4.5 - 6.70 542066.3 403572.7 PH-13 0 - 3.65 3.65 - 3.96 3.96 - 6.70 542064.4 403580.2 PH-14 0 - 3.65 3.65 - 4.87 4.87 - 5.48 542059.3 403583.4 PH-15 0 - 2.13 N/A 2.13 - 6.70 542055.3* 403586.0* PH-16 0 - 1.82 N/A N/A 542049.2* 403589.8* PH-17 0 - 2.13 N/A 2.13 - 6.70 542043.9* 403593.1* PH-18 0 - 1.82 N/A 1.82 - 6.70 542035.3* 403598.6* PH-19 0 - 5.63 N/A 5.63 - 8.22 542095.3* 403550.8* PH-20 0 - 8.22 N/A 8.22 - 10.21 542090.6* 403553.1*
*Probe hole not drilled at surveyed location and coordinates are based on offsets measured by hand on site.
Client: BC Ministry of Transportation and Infrastructure Date: November 22, 2019 File No.: 23783 Page 4 of 8 E-File: 20191122_Detailed Geotechnical Design report_Cortiana Bridge_23783.docx
4. GEOTECHNICAL RECOMMENDATIONS
We have provided interim reports for the conceptual design and participated in the detailed design process. The recommendations presented below supersede any previous recommendations.
4.1 Geotechnical Design Criteria
The geotechnical design for the bridge is intended to follow MoTI Technical Circular T-04/17. The design references the following documents when required:
• MoTI technical circulars. • CSA S6-14 (Canadian Highway Bridge Design Code, CHBDC). • MoTI Supplement to CHBDC S6-14. • AASHTO “LFRD Bridge Design Specifications”, 7th Edition, 2014. • Publication No. FHWA-NHI-10-024 “Design and Construction of Mechanically Stabilized
Earth Walls and Reinforced Soil Slopes” November 2009. • Publication No. FHWA-NHI-14-007 “Soil Nail Walls Reference Manual” February 2015. • BC Supplement to TAC Geometric Design Guide, Figure 440.H. • MoTI Technical Bulletin GM02001 Rock Slope Design. • Oregon Department of Transportation (ODOT) - Rockfall Catchment Area Design Guide -
Final Report SPR-3(032), Metric Edition, 2001. • Ritchie (1963) Ritchie, A.M., 1963. The evaluation of rock fall and its control. Highway
Record. Vol 17. • AASHTO 1993 Guide for the Design of Pavement Structures or AASHTO (2004) ME
Pavement (Mechanistic Empirical Pavement Design Method Guide). The previously completed investigation is inferred to obtain a typical degree of understanding for the design criteria. We have assumed that MoTI considers this bridge to be a major route bridge and the short section of highway approaches to be typical consequence (i.e. a target Factor of Safety of 1.54 is required for embankments).
4.2 Site Seismicity and Liquefaction
A site-specific hazard calculation was obtained from the National Resources Canada on-line seismic hazard calculator for the project site. The peak ground acceleration for the 10% in 50 years (1:475) design level earthquake is 0.021 g, 5% in 50 years (1:975) is 0.034g, and the 2% in 50 years (1:2475) is 0.058 g.
The bridge will be founded directly on bedrock and the site class recommended for design is Site Class B.
The drilling investigation included very limited soil sampling and density testing; however, it is noted that the existing granular soils are in a loose condition. We carried out a Cyclic Stress Ratio analysis which indicates that the soils are unlikely to liquify during the 1 in 2475 earthquake;
Client: BC Ministry of Transportation and Infrastructure Date: November 22, 2019 File No.: 23783 Page 5 of 8 E-File: 20191122_Detailed Geotechnical Design report_Cortiana Bridge_23783.docx
however, this is based on limited data. Since the bridge is founded on bedrock it was not deemed necessary to carry out additional geotechnical investigation and assessment.
4.3 Dewatering
The site is located directly adjacent to Cortiana Creek and the soils beneath the highway are expected to be highly permeable. It is anticipated that the groundwater table will correlate strongly with the creek elevation and any excavation below the creek level is anticipated to encounter significant groundwater. Dewatering of the excavations may not be possible with sump and pump methods and it might be necessary to divert the creek during construction to reduce the flow of water into the excavations.
4.4 Spread Footing Design Parameters
It is considered possible to found the new bridge / culvert footings on the bedrock surface using spread footings, however, there is some risk that the bedrock surface may drop off in some areas and that excavation to this depth may require significant dewatering. The bedrock surface should be levelled to within 6H:1V and thoroughly cleaned to reveal a clean, intact bedrock surface free of loose debris or highly fractured rock. If the bedrock surface is not level across the footing it should be chipped into a series of steps and may also require dowels. Given the foundation preparation described above, the recommended ULS bearing capacity of the footing is 2 MPa. The SLS bearing conditions for the footing are not limiting.
For sliding resistance at the base of footings, the friction factor for CIP concrete on clean bedrock can be assumed to be 0.7.
4.5 Lateral Earth Pressures on Abutment Walls
The abutment walls should be backfilled with Bridge End Fill (BEF) material meeting the requirements for BEF in Section 202 of the Ministry of Transportation and Infrastructure’s 2016 Standard Specifications for Highway Construction. Where retaining walls will be constructed along the river to support the highway embankment, SGSB granular fill with is considered suitable for construction. It is assumed that the BEF and SGSB will be a sandy gravel or crushed rock product with at least 30% gravel size particles, and the following material parameters can be assumed:
• total unit weight, γ, of 21 kN/m3, • a friction angle, φ’, of 36 degrees
For static design, an at-rest earth pressure coefficient, Ko, of 0.41 should be used for design of the abutment walls. This assumes level ground at the top of wall and 50% wall friction.
For active earth pressure design, the active earth pressure coefficient is (Ka)h = 0.24 at bottom of triangular distribution.
Client: BC Ministry of Transportation and Infrastructure Date: November 22, 2019 File No.: 23783 Page 6 of 8 E-File: 20191122_Detailed Geotechnical Design report_Cortiana Bridge_23783.docx
For seismic design, we recommend using the following seismic earth pressure coefficients (see Table 4.1) and applied either at 1/3 or ½ of the wall height from the base (we recommend checking both points to determine the governing load case).
Table 4.1: Seismic Active Earth Pressure Coefficients Seismic Hazard (Kae)h
1:475 .25
1:975 .26
1:2475 .27 Maximum allowable passive earth pressure to resist bridge displacements (caused by seismic inertial loads combined with active earth pressure on opposite abutment) can be calculated as per the Canadian Highway Bridge Design Code (CAN-CSA S6-14 Commentary, Page 135 “Near-Field Lateral Spring for Bridge Abutments”):
Kabut = Ki * w * [ h / 1.7 ] ; where Ki = 29 MN/m per m width w = width of the abutment h = height of the abutment in metres.
4.6 Dowels and Anchors
Two sets of groups of uplift anchors are required for the wall that spans over the anticipate area of the bedrock dropoff. We understand that the ULS loads are 1000 kN on individual anchors and 3000 kN for the group. Since the anchors are long and closely spaced (900 mm), each group of anchors is anticipated to share the same cone of rock. We understand that the anchors will consist of 46 mm (1035 MPa) DCP threadbar (PTI Class 1 Corrosion Protection). They should be installed in minimum 114 mm diameter holes with a free stressing length (bond breaker) of 3.0 m long (2 m in rock) and a minimum bond length of 4 m. The minimum total anchor length in rock is 6.0 m. For the shear dowels, it is assumed that the rock strength will generally exceed the strength of the concrete used for the wall construction; however, this assumes that all weathered and weaker rock is removed from the base of the footing. The minimum recommended length for shear dowels is 1 m into rock into 75 mm diameter holes. It is likely that the dropoff of the bedrock surface will be different than the surface shown on the drawings. Additional drop-offs and variations of the bedrock surface may also be encountered during construction. The design is based on our current interpretation of the bedrock surface and is considered reasonable for design; however, it should be noted as a risk item for construction. We also understand that 30M stainless steel dowels are required for the CIP concrete walls with a ULS uplift load of about 180 kN each. The dowels will be spaced at 1.0 m centres. We
Client: BC Ministry of Transportation and Infrastructure Date: November 22, 2019 File No.: 23783 Page 7 of 8 E-File: 20191122_Detailed Geotechnical Design report_Cortiana Bridge_23783.docx
recommend that the dowels be installed in minimum 75 mm diameter holes at least 2.0 m into intact bedrock. The dowels should be installed using at least two centralizers to maintain its position in the drilled hole during grouting.
4.7 Fill Embankments
We understand that widening of the existing embankment may be completed to shift the alignment, widen the existing shoulders and support the approach barriers. Since the creek runs beside the embankment, it will likely be necessary to protect the embankment from erosion using rip-rap (to be determined by others). The existing embankments are anticipated to be susceptible to internal erosion, and the new embankments require graded filters to reduce the likelihood of material migration through the fills. We understand that NHC has provided the graded filter designs for the project.
It is recommended that earth embankment fill be constructed at a maximum slope angle of 2H:1V. If rock fill is proposed to be used, the maximum recommended slope angle is 1.5H:1V. General fill construction should be carried out in accordance with Sections 201.36 and 201.37 of the BC MoTI 2016 Standard Specifications for Highway Construction.
Once the design subgrade elevation is exposed, the granular fill surface should be compacted with at least 4 passes of a minimum 10 tonne vibratory drum roller. A loaded tandem axle dump truck should then be used to proof-roll the prepared subgrade to check for possible weak subgrade areas. Any weak areas identified during proof-rolling should be sub-excavated and replaced with compacted granular fill that meets the MoTI BEF specification. All fill should be placed and compacted in accordance with Standard Specification Sections 201.37 and 202.25.
All fill slopes should be keyed into the existing embankment slope by excavating horizontal benches into the existing slope as per Standard Specification Sections 201.36 and 201.37.
4.8 Pavement Design
We have carried out a pavement design analysis using the methodology outlined in the 1993 AASHTO “Guide for the Design of Pavement Structure” and a range of traffic loading inputs (ESALs).
We carried out a simple ESAL calculation with the following assumptions: • 20-year design life • 1,300 AADT (50% in each direction) • 2% growth • 5% trucks • 1.7 truck factor
The resulting prediction is about 500,000 ESAL’s.
STATEMENT OF LIMITATIONS AND CONDITIONS
1. STANDARD OF CARE
This Report has been prepared in accordance with generally accepted engineering or environmental consulting practices in the applicable jurisdiction. No other warranty, expressed or implied, is intended or made.
2. COMPLETE REPORT
All documents, records, data and files, whether electronic or otherwise, generated as part of this assignment are a part of the Report, which is of a summary nature and is not intended to stand alone without reference to the instructions given to Thurber by the Client, communications between Thurber and the Client, and any other reports, proposals or documents prepared by Thurber for the Client relative to the specific site described herein, all of which together constitute the Report.
IN ORDER TO PROPERLY UNDERSTAND THE SUGGESTIONS, RECOMMENDATIONS AND OPINIONS EXPRESSED HEREIN, REFERENCE MUST BE MADE TO THE WHOLE OF THE REPORT. THURBER IS NOT RESPONSIBLE FOR USE BY ANY PARTY OF PORTIONS OF THE REPORT WITHOUT REFERENCE TO THE WHOLE REPORT.
3. BASIS OF REPORT
The Report has been prepared for the specific site, development, design objectives and purposes that were described to Thurber by the Client. The applicability and reliability of any of the findings, recommendations, suggestions, or opinions expressed in the Report, subject to the limitations provided herein, are only valid to the extent that the Report expressly addresses proposed development, design objectives and purposes, and then only to the extent that there has been no material alteration to or variation from any of the said descriptions provided to Thurber, unless Thurber is specifically requested by the Client to review and revise the Report in light of such alteration or variation.
4. USE OF THE REPORT
The information and opinions expressed in the Report, or any document forming part of the Report, are for the sole benefit of the Client. NO OTHER PARTY MAY USE OR RELY UPON THE REPORT OR ANY PORTION THEREOF WITHOUT THURBER’S WRITTEN CONSENT AND SUCH USE SHALL BE ON SUCH TERMS AND CONDITIONS AS THURBER MAY EXPRESSLY APPROVE. Ownership in and copyright for the contents of the Report belong to Thurber. Any use which a third party makes of the Report, is the sole responsibility of such third party. Thurber accepts no responsibility whatsoever for damages suffered by any third party resulting from use of the Report without Thurber’s express written permission.
5. INTERPRETATION OF THE REPORT
a) Nature and Exactness of Soil and Contaminant Description: Classification and identification of soils, rocks, geological units, contaminant materials and quantities have been based on investigations performed in accordance with the standards set out in Paragraph 1. Classification and identification of these factors are judgmental in nature. Comprehensive sampling and testing programs implemented with the appropriate equipment by experienced personnel may fail to locate some conditions. All investigations utilizing the standards of Paragraph 1 will involve an inherent risk that some conditions will not be detected and all documents or records summarizing such investigations will be based on assumptions of what exists between the actual points sampled. Actual conditions may vary significantly between the points investigated and the Client and all other persons making use of such documents or records with our express written consent should be aware of this risk and the Report is delivered subject to the express condition that such risk is accepted by the Client and such other persons. Some conditions are subject to change over time and those making use of the Report should be aware of this possibility and understand that the Report only presents the conditions at the sampled points at the time of sampling. If special concerns exist, or the Client has special considerations or requirements, the Client should disclose them so that additional or special investigations may be undertaken which would not otherwise be within the scope of investigations made for the purposes of the Report.
b) Reliance on Provided Information: The evaluation and conclusions contained in the Report have been prepared on the basis of conditions in evidence at the time of site inspections and on the basis of information provided to Thurber. Thurber has relied in good faith upon representations, information and instructions provided by the Client and others concerning the site. Accordingly, Thurber does not accept responsibility for any deficiency, misstatement or inaccuracy contained in the Report as a result of misstatements, omissions, misrepresentations, or fraudulent acts of the Client or other persons providing information relied on by Thurber. Thurber is entitled to rely on such representations, information and instructions and is not required to carry out investigations to determine the truth or accuracy of such representations, information and instructions.
c) Design Services: The Report may form part of design and construction documents for information purposes even though it may have been issued prior to final design being completed. Thurber should be retained to review final design, project plans and related documents prior to construction to confirm that they are consistent with the intent of the Report. Any differences that may exist between the Report’s recommendations and the final design detailed in the contract documents should be reported to Thurber immediately so that Thurber can address potential conflicts.
d) Construction Services: During construction Thurber should be retained to provide field reviews. Field reviews consist of performing sufficient and timely observations of encountered conditions in order to confirm and document that the site conditions do not materially differ from those interpreted conditions considered in the preparation of the report. Adequate field reviews are necessary for Thurber to provide letters of assurance, in accordance with the requirements of many regulatory authorities.
6. RELEASE OF POLLUTANTS OR HAZARDOUS SUBSTANCES
Geotechnical engineering and environmental consulting projects often have the potential to encounter pollutants or hazardous substances and the potential to cause the escape, release or dispersal of those substances. Thurber shall have no liability to the Client under any circumstances, for the escape, release or dispersal of pollutants or hazardous substances, unless such pollutants or hazardous substances have been specifically and accurately identified to Thurber by the Client prior to the commencement of Thurber’s professional services.
7. INDEPENDENT JUDGEMENTS OF CLIENT
The information, interpretations and conclusions in the Report are based on Thurber’s interpretation of conditions revealed through limited investigation conducted within a defined scope of services. Thurber does not accept responsibility for independent conclusions, interpretations, interpolations and/or decisions of the Client, or others who may come into possession of the Report, or any part thereof, which may be based on information contained in the Report. This restriction of liability includes but is not limited to decisions made to develop, purchase or sell land.
HKH/LG_Dec 2014
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Client: BCMoTI Date: October 5, 2018 File No.: 23783 Photo page 1 of 2 E-File: Cortiana Photos_23783.docx
PHOTO 1: View of upstream side of culverts (inlet).
PHOTO 2: View of Cortiana Creek looking upstream.
Client: BCMoTI Date: October 5, 2018 File No.: 23783 Photo page 2 of 2 E-File: Cortiana Photos_23783.docx
PHOTO 3: View of Cortiana Creek looking downstream.
PHOTO 4: View of sink hole in shoulder of Hwy 6 on Upstream
side of embankment.
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1139
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1138
11391137
1137
1140
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1
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10+160
10+140
10+120
10+180
TH-A
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TH-C
This copyrighted draw
ing form
s part of a T
hurber report and its use is subject to T
hurber's S
tatem
ent of Lim
itations and C
onditions
23783-C
AD
001.dw
gP
lotted: O
ctober 05, 2018
1. Test hole locations and digital base plans provided
by the Ministry of Transportation and Infrastructure.
2. Contour interval is 0.5 metre.
NOTES:
DWG. NO.PROJECT No. REV.DESIGNED DRAWN DATEAPPROVED SCALE
-
- 1237831:250OCTOBER 5, 2018
RRSWRW
NEAR CHERRYVILLE, B.C.GEOTECHNICAL INVESTIGATION
HIGHWAY 6; PROPOSED CORTIANA BRIDGE
TEST HOLE LOCATION PLAN
MINISTRY OF TRANSPORTATION AND INFRASTRUCTURE
15 m
SCALE 1:250
2.50 5 7.5 10 12.5
T
H
-
C
T
H
-
D
T
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-
A
T
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E
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1
9
-
1
P
H
1
9
-
2
P
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1
9
-
3
P
H
1
9
-
6
P
H
1
9
-
1
0
P
H
1
9
-
9
P
H
1
9
-
1
2
P
H
1
9
-
1
1
P
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1
9
-
1
3
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1
9
-
1
4
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1
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-
1
6
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-
5
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1
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B
This copyrighted draw
ing form
s part of a T
hurber report and its use is subject to T
hurber's S
tatem
ent of Lim
itations and C
onditions
23783-C
AD
002.dw
gP
lotted: A
pril 05, 2019
1. Depth to inferred bedrock using hydraulic rock drilling is based on the
action of the drill and the driller's comments. Refer to geotechinical report
for limitations of this drill method.
2. Probe hole locations and digital base plans provided on March 14, 2019,
by the Ministry of Transportation and Infrastructure.
3. PH19-7, -8, -15, -17, and -18 were moved slightly from original layout to
avoid services; PH19-19 and -20 were added during the investigation.
4. Contour interval is 0.5 metre.
NOTES:
DWG. NO.PROJECT No. REV.DESIGNED DRAWN DATEAPPROVED SCALE
-
- 2237831:300APRIL 5, 2019
RRSWRW
NEAR CHERRYVILLE, B.C.GEOTECHNICAL INVESTIGATION
HIGHWAY 6; PROPOSED CORTIANA BRIDGE
BEDROCK PROBING LOCATION PLAN
MINISTRY OF TRANSPORTATION AND INFRASTRUCTURE
0 4
SCALE 1:300
10 15 20m2 6 8
DRILLING SUMMARY
DEPTH TO INFERRED
WEATHERED BEDROCK (m)
DEPTH TO INFERRED
BEDROCK (m)
PH19-1
PH19-2
PH19-3
PH19-4
PH19-5
PH19-6
PH19-7
PH19-8
PH19-9
PH19-10
PH19-11
PH19-12
PH19-13
PH19-14
PH19-15
PH19-16
PH19-17
PH19-18
PH19-19
PH19-20
3.7
3.4
3.4
4.5
-
4.5
-
-
4.0
-
-
-
3.7
3.7
-
-
-
-
-
-
5.5
5.5
4.4
4.9
> 11.0
4.9
3.0
4.4
4.3
3.7
2.7
4.5
4.0
4.9
2.1
-
2.1
1.9
5.6
8.2
LEGEND:
2019 Probe Hole
PH19-7
TH-E
2018 Test Hole
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Symbol Soil Type
GW Well-graded gravels or gravel-sand mixtures, little or no fines
GP Poorly-graded gravels or gravel-sand mixtures, little or no fines
GM* Silty gravels, gravel-sand-silt mixtures
GC* Clayey gravels, gravel-sand-clay mixtures
SW* Well-graded sands or gravelly sands, little to no fines
SP Poorly-graded sands or gravelly sands, little or no fines
SM* Silty sands, sand-silt mixtures
SC* Clayey sands, sand-clay mixtures
MLInorganic silts and very fine sands, rock flour, silty or clayey fine
sands, or clayey silts with slight plasticity
CLInorganic clays of low to medium plasticity, gravelly clays, sandy clays,
silty clays, lean clays
OL Organic silts and organic silt-clays of low palsticity
MHInorganic silts, micaceous or diatomaceous fine sandy or silty soils,
elastic silts
CH Inorganic clays of high plasticity, fat clays
OH Organic clays of medium to high plasticity, organic silts
Pt Peat and other highly organic soils
TS Topsoil with roots, etc.
SB Rock fragments and cobbles, particle size 75mm to 300mm diameter
LB Boulders, particle size over 300mm in diameter
BCMOTI SOIL CLASSIFICATION
Major Divisions
Co
ars
e G
rain
ed
So
ils
Gra
vel and
Gra
velly
Soils
Sand a
nd
Sandy
Soils
Fin
e G
rain
ed
So
ils
Silt
s and
Cla
ys L
L<
50
Silt
s and
Cla
ys L
L>
50
Organic Soils
Topsoil
Cobbles
Boulders
*GP-GM ; GP-GC; SP-SM; SP-SC; 6-12% Passing #200 (0.075mm) Sieve
* GM1; GC1; SM1; SC1; 12-20% Passing #200 (0.075mm) Sieve
* GM2; GC2; SM2; SC2; 20-30% Passing #200 (0.075mm) Sieve
* GM3; GC3; SM3; SC3; 30-40% Passing #200 (0.075mm) Sieve
* GM4; GC4; SM4; SC4; 40-50% Passing #200 (0.075mm) Sieve
RU
DA
CE
OU
SA
RE
NA
CE
OU
S
LIM
ES
TO
NE
(undiff
ere
ntia
ted)
AR
GIL
LA
CE
OU
S o
r LU
TA
CE
OU
S
ROCK MATERIAL DESCRIPTION
Descriptions should follow the form “Colour, grain size, textural fabric, weathering, alteration, strength, type”. Example: Da rk bluish grey, fine-grained, crystalline, slightly weathered, moderately strong basalt.
COLOURShade SecondaryPrimarylight pinkish pinkdark reddish red
yellowish yellowbrownish brownolive olivegreenish greenbluish blue
whitegreyish grey
black
GRAIN SIZETerm Particle Retained on Equivalent
Size Sieve Size Soil Grade
Very coarse-grained >60 mm 2 inch Coarse gravel, cobbles, bouldersCoarse-grained 2 - 60 mm No. 8 GravelMedium-grained 60 microns - 2 mm No. 200 SandFine-grained 2 - 60 microns SiltVery fine-grained <2 microns Clay
Note: grains >60 microns are visible to the naked eye.
TEXTURE/ FABRIC
crystallinegranularglassy
WEATHERING / ALTERATIONTerm Description
Fresh No visible sign of rock material weathering.Faintly weathered Discoloration on major discontinuity surfaces.Slightly weathered Discoloration indicates weathering of rock material and discontinuity surfaces. All the rock material may be discolored by weathering and may be somewhat weaker than in its
fresh condition.Moderately weathered Less than half of the rock material is decomposed and/or disintegrated to a soil. Fresh or discoloured rock is present either as a continuous framework or as corestones.Highly weathered More than half the rock material is decomposed and/or disintegrated to a soil. Fresh or discoloured rock is present either as discontinuous framework or as corestones.Completely weathered All rock material is decomposed and/or disintegrated to soil. The original mass structure is still largely intact.Residual soil All rock material is converted to soil. The mass structure and material fabric are destroyed. Thhearen gise ain l avrogleu mc e, but the soil has not been significantly transported.
ROCK STRENGTHTerm Grade Unconfined compressive strength Field estimation of strength
(MPa) (psi)Extremely strong rock R6 >250 >36,000 Specimen can only be chipped with a geological hammer.Very strong rock R5 100 - 250 15,000 - 36,000 Specimen requires many blows of a geological hammer to fracture it.Strong rock R4 50 - 100 7,500 - 15,000 Specimen requires more than one blow of geological hammer to fracture it.Medium strong rock R3 25 - 50 3,500 - 7,500 Cannot be scraped or peeled with a pocket knife, specimen can be fractured with single firm blow of geological hammer.Weak rock R2 5 - 25 750 - 3,500 Can be peeled by a pocket knife with difficulty, shallow indentations made by firm blow with point of geological hammer.Very weak rock R1 1 - 5 150 - 750 Crumbles under firm blows with point of geological hammer, can be peeled by a pocket knife.Extremely weak rock R0 .25 - 1 35 - 150 Indented by thumbnail.Hard clay1 S6 >.50 >70 Indented with difficulty by thumbnail.Very stiff clay1 S5 0.25 - 0.50 35 - 70 Readily indented by thumbnail.Stiff clay1 S4 0.10 - 0.25 15 - 35 Readily indented by thumb but penetrated only with great effort.Firm clay1 S3 0.05 - 0.10 7 - 15 Can be penetrated several inches by thumb with moderate effort.Soft clay1 S2 0.025 - 0.05 4 - 7 Easily penetrated several inches by thumb.Very soft clay1 S1 <0.025 <4 Easily penetrated several inches by fist.
1These soil strengths are as recommended by ISRM but should only be used to describe highly weathered rock, residual soils or rock discontinuity filling; they do not correspond to ASTM D2488 consistencycriteria.
ROCK TYPE
Genetic group Detrital sedimentary Pyroclastic Chemicalorganic
Metamorphic Igneous
Usual Structure BEDDED BEDDED FOLIATED MASSIVE MASSIVE
COMPOSITION
Grainsize
(mm)
Grains of rock,quartz. feldspar
and minerals
At least 50% ofgrains are of
carbonate
At least 50% of grainsare of fine-grained
volcanic rock
Quartz, feldspars,micas, aciculardark minerals
Verycoarsegrained
Coarsegrained
60
2
Grains are of rockfragments
Rounded grains:CONGLOMERATE
Angular grains:BRECCIA
CALCI-RUDITE
Rounded grainsAGGLOMERATE
Angular grainsVOLCANICBRECCIA
MIGMATITE HORNFELS
SALINEROCKSHalite
AnhydriteGypsum
GNEISS MARBLE
Mediumgrained
0.06
0.002
SANDSTONE Grains aremainly mineral fragmentsQUARTZ SANDSTONE:
95% quartz, voidsempty or cemented
ARKOSE: 75% quartz,up to 25% feldspar: voids
empty or cementedARGILLACEOUS
SANDSTONE: 75%quartz, 15% + fine
detritalmaterial
CALC-ARENITE
TUFF
Alternate layersof granular andflakey minerals
SCHIST
PHYLLITE
GRANULITE
QUARTZITE
AMPHIBOLITE
Finegrained
Veryfine
grained
MUDSTONESHALE: fissile
mudstoneSILTSTONE: 50%
fine-grained particlesCLAYSTONE: 50%
very fine-grainedparticles
CALCAREOUSMUDSTONE
CALCI-SILTITE
CALCI-LUTITE
Fine-grained TUFF
Very fine-grainedTUFF
CHERT
FLINT
COAL
OTHERS
SLATE
MYLONITE
GLASSY
References: Geological Society Engineering Group Working Party (1977), The Description of Rock Masses For Engineering Purposes, Quaterly Journal of Engineering Geology, Vol. 10; Rock Chracterization Testing and Monitoring, ISRM Suggested Methods, E. Brown, Pergamon Press; Manual of Mineralogy, 20th Editi on, C. Klein and C. Hurlbut, Wiley; Canadian Foundation Engineering Manual, 2nd Edition, 1985, Canadian Geotechnical Society; Foundations on Rock, D. Wyllie, E & FN Spon.
ROCK MASS DESCRIPTION
Descriptions of rock mass should include detailed description of the discontinuities and the state of weathering and alteration. Discontinuity description should include type, number of sets, location, orientation(dip/dip direction), fracture spacing, separation of fracture surfaces, infilling, persistence (continuous length) and surface roughness and shape. Example: “Columnar jointed with vertical columns and one setof horizontal joints, spacing of vertical joints is very wide, spacing of horizontal joints wide, joints lengths are 3 to 5 m (10 to 16 ft) vertically and 0.5 to 1m (1.5 to 3 ft) horizontally; joint aperture is open and thefracture infilling is very soft clay. The vertical columnar joints are smooth, while the horizontal joints are very rough.”
TYPEJoint - break with no visible displacementFault - fracture with recognizable displacementCleavage planeBedding planeSchistocity planeWeakness zoneFissureTension crackFoliation
SPACINGPerpendicular distance between adjacentdiscontinuitiesExtremely wide >6 mVery wide 2 m - 6 mWide 600 - 2 mModerate 200 - 600 mmClose 60 - 200 mmVery close 20 - 60 mmExtremely close <20 mm
ORIENTATIONDip, dip direction and trend of lineationexpressed as degrees
PERSISTENCEModal trace length for each setVery low <1 mLow 1 - 3 mMedium 3 - 10 mHigh 10 - 20 mVery high >20 m
BLOCK SIZE
Term Block size
Very large >8 m3
Large 0.2 - 8 m3
Medium 0.008 - 0.2 m3
Small 0.0002 - 0.008 m3
Very small <0.0002 m3
Equivalent discontinuityspacings in blocky rock
Very wide to extremely wideWideModerateCloseLess than close
APERTURE<0.1 mm Very tight0.1 - 0.25 mm Tight “Closed” features0.25 - 0.5 mm Partly open0.5 - 2.5 mm Open2.5 - 10 mm Moderately wide “Gapped” features>10 mm Wide1 - 10 cm Very wide10 - 100 cm Extremely wide “Open” features>1 m Cavernous
FORMOverall shape of the discontinuity
PlanarUndulatingSteppedIrregular
ROUGHNESSPolished Shiny smooth and slippery in all directionsSlickensided Polished in one direction and showing evidence of significant movementSmooth Smooth to the touchSlightly rough Asperities on the fracture surfaces are visible and can be distinctly feltMedium rough Asperities are clearly visible and fracture surface feels abrasiveRough Large angular asperities can be seen and distantly feltVery rough Highly irregular jagged surfacesDefined ridges Supplemental - used with above termsSmall steps Supplemental - used with above terms
JRC - joint roughness coefficient0 - 22 - 4
4 - 1010 - 1212 - 1616 - 20
>20
Mapping Symbols
Joint dip and strike direction
Horizontal joint
Vertical joint and strike direction
Bedding dip and strike direction
Foliation dip and strike direction
Rock Mass Descriptive Terms
massive = few joints or very wide spacingblocky = approximately equidimensionaltabular = one dimension considerably smaller
than the other twocolumnar = one dimension considerably larger than
the other twoirregular = wide variations of block size and shapecrushed = heavily jointed to “sugar cube”
aperture = the perpendicular distance separatingthe adjacent rock walls of an opendiscontinuity
width = the perpendicular distance separatingthe adjacent rock walls of a filleddiscontinuity
Drill Core Descriptive Terms (all measurements on rockcore are taken along the centreline axis of the core )
recovery = summed length of all pieces ofrecovered core expressed as a % oflength drilled
frequency = number of natural discontinuitiesintersecting a length of core (expressedfor each metre of core unless otherwisedescribed)
RQD = Rock Quality Designation, a modifiedcore recovery percentage in which allthe pieces of sound core over 10 cmlong are counted as recovery and areexpressed as a percentage of the
length drilled
TYPICAL ROUGHNESS PROFILES JRC range
0 - 2
2 - 4
4 - 6
6 - 8
8 - 10
10 - 12
12 - 14
14 - 16
16 - 18
18 - 20
Scale
Start NQcoring at4.27mdepth.
GP
SP
BR
2.2m
3.5m
8.23m
1
2
17
Loose, wet, brown, sandy GRAVEL(probable FILL); poorly graded; gravel to75 mm diameter
Loose, wet, grey-brown, gravelly SAND;trace silt; gravel to 25 mm diameter
BEDROCK(see Rock Core logs)
End of Test Hole at 8.23 m depth.
Note 1: Logging carried out by Sea to SkyDrilling for MoTI. The field logs wereprovided to Thurber Engineering Ltd. fordrafting.
Note 2: Test Hole closure summary wasnot provided.
ELE
VA
TIO
N (
m)
1
2
3
4
5
6
7
8
9
LegendSample Type:
S-SplitSpoon
O-Odex(air rotary)
T-ShelbyTube
C-CoreA-Auger G-Grab V-Vane
1
2
3
4
5
6
7
8
9
Driller: Chad Brown
Drill Make/Model: Mobile B-53
CLA
SSIF
ICAT
ION
Location: Near Cherryville, B.C.
Date(s) Drilled: May 16, 2018
Drilling Method: Wash RotaryCoordinates Surveyed
Project: Cortiana Bridge
L#-Lab SampleW-Wash(mud return)
1138
1137
1136
1135
1134
1133
1132
1131
1130
Thurber Engineering Ltd. / Sea toSky Drilling
Prepared by:
Logged by: Reviewed by: WRW
SO
IL S
YM
BO
L
Drill Hole #: TH18-A
RE
CO
VE
RY
(%
)
SA
MP
LE N
O
SA
MP
LE T
YP
E
SOILDESCRIPTION
00
Page 1 of 1
DE
PT
H (
m)
DR
ILLI
NG
DE
TA
ILS
Alignment:
10
0
Final Depth of Hole: 8.2 mDepth to Top of Rock: 3.5 m
Station/Offset:
COMMENTSTESTING
Drillers Estimate{G % S % F %}
Drilling Company: Sea to Sky Drilling
23783
SUMMARY LOG
Datum: UTM Nad 83, Zone 11
Northing/Easting: 5539703.29 , 403384.76
Elevation: 1139.01 m
DYNAMIC CONE (BLOWS/300 mm)
MO
T-S
OIL
-RE
V2-
TE
L M
OD
237
83_C
OR
TIA
NA
BR
IDG
E_2
018
TE
ST
HO
LES
_MO
TI F
OR
MA
T.G
PJ
MO
T-D
RA
FT
-RE
V2.
GD
T 5
/10/
18
LW %W %
20 40 60 80P W%
SPT "N" (BLOWS/300 mm) Natural Vane (KPa) Remold Vane (KPa)
100 200 300 400 Pocket Penetrometer Shear Strength (kPa)
4
8
4222
31722
SPT
R5
R4-R5
R5
4
5
2
0
3
Joints; undulating to stepped,rough, infilled
Joints; undulating, moderatelyrough, infilledDiscontinuity; planar to undulating,moderately rough, infilledJoints; planar to curved, rough,infilled
Discontinuity; planar, moderatelyrough, infilled
Joints; planar, smooth to rough,infilled
Very coarse, PORPHYRITICGRANITE; strong to verystrong; slightly weathered tofresh
ANDESITE
Very coarse, PORPHYRITICGRANITE; strong to verystrong; slightly weathered tofresh
ANDESITE
Very coarse, PORPHYRITICGRANITE; strong to verystrong; slightly weathered tofresh
End of Test Hole at 8.23 mdepth.
Note 1: Logging carried out bySea to Sky Drilling for MoTI.The field logs were provided toThurber Engineering Ltd. fordrafting.
Note 2: Test Hole closuresummary was not provided.
1
2
3
Fair
Fair
Excellent
F-SW
F-SW
F-SW
4.57
1.26
6.13
4.96
6.24
Start NQcoring at4.27mdepth.
DIS
CO
NT
INU
ITY
SP
AC
ING
RECOVERY %
RQD %
Alignment:
Northing/Easting: 5539703.29 , 403384.76
Elevation: 1139.01 m
14
5
6
7
8
9
10
11
12
13
STRUCTURALDISCONTINUITYDESCRIPTION
Datum: UTM Nad 83, Zone 11
4
Drilling Company: Sea to Sky Drilling
Driller: Chad Brown
Drilling Method: Wash Rotary
ROCK CORE LOG
ELE
VA
TIO
N (
m)
1134
1133
1132
1131
1130
1129
1128
1127
1126
5
6
7
8
9
10
11
12
13
44
Page 1 of 1
Logged by: Reviewed by: WRW
Location: Near Cherryville, B.C.
DE
PT
H (
m)
DR
ILLI
NG
DE
TA
ILS
CO
RE
RU
N N
O
RO
CK
SY
MB
OL
CLA
SSIF
ICAT
ION
# O
F JO
INTS
Thurber Engineering Ltd. / Sea toSky Drilling
ROCK MASSDESCRIPTION
Prepared by:
HW HighlyCW CompletelyRS Residual Soil
F FreshSW SlightlyMW Moderately
WeatheringR3 Medium Strong 25-50R4 Strong 50-100R5 Very Strong 100-250R6 Extremely Strong >250
Rock Strength (MPa)R0 Extremely Weak >1R1 Very Weak 1-5R2 Weak 5-25
INT
AC
T R
OC
KS
TR
EN
GT
H
WE
AT
HE
RIN
G
Discontinuity Spacing:No. of fractures/m
Final Depth of Hole: 8.2 mDepth to Top of Rock: 3.5 m
Drill Hole #: TH18-A
Coordinates Surveyed
Date(s) Drilled: May 16, 2018
Drill Make/Model: Mobile B-53
Project: Cortiana Bridge
Station/Offset:
23783
CO
RE
QU
ALI
TY
I s(5
0)(M
pa)
INST
ALLA
TIO
N
20 40 60 80
MO
T-R
OC
K-R
EV
2B-M
OD
BY
TE
L 2
3783
_CO
RT
IAN
A B
RID
GE
_201
8 T
ES
T H
OLE
S_M
OT
I FO
RM
AT
.GP
J M
OT
-DR
AF
T-R
EV
2B.G
DT
5/1
0/18
GP
CB/SB
GP
BR
1.07m
2.9m
3.66m
4.57m
Sandy GRAVEL (FILL)
GRAVEL and BOULDERS (probable FILL)
GRAVEL
BEDROCK
End of Test Hole at 4.57 m depth.
Note 1: Logging carried out by Sea to SkyDrilling for MoTI. The field logs wereprovided to Thurber Engineering Ltd. fordrafting.
Note 2: Test Hole closure summary wasnot provided.
ELE
VA
TIO
N (
m)
1
2
3
4
5
6
7
8
9
LegendSample Type:
S-SplitSpoon
O-Odex(air rotary)
T-ShelbyTube
C-CoreA-Auger G-Grab V-Vane
1
2
3
4
5
6
7
8
9
Driller: Chad Brown
Drill Make/Model: Mobile B-53
CLA
SSIF
ICAT
ION
Location: Near Cherryville, B.C.
Date(s) Drilled: May 16, 2018
Drilling Method: Wash RotaryCoordinates Surveyed
Project: Cortiana Bridge
L#-Lab SampleW-Wash(mud return)
1138
1137
1136
1135
1134
1133
1132
1131
1130
1129
Thurber Engineering Ltd. / Sea toSky Drilling
Prepared by:
Logged by: Reviewed by: WRW
SO
IL S
YM
BO
L
Drill Hole #: TH18-B
RE
CO
VE
RY
(%
)
SA
MP
LE N
O
SA
MP
LE T
YP
E
SOILDESCRIPTION
00
Page 1 of 1
DE
PT
H (
m)
DR
ILLI
NG
DE
TA
ILS
Alignment:
10
0
Final Depth of Hole: 3.7 mDepth to Top of Rock: 3.7 m
Station/Offset:
COMMENTSTESTING
Drillers Estimate{G % S % F %}
Drilling Company: Sea to Sky Drilling
23783
SUMMARY LOG
Datum: UTM Nad 83, Zone 11
Northing/Easting: 5539698.67 , 403395.84
Elevation: 1138.84 m
DYNAMIC CONE (BLOWS/300 mm)
MO
T-S
OIL
-RE
V2-
TE
L M
OD
237
83_C
OR
TIA
NA
BR
IDG
E_2
018
TE
ST
HO
LES
_MO
TI F
OR
MA
T.G
PJ
MO
T-D
RA
FT
-RE
V2.
GD
T 5
/10/
18
LW %W %
20 40 60 80P W%
SPT "N" (BLOWS/300 mm) Natural Vane (KPa) Remold Vane (KPa)
100 200 300 400 Pocket Penetrometer Shear Strength (kPa)
SPT
Start NQcoring at3.66mdepth.
AS
GP
GP/SB
BR
0.2m
2.74m
3.35m
8.38m
1 13
ASPHALT
Loose, wet, brown, sandy GRAVEL (FILL)
GRAVEL and COBBLES
BEDROCK(see Rock Core logs)
End of Test Hole at 8.38 m depth.
Note 1: Logging carried out by Sea to SkyDrilling for MoTI. The field logs wereprovided to Thurber Engineering Ltd. fordrafting.
Note 2: Test Hole closure summary wasnot provided.
ELE
VA
TIO
N (
m)
1
2
3
4
5
6
7
8
9
LegendSample Type:
S-SplitSpoon
O-Odex(air rotary)
T-ShelbyTube
C-CoreA-Auger G-Grab V-Vane
1
2
3
4
5
6
7
8
9
Driller: Chad Brown
Drill Make/Model: Mobile B-53
CLA
SSIF
ICAT
ION
Location: Near Cherryville, B.C.
Date(s) Drilled: May 16, 2018
Drilling Method: Wash RotaryCoordinates Surveyed
Project: Cortiana Bridge
L#-Lab SampleW-Wash(mud return)
1138
1137
1136
1135
1134
1133
1132
1131
1130
1129
Thurber Engineering Ltd. / Sea toSky Drilling
Prepared by:
Logged by: Reviewed by: WRW
SO
IL S
YM
BO
L
Drill Hole #: TH18-C
RE
CO
VE
RY
(%
)
SA
MP
LE N
O
SA
MP
LE T
YP
E
SOILDESCRIPTION
00
Page 1 of 1
DE
PT
H (
m)
DR
ILLI
NG
DE
TA
ILS
Alignment:
10
0
Final Depth of Hole: 8.4 mDepth to Top of Rock: 3.4 m
Station/Offset:
COMMENTSTESTING
Drillers Estimate{G % S % F %}
Drilling Company: Sea to Sky Drilling
23783
SUMMARY LOG
Datum: UTM Nad 83, Zone 11
Northing/Easting: 5539678.68 , 403404.2
Elevation: 1138.57 m
DYNAMIC CONE (BLOWS/300 mm)
MO
T-S
OIL
-RE
V2-
TE
L M
OD
237
83_C
OR
TIA
NA
BR
IDG
E_2
018
TE
ST
HO
LES
_MO
TI F
OR
MA
T.G
PJ
MO
T-D
RA
FT
-RE
V2.
GD
T 5
/10/
18
LW %W %
20 40 60 80P W%
SPT "N" (BLOWS/300 mm) Natural Vane (KPa) Remold Vane (KPa)
100 200 300 400 Pocket Penetrometer Shear Strength (kPa)
84443
SPT
R5
R5
R3
2
2
10
10
3
Joints; planar to undulating,moderately rough, infilled
Joints; planar to undulating,rough, infilled
Joints; irregular, rough
Joints; irregular, rough
Joints; planar to undulating,moderately rough, infilled
Very coarse, PORPHYRITICGRANITE; strong to verystrong; slightly weathered tofresh
End of Test Hole at 8.38 mdepth.
Note 1: Logging carried out bySea to Sky Drilling for MoTI.The field logs were provided toThurber Engineering Ltd. fordrafting.
Note 2: Test Hole closuresummary was not provided.
1
2
3
Excellent
Good
Fair
F-SW
F-SW
F-SW
6.05
4.71
0.63
6.33
Start NQcoring at3.66mdepth.
DIS
CO
NT
INU
ITY
SP
AC
ING
RECOVERY %
RQD %
Alignment:
Northing/Easting: 5539678.68 , 403404.2
Elevation: 1138.57 m
13.7
4
5
6
7
8
9
10
11
12
13
STRUCTURALDISCONTINUITYDESCRIPTION
Datum: UTM Nad 83, Zone 11
3.7
Drilling Company: Sea to Sky Drilling
Driller: Chad Brown
Drilling Method: Wash Rotary
ROCK CORE LOG
ELE
VA
TIO
N (
m)
1134
1133
1132
1131
1130
1129
1128
1127
1126
1125
4
5
6
7
8
9
10
11
12
13
3.73.7
Page 1 of 1
Logged by: Reviewed by: WRW
Location: Near Cherryville, B.C.
DE
PT
H (
m)
DR
ILLI
NG
DE
TA
ILS
CO
RE
RU
N N
O
RO
CK
SY
MB
OL
CLA
SSIF
ICAT
ION
# O
F JO
INTS
Thurber Engineering Ltd. / Sea toSky Drilling
ROCK MASSDESCRIPTION
Prepared by:
HW HighlyCW CompletelyRS Residual Soil
F FreshSW SlightlyMW Moderately
WeatheringR3 Medium Strong 25-50R4 Strong 50-100R5 Very Strong 100-250R6 Extremely Strong >250
Rock Strength (MPa)R0 Extremely Weak >1R1 Very Weak 1-5R2 Weak 5-25
INT
AC
T R
OC
KS
TR
EN
GT
H
WE
AT
HE
RIN
G
Discontinuity Spacing:No. of fractures/m
Final Depth of Hole: 8.4 mDepth to Top of Rock: 3.4 m
Drill Hole #: TH18-C
Coordinates Surveyed
Date(s) Drilled: May 16, 2018
Drill Make/Model: Mobile B-53
Project: Cortiana Bridge
Station/Offset:
23783
CO
RE
QU
ALI
TY
I s(5
0)(M
pa)
INST
ALLA
TIO
N
20 40 60 80
MO
T-R
OC
K-R
EV
2B-M
OD
BY
TE
L 2
3783
_CO
RT
IAN
A B
RID
GE
_201
8 T
ES
T H
OLE
S_M
OT
I FO
RM
AT
.GP
J M
OT
-DR
AF
T-R
EV
2B.G
DT
5/1
0/18
AS
GP/SB
GP/SB
BR
0.13m
0.91m
5.18m
6.1m
ASPHALT
Compact GRAVEL
GRAVEL and COBBLES
- contains boulders
BEDROCK
End of Test Hole at 6.10 m depth.
Note 1: Logging carried out by Sea to SkyDrilling for MoTI. The field logs wereprovided to Thurber Engineering Ltd. fordrafting.
Note 2: Test Hole closure summary wasnot provided.
ELE
VA
TIO
N (
m)
1
2
3
4
5
6
7
8
9
LegendSample Type:
S-SplitSpoon
O-Odex(air rotary)
T-ShelbyTube
C-CoreA-Auger G-Grab V-Vane
1
2
3
4
5
6
7
8
9
Driller: Chad Brown
Drill Make/Model: Mobile B-53
CLA
SSIF
ICAT
ION
Location: Near Cherryville, B.C.
Date(s) Drilled: May 17, 2018
Drilling Method: Wash RotaryCoordinates Surveyed
Project: Cortiana Bridge
L#-Lab SampleW-Wash(mud return)
1138
1137
1136
1135
1134
1133
1132
1131
1130
1129
Thurber Engineering Ltd. / Sea toSky Drilling
Prepared by:
Logged by: Reviewed by: WRW
SO
IL S
YM
BO
L
Drill Hole #: TH18-D
RE
CO
VE
RY
(%
)
SA
MP
LE N
O
SA
MP
LE T
YP
E
SOILDESCRIPTION
00
Page 1 of 1
DE
PT
H (
m)
DR
ILLI
NG
DE
TA
ILS
Alignment:
10
0
Final Depth of Hole: 6.1 mDepth to Top of Rock: 5.2 m
Station/Offset:
COMMENTSTESTING
Drillers Estimate{G % S % F %}
Drilling Company: Sea to Sky Drilling
23783
SUMMARY LOG
Datum: UTM Nad 83, Zone 11
Northing/Easting: 5539683.03 , 403391.91
Elevation: 1138.66 m
DYNAMIC CONE (BLOWS/300 mm)
MO
T-S
OIL
-RE
V2-
TE
L M
OD
237
83_C
OR
TIA
NA
BR
IDG
E_2
018
TE
ST
HO
LES
_MO
TI F
OR
MA
T.G
PJ
MO
T-D
RA
FT
-RE
V2.
GD
T 5
/10/
18
LW %W %
20 40 60 80P W%
SPT "N" (BLOWS/300 mm) Natural Vane (KPa) Remold Vane (KPa)
100 200 300 400 Pocket Penetrometer Shear Strength (kPa)
SPT
GP
GP/SB
GP
GP/SB
BR
1.52m
2.29m
4.27m
6.4m
7.01m
Loose to compact GRAVEL
GRAVEL and COBBLES
Compact GRAVEL
GRAVEL and COBBLES
BEDROCK (Inferred)
End of Test Hole at 7.01 m depth.
Note 1: Logging carried out by Sea to SkyDrilling for MoTI. The field logs wereprovided to Thurber Engineering Ltd. fordrafting.
Note 2: Test Hole closure summary wasnot provided.
ELE
VA
TIO
N (
m)
1
2
3
4
5
6
7
8
9
LegendSample Type:
S-SplitSpoon
O-Odex(air rotary)
T-ShelbyTube
C-CoreA-Auger G-Grab V-Vane
1
2
3
4
5
6
7
8
9
Driller: Chad Brown
Drill Make/Model: Mobile B-53
CLA
SSIF
ICAT
ION
Location: Near Cherryville, B.C.
Date(s) Drilled: May 17, 2018
Drilling Method: Wash RotaryCoordinates Surveyed
Project: Cortiana Bridge
L#-Lab SampleW-Wash(mud return)
1138
1137
1136
1135
1134
1133
1132
1131
1130
Thurber Engineering Ltd. / Sea toSky Drilling
Prepared by:
Logged by: Reviewed by: WRW
SO
IL S
YM
BO
L
Drill Hole #: TH18-E
RE
CO
VE
RY
(%
)
SA
MP
LE N
O
SA
MP
LE T
YP
E
SOILDESCRIPTION
00
Page 1 of 1
DE
PT
H (
m)
DR
ILLI
NG
DE
TA
ILS
Alignment:
10
0
Final Depth of Hole: 7.0 mDepth to Top of Rock: 6.6 m
Station/Offset:
COMMENTSTESTING
Drillers Estimate{G % S % F %}
Drilling Company: Sea to Sky Drilling
23783
SUMMARY LOG
Datum: UTM Nad 83, Zone 11
Northing/Easting: 5539683.89 , 403381.41
Elevation: 1139.04 m
DYNAMIC CONE (BLOWS/300 mm)
MO
T-S
OIL
-RE
V2-
TE
L M
OD
237
83_C
OR
TIA
NA
BR
IDG
E_2
018
TE
ST
HO
LES
_MO
TI F
OR
MA
T.G
PJ
MO
T-D
RA
FT
-RE
V2.
GD
T 5
/10/
18
LW %W %
20 40 60 80P W%
SPT "N" (BLOWS/300 mm) Natural Vane (KPa) Remold Vane (KPa)
100 200 300 400 Pocket Penetrometer Shear Strength (kPa)
SPT