15
ENGINEERING LTD. 287 Tiffin Street, Unit 10, Barrie, Ontario L4N 7R8 TEL: (705) 722-4638 FAX: (705) 722-4958 GEOSPEC ENGINEERING LTD. 11-1655 Slope Rev Mofan 239 Bayview Drive Barrie 1 August 2, 2011 Mofan Holdings Inc. 33 Saunders Road Barrie, Ontario L4N 9A7 Attn: Mr. M. Fanelli Re: Review of Slope Stability 239 Bayview Drive, Barrie 11-1655 Dear Mose, As requested, Geospec Engineering Ltd. has completed a review of the impact to slope stability of the proposed Bayview Drive Development, at the referenced site. In this regard, we have completed a site inspection and supporting test pit investigation. Background The site servicing plans provided depict the proposed building development as well as show the existing slopes located to the north and east. Based upon these drawings, it is our understanding that a 2,200 m 2 building is proposed within 2 to 20 meters of the top of slope. A secondary building is proposed away from the slope. The supporting test pit investigation carried out by Geospec Engineering Ltd., included six test pits scattered over the property and slope, as shown on the attached Test Pit & Cross Section Location Plan. The test pits were advanced to a maximum depth of 4.5 meters below the original grade levels predominantly terminating within silty sand till. Detailed descriptions of the subsurface conditions encountered are provided in the attached The Test Pit Visual Logs (Enclosure N°s 2 - 4) and Grain Size Distributions Charts (Enclosure N° 5). Briefly, the subsurface conditions encountered at the test pits comprised a heterogeneous fill over a compact to very dense silty sand till that extended to the full depth investigated with occasional pockets of sand. The till exhibited low permeability and resistance to erosion. In addition, neither free flowing groundwater nor seepage was encountered during the investigation. We understand that the overlying fill is to be removed and replaced with engineered fill. The geotechnical characteristics of the fill will be dependent upon the material utilized. Nevertheless, an Engineered Fill must be compacted to 100% Standard Proctor Dry Density which would be considered a very dense material. As such an appropriate Angle of Internal Friction for the fill would be in the order of 32° which represents a slope inclined at 1.6:1.

Mr. M. Fanelli 239 Bayview Drive, Barrie 11-1655 Geospec

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ENGINEERING LTD.287 Tiffin Street, Unit 10, Barrie, Ontario L4N 7R8 TEL: (705) 722-4638 FAX: (705) 722-4958

GEOSPEC ENGINEERING LTD. 11-1655 Slope Rev Mofan 239 Bayview Drive Barrie 1

August 2, 2011

Mofan Holdings Inc.33 Saunders RoadBarrie, OntarioL4N 9A7

Attn: Mr. M. Fanelli

Re: Review of Slope Stability239 Bayview Drive, Barrie 11-1655

Dear Mose,

As requested, Geospec Engineering Ltd. has completed a review of the impact to slopestability of the proposed Bayview Drive Development, at the referenced site. In thisregard, we have completed a site inspection and supporting test pit investigation.

Background

The site servicing plans provided depict the proposed building development as well asshow the existing slopes located to the north and east. Based upon these drawings, it isour understanding that a 2,200 m2 building is proposed within 2 to 20 meters of the top ofslope. A secondary building is proposed away from the slope.

The supporting test pit investigation carried out by Geospec Engineering Ltd., includedsix test pits scattered over the property and slope, as shown on the attached Test Pit &Cross Section Location Plan. The test pits were advanced to a maximum depth of 4.5meters below the original grade levels predominantly terminating within silty sand till.Detailed descriptions of the subsurface conditions encountered are provided in theattached The Test Pit Visual Logs (Enclosure N°s 2 - 4) and Grain Size DistributionsCharts (Enclosure N° 5). Briefly, the subsurface conditions encountered at the test pitscomprised a heterogeneous fill over a compact to very dense silty sand till that extendedto the full depth investigated with occasional pockets of sand. The till exhibited lowpermeability and resistance to erosion. In addition, neither free flowing groundwater norseepage was encountered during the investigation.

We understand that the overlying fill is to be removed and replaced with engineered fill.The geotechnical characteristics of the fill will be dependent upon the material utilized.Nevertheless, an Engineered Fill must be compacted to 100% Standard Proctor DryDensity which would be considered a very dense material. As such an appropriate Angleof Internal Friction for the fill would be in the order of 32° which represents a slopeinclined at 1.6:1.

GEOSPEC ENGINEERING LTD. 11-1655 Slope Rev Mofan 239 Bayview Drive Barrie 2

Slope Condition

A detailed visual review was carried out of the overall slope, on July 4. Based uponvisual observations, the slope was considered to vary in inclination from slight tomoderate. The slope was heavily treed by a variety of species some with trunk diameterin excess of 40 cm. Mature trees with a vertical trunk orientation suggest the slope hasbeen stable through the life of the tree.

A surface run-off erosion gulley was noted on the east slope and a dry creek bed wasnoted approximately 10 to 20 m from the bottom of the east slope.

Slope Geometry

The geodetic elevation of the top of slope was established to be approximately 268meters (ASL) as shown of the AECOM Site Servicing Plan. Furthermore, the bottom ofslope as depicted on the plan is shown as approximately 261 to 262 meters (ASL).

The datum elevations of the Top and Bottom of the Slope, as shown on the documentsprovided were established as follows:

Top of Slope: 268 m Toe of Slope: 261.5 m

Based upon the included topographical data the overall slope appears to be inclined at adegree in the order of 14-23° (~2 to 4 : 1) at representative topographic sections.

The Cross Sections of the existing slope are shown on the enclosed Test Pit & CrossSection Plan (Enclosure N° 1) and resulting Cross Sections (Enclosure N°s 6-9). Basedupon the Cross Sections, that are extended to the proposed driveway, the representativecritical portions of the slope from the Top of Slope to Bottom of Slope and steepestsection are detailed in Table 1.

GEOSPEC ENGINEERING LTD. 11-1655 Slope Rev Mofan 239 Bayview Drive Barrie 3

Table 1: Slope Inclination

Inclination of Slope

Section Length

(m)

Top of SlopeElevation

(m)

Bottomof Slope

Elevation(m)

Height(m) Horiz. Vert. Angle

Cross Section 1 13.6 267.76 262 5.8 2.4 1 23°

Cross Section 2 27 269.5 261.5 8.0 3.4 1 17°

Cross Section 3 20.6 268.35 261.5 6.9 3.0 1 18°

Cross Section 4 28.6 269 262 7.0 4.1 1 14°

Slope Stability

The existing slope was computer modeled with Slide 5.0 using the Analysis MethodsBishop Simplified and Janbu Simplified, which utilize the method of slices forestablishing Factors of Safety for various possible failure circles. The graphical depictionof the computer model is presented as Enclosure N° 10.

The results of the computer modeling, for the current slope represented by the CrossSection, revealed that the minimum Factor of Safety (FS) with respect to global failure is1.881. This value of Factor of Safety would suggest that the slope is stable. Nevertheless,the value is conservative in nature as it does not account for cohesion or vegetativerestraints. More importantly, the Factor of Safety relative to the proposed driveway is4.673. We do advise that this safety factor does not apply to surface sloughing due tosurface erosion.

Natural Hazard Considerations

The subject property proposed for development is situated on a plateau above theseasonally flowing Whiskey Creek. More specifically, the creek flows within a shallowvalley corridor that is confined by the valley walls within 0 to 20 meters of the Toe ofSlope as it passes the subject site. Consequently, the property represents a ConfinedSystem in which the Erosion Hazard Limit must be assessed for toe erosion allowance,stable slope and erosion access allowance.

GEOSPEC ENGINEERING LTD. 11-1655 Slope Rev Mofan 239 Bayview Drive Barrie 4

Geotechnically, our experience in the area has established that the slope is comprised ofshallow surface fill that will be replaced with Engineered Fill overlying dense silty sandtill with no evidence of groundwater seeps. Furthermore, the existing ratio of slopeinclination at the steepest section, as represented by Cross Section 1 is in the order of2.4:1 (horizontal : vertical) and minimal evidence of toe erosion is apparent.

Recommendations

We reiterate that the till in this area has both cohesion and internal friction. As such, anexcavation in the till has the capacity to stand vertically for extended periods.Disregarding cohesion, the till exhibits an Angle of Internal Friction in excess of 35°. Atthis site, the angle would represent a slope inclined at approximately 1.4:1, disregardingthe effects of erosion.

The required allowance for toe erosion in a Confined System where the bank material iscomprised of sand & silt, is one (1) meter where no evidence of active erosion is apparentand the river bank full width is less than 5 meters. The allowance is increased to 5 to 8meters when evidence of active erosion is apparent.

Therefore, accounting for a six (6) meter allowance for Erosion Access and maximum toeerosion for sand & silt of five (5) meters and a conservative allowance for stable slope of2:1, which corresponds to an inclination steeper than the existing slope, a maximumsetback of 27 meters from the creek is required.

Conclusion

Since the proposed driveway is located beyond 35 meters from the creek, it is ourconsidered opinion that the currently proposed position of the buildings within thedevelopment will not compromise the slope stability or negatively impact the slope.

It is assumed that the development will be constructed in accordance with standardbuilding code requirements and founded on soil of appropriate capacity which must beconfirmed by a representative of Geospec. Finally, any vegetation on the slope that isdamaged during the construction operations must be reinstated and exposed soil protectedfrom surface run-off erosion.

GEOSPEC ENGINEERING LTD. 11-1655 Slope Rev Mofan 239 Bayview Drive Barrie 5

We trust this letter meets with your approval. Should you have any questions or requireclarification on any aspect of this letter, please do not hesitate to contact the undersigned.

Respectfully,GEOSPEC ENGINEERING LTD.

K. Malcolm,Consulting Engineer

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ENGINEERING LTD.287 Tiffin Street, Unit 10, Barrie, Ontario L4N 7R8 TEL: (705) 722-4638 FAX: (705) 722-4958

GEOSPEC ENGINEERING LTD. 11-1655 239 Bayview Drive ENCLOSURE N° 2

TEST PIT VISUAL LOGSGEOSPEC ENGINEERING LTD. PROJECT NO: 11-1655

TEST HOLE N: 1 North east of proposed Building B Elev. 270.0 m (estimated)

DEPTH (cm) COLOUR DENSITY MOISTURE SOIL DESCRIPTION

0-200 Brown Loose MoistSilty SAND with trace gravel (FILL)Bulk Sample at 100cm, Moisture Content 6.9%Sand 67%, Silt 25% gravel 8%

200-440 BrownVery

DenseMoist

Silty SAND with trace gravel (Till)Bulk Sample at 320cm, Moisture Content 6.5%%

NB: No water observed in test pit.

TEST HOLE N: 2 East of Proposed Building B Elev. 270.0 m (estimated)

DEPTH (cm) COLOUR DENSITY MOISTURE SOIL DESCRIPTION

0-150 Brown Loose MoistSilty SAND with trace gravel (FILL)Bulk Sample at 50cm, Moisture Content 5.7%

150-290 Brown Dense MoistSilty SAND with trace gravel (Till)Bulk Sample at 240cm, Moisture Content 10.4%

290-440 Brown Compact MoistSAND with some siltBulk sample at 410cm, Moisture Content 5.4%Sand 87%, Silt 13%

NB: No groundwater observed in test pit.

ENGINEERING LTD.287 Tiffin Street, Unit 10, Barrie, Ontario L4N 7R8 TEL: (705) 722-4638 FAX: (705) 722-4958

GEOSPEC ENGINEERING LTD. 11-1655 239 Bayview Drive ENCLOSURE N° 3

TEST HOLE N: 3 North west of proposed Building B Elev. 270.2 m (estimated)

DEPTH (cm) COLOUR DENSITY MOISTURE SOIL DESCRIPTION

0-150 Brown Loose MoistSilty SAND with trace gravel (FILL)Bulk Sample at 70cm, Moisture Content 3.3%

150-450 BrownVery

DenseMoist

Silty SAND with trace gravel (Till)Bulk Sample at 300cm, Moisture Content 9.6%

NB: No water observed in test pit.

TEST HOLE N: 4 West of proposed Building B Elev. 271.0 m (estimated)

DEPTH (cm) COLOUR DENSITY MOISTURE SOIL DESCRIPTION

0-120 Brown Loose MoistSilty SAND with trace gravel & cobbles (FILL)Bulk Sample at 100cm, Moisture Content 5.1%

120-400 BrownVery

DenseMoist

Silty SAND with trace gravel (Till)Bulk Sample at 350cm, Moisture Content 11.6%Sand 61%, Silt 30%, Gravel 9%

NB: No water observed in test pit.

ENGINEERING LTD.287 Tiffin Street, Unit 10, Barrie, Ontario L4N 7R8 TEL: (705) 722-4638 FAX: (705) 722-4958

GEOSPEC ENGINEERING LTD. 11-1655 239 Bayview Drive ENCLOSURE N° 4

TEST HOLE N: 5 South west of proposed Building B Elev. 267.3 m (estimated)

DEPTH (cm) COLOUR DENSITY MOISTURE SOIL DESCRIPTION

0-100 Brown Loose MoistSilty SAND with trace gravel (FILL)Bulk Sample at 70cm, Moisture Content 6.8%

100-300 BrownVery

DenseMoist

Silty SAND with trace gravel (Till)Bulk Sample at 300cm, Moisture Content 8.7%

NB: No water observed in test pit.

TEST HOLE N: 6 South east of proposed Building B Elev. 267.2 m (estimated)

DEPTH (cm) COLOUR DENSITY MOISTURE SOIL DESCRIPTION

0-20 Black Loose Moist Topsoil

20-60 Brown Compact Moist Silty SAND

60-400 BrownVery

DenseMoist

Silty SAND with trace gravel (Till)Bulk Sample at 300cm, Moisture Content 8.1%

NB: No water observed in test pit.

ENGINEERING LTD.287 Tiffin Street, Unit 10, Barrie, Ontario L4N 7R8 TEL: (705) 722-4638 FAX: (705) 722-4958

DATE:

ENCLOSURE N°: 5

PROJECT N°:

/ DATE SAMPLED:

DATE RECEIVED:

DATE TESTED:

TP / m TP 2 / 4.1 m

Sand 87%, Silt 13%TP / m

TP = Test Pit Sand 61%, Silt 30%, Gravel 9%

GRAIN SIZE IN MILLIMETERS

PE

RC

EN

TP

AS

SIN

GP

ER

CE

NT

RE

TA

INE

D

Silty SAND with trace gravel

Sand 67%, Silt 25%, Gravel 8%

SAND with some silt

UNIFIED SOIL CLASSIFICATION SYSTEM (ASTM D 2487)

Silty Sand with trace Gravel

4 3.5

SAMPLED FROM: 1 1.0

LAB N° / TYPE: 73 Original Undisturbed July 13, 2011

SAMPLED BY: W.J.

SAMPLED TYPE: Bulk July 15, 2011

ou ss July 13, 2011

PROJECT: 239 Bayview Drive, Barrie 11-1655

GRAIN SIZE DISTRIBUTION CHART

CLIENT: Mofan Holdings Inc. July 18, 2011

Clay & SiltSand

Fine Medium Coarse

Gravel

Fine Coarse Co

bb

les

50

1"3/4

"

3/8

"

41650200

0

10

20

30

40

60

70

80

90

100

100 30 80

.53

"5

/8"

2" 3"

0

10

20

30

40

50

60

70

80

90

100

0.001 0.01 0.1 1 10 100

262.5

263

263.5

264

264.5

265

265.5

266

266.5

267

267.5

267.76

268.4 268.3

CL W

hiskey C

reek

Top of Slope

269.55

Pro

ject

Bo

un

da

ry

263

264

265

266

267

268

269

270

PROPOSED

DRIVEWAYSLOPE DETAILS:

: 1

%

°

2.4

42.4

23

2.4 : 1 42.4 23.°

CLIENT:

PROJECT:

Mofan Holdings Inc.

239 Bayview Drive, Barrie

CROSS SECTION 1287 Tiffin Street, Unit 10

Barrie, Ontario, L4N 7R8

TEL: (705) 722 - 1638

FAX: (705) 722 - 4958ENGINEERING LTD

DATE: July 11 / 2011

PROJECT Nº: 11 - 1655

ENCLOSURE Nº: 6

SCALE: NOT TO SCALE

261 261

261.4261.5

262

262.5

-8.6

-3.5

0.0

6.0

18.4

19.8

21.1

23.3

23.5

24.8

26.0

27.4

28.5

29.5

30.6

31.6

32.0

38.0

48.6

CL W

hiskey C

reek

Bottom of Slope

260

261

262

-10.0 0.0 10.0 20.0 30.0 40.0 50.0

263

263.5

264

264.5

265

265.5

266

266.5

267

268

268.5

269

269.5

270

CL W

hiskey C

reek

Top of Slope

269.6

Pro

ject

Bo

un

da

ry

264

266

268

270

272

PROPOSED

DRIVEWAY

SLOPE DETAILS:

: 1

%

°

3.4

29.6

16.5

3.4 : 1 29.6 16.5°

CLIENT:

PROJECT:

Mofan Holdings Inc.

239 Bayview Drive, Barrie

CROSS SECTION 2287 Tiffin Street, Unit 10

Barrie, Ontario, L4N 7R8

TEL: (705) 722 - 1638

FAX: (705) 722 - 4958ENGINEERING LTD

DATE: July 11 / 2011

PROJECT Nº: 11 - 1655

ENCLOSURE Nº: 7

SCALE: NOT TO SCALE

260.5

260.91

260.5

261

261.5

262

262.5

263

0.0

2.0

4.0

6.0

11.0

14.0

15.2

16.5

17.8

19.4

21.0

22.8

24.6

26.5

28.4

30.2

31.8

33.6

35.5

37.4

39.1

41.0

46.5

CL W

hiskey C

reek

Bottom of Slope

260

262

-5.0 5.0 15.0 25.0 35.0 45.0

262.5

263

263.5

264

264.5

265

265.5

266

266.5

267

267.5

268

268.35

268.5269

CL W

hiskey C

reek

Top of Slope

269.51

Pro

ject

Bo

un

da

ry

263

264

265

266

267

268

269

270

PROPOSED

DRIVEWAYSLOPE DETAILS:

: 1

%

°

3.0

33.3

18.4

3.0 33.3 18.4°

CLIENT:

PROJECT:

Mofan Holdings Inc.

239 Bayview Drive, Barrie

CROSS SECTION 3287 Tiffin Street, Unit 10

Barrie, Ontario, L4N 7R8

TEL: (705) 722 - 1638

FAX: (705) 722 - 4958ENGINEERING LTD

DATE: July 11 / 2011

PROJECT Nº: 11 - 1655

ENCLOSURE Nº: 8

SCALE: NOT TO SCALE

260.18

260.5

261

261.5

262

262.5

0.0

2.5

7.7

10.6

12.1

13.5

15.0

16.4

17.8

19.4

20.8

22.4

23.9

25.4

26.9

28.5

30.0

31.2

34.3

40.0

46.3

CL W

hiskey C

reek

Bottom of Slope

260

261

262

-5.0 5.0 15.0 25.0 35.0 45.0 55.0

267

266.5

265.5

265

264

263.5

263 263

263.5

264

264.5

265

265.5

266

266.5

267

268

268.5

269269.5

Top of Slope

269.6

En

d o

f D

raw

ing

Pro

ject

Bo

un

da

ry

264

266

268

270

272

PROPOSED

DRIVEWAY

SLOPE DETAILS:

: 1

%

°

4.1

24.5

13.8

4.1 : 1 24.5 13.8°

CLIENT:

PROJECT:

Mofan Holdings Inc.

239 Bayview Drive, Barrie

CROSS SECTION 4287 Tiffin Street, Unit 10

Barrie, Ontario, L4N 7R8

TEL: (705) 722 - 1638

FAX: (705) 722 - 4958ENGINEERING LTD

DATE: July 11 / 2011

PROJECT Nº: 11 - 1655

ENCLOSURE Nº: 9

SCALE: NOT TO SCALE

263

262.5

262

262.5

263

-16.0

-12.6

-11.2

-8.4

-7.0

-5.6

-4.3

-2.9

-1.5

0.0

1.8

3.5

5.2

6.7

8.3

9.6

11.5

14.5

17.0

19.4

21.5

23.6

26.0

28.6

34.0

Bottom of Slope

To

p o

f S

lop

e

21.0

260

262

-18.0 -8.0 2.0 12.0 22.0 32.0

1.881

4.673

1.8811.881

4.673

1.881

Slope Analysis - Slide 5.011-1655 Mofan 239 Bayview Drive

Global MinimumsMethod: janbu simplifiedFS: 1.881170Center: 19.724, 280.155Radius: 18.303Left Slip Surface Endpoint: 17.610, 261.974Right Slip Surface Endpoint: 33.319, 267.901Resisting Horizontal Force=333.106 kNDriving Horizontal Force=177.074 kN

Material PropertiesMaterial: Silty Sand TillStrength Type: Mohr-CoulombUnit Weight: 22 kN/m3Cohesion: 1 kPaFriction Angle: 35 degreesWater Surface: None

Geospec Engineering Ltd.Enclosure N° 10

Safety Factor

0.000

0.250

0.500

0.750

1.000

1.250

1.500

1.750

2.000

2.250

2.500

2.750

3.000

3.250

3.500

3.750

4.000

4.250

4.500

4.750

5.000

5.250

5.500

5.750

6.000+

31

03

00

29

02

80

27

02

60

25

0

-30 -20 -10 0 10 20 30 40 50 60

(48.600, 255.000)

(48.600, 268.300)(38.000, 268.400)(32.000, 267.760)

(18.400, 262.000)(0.000, 261.400)

(-10.000, 261.000)

(-10.000, 255.000)