minnesota department of...

M innesota Department of Transportation MEMO Mailstop 645 1400 Gervais Avenue Maplewood, MN 55109

DATE: August 4, 2008

TO: Dan Dorgan, State Bridge Engineer

Office of Bridges & Structures

FROM: Hossana Teklyes, Grad Engineer-2 Office of Materials

Foundations Unit

CONCUR: Gary Person, Foundations Engineer Office of Materials

SUBJECT: S.P. 6241-51 Bridge 62048 TH 280 Under Larpenteur Ave

Located 1.2 miles South of JCT of TH 36 Subsurface Investigation & Foundation Analysis

Project Description This report provides a foundation analysis and recommendations for a new bridge (62048) replacing bridge (6738). The new two-span bridge (62048) will use 36 inch prestressed concrete beams with a cast in place deck 96 feet wide by 168 feet long. The substructures are to be supported on spread footing foundations. Field Investigation and Foundation Conditions Braun Intertec, under a consultant contract for Mn/DOT, advanced three foundation borings in May of 2008. The subsurface investigation was performed at each abutment. Copies of the borings are included with this report. West Abutment The foundation soils encountered at the west abutment consist of 10-15 ft. of medium dense sand and gravel (to an approximate elevation of 923 ft.) followed by 5-10 ft. of very dense sand and gravel. The last 40-50 ft. of boring is predominantly dense fine sand with gravel. East Abutment The foundation soils encountered at the East Abutment consist of 10-12 ft. of medium sandy loam and clay loam soil (to an approximate elevation of 930 ft.) followed by 10 ft. of fine sand. The last 45-50 ft. of boring is predominantly dense fine sand with some gravels. Please refer to the attached boring logs for a more complete description of the foundation soils. Foundation Analysis Approximate roadway and footing elevations were determined from a Preliminary Bridge Plan provided by MnDOT’s Bridge Office. Recommended foundation types are presented in Table 1.

S.P.6241-51 Bridge 62048 Subsurface Investigation & Foundation Analysis August 4, 2008

2

Table 1: Recommended Foundation Types and Assumed Footing Elevations West Abutment Pier East Abutment

Bottom of Footing Elevation 925 ft. 916 ft. 925 ft.

Foundation Spread Footing Spread Footing Spread Footing

Boring Used for the analysis

STBR-3

STBR-2 STBR-2

Substructure Foundations Due to the dense nature of the soils present, shallow foundations are proposed and have been analyzed for use at the abutments and pier. Shallow Foundation – Service Limit State An LRFD method was used for the analysis of the spread footings, using parameters based on the moderately dense sandy soils present at the site. Foundation boring (SPT) data was used to predict the foundation settlement (service limit state). The SPT settlement prediction model uses the blow count (N) from the SPT test and empirical correlations. For each abutment and pier, one settlement graph was developed, with 1 and 1.5 inch settlement criteria. Normally the 1 inch settlement criterion is used. But if a greater nominal bearing capacity is needed, then the settlement criteria could be increased to 1.5 inches. The settlement at the time of setting the beams may be less than 1 inch since it is estimated that at least 50% of the total load will have been already been applied to the soil due to the construction of the footing and stem itself. To further minimize differential settlement directly underneath the footing and further reduce possible settlement, it is recommended that a 2 foot subcut be constructed, backfilled, and compacted with aggregate bedding beneath the footings. Where spread footings are used for bridges: “[FHWA recommends] that the performance of the shallow foundation be monitored, so that actual settlements can be determined and the settlement analysis method can be calibrated for a specific geology or region of the country.” (FHWA NHI-01-023). Please contact our office if there is interest in monitoring foundation performance with respect to load or deflection. Shallow Foundation – Strength Limit State The strength limit state of the soil’s nominal bearing capacity was computed for varying footing widths. The strength limit is not the limiting case for this site; the service limit settlement state will control the design. The following are the resistance factors for evaluation of the strength limit state performance limits based on the latest LRFD code. Bearing Resistance, using SPT = 0.45 Sliding, Cast-in-Place Concrete on Sand = 0.80 Refer to the following figures in the appendix for the nominal bearing resistance and service limit state for the substructures on this project. Figure 1: West Abutment – 1 & 1.5 inch settlement Figure 2: East Abutment – 1 & 1.5 inch settlement


3

Figure 3: Pier – 1 & 1.5 inch settlement Recommendations

Based on the existing conditions along with an analysis of the project soils, we recommend:

1. Topsoil and other organic material should be removed from areas where fill is to be placed. These soils

should be excavated and replaced with Granular Borrow (Mn/DOT spec. 3149.2B1) and compacted to maximum Standard Proctor density. Refer to Recommendation #3.

2. The bridge should be supported on spread footing foundations with capacities defined in the nominal

bearing resistance graphs (Figures 1 to 3). The graphs show predicted available geotechnical resistance based on footing width for the strength/extreme-event limit states and service limit state at each of the 3 foundation areas; a graph is presented for 1.0 inch of deflection and 1.5 inches of deflection. Recent studies have shown that most of the settlement at bridge abutments built on granular soils occurs during the construction of the foundations and placement of the soil backfill.

The SPT [Westergard] 1” and 1.5” settlement (blue & green line respectively) is presented in the same

chart as strength/extreme-event (red line). Note that the scales are different for the service limit state [left side] and strength/extreme-event limit state [right side] data. The service limit state is expected to control the design.

3. A 2 foot subcut is required beneath footings to further minimize differential settlement. Backfill subcut

with Aggregate Bedding (Mn/DOT Spec. 3149.2G) and compact to maximum Standard Proctor density. 4. The footings should be buried a minimum of 4.5 feet below the final ground line for frost protection. 5. Drainage shall be installed as appropriate at the footing locations to ensure that the bearing soils and soils

behind the abutment are free draining. Drainage should be provided from the base of the footing subcut soils and from the rear of the abutment walls, similar to retaining wall drainage plans as used on recent projects.

6. Any pipes (water mains or drainage culverts) should be appropriately gasketed or cased to minimize risk

of erosion from pipe leakage or breakage. 7. Embankment slopes are recommended to be constructed at 2H : 1V slopes, or shallower, for stability and

to reduce erosion from overland flow. Vegetation should be established as quickly as possible after construction to minimize the potential for erosion.

8. Please contact our office if there is interest in monitoring the loads and settlements for the foundations at

this bridge during construction so improved correlations can be developed for the geotechnical prediction methods based on observed field behavior.


4

Attachments: Spread Footing Bearing Resistance Graphs (Figures 1 to 3) Boring Plan & Profile SPT index sheets SPT Boring Logs STBR-1, STBR-2 & STBR-3 (Unique # 70685, 70686 & 70687) cc: D. Dorgan G. Engstrom T. Styrbicki R. Evbayekha D.VanDeusen File


Figure 1: West Abutment – 1 & 1.5 inch settlement

5

LRFD SP 6241-51 BR 62048

WEST ABUTMENT - Boring (STBR-3)

0.01.02.03.04.05.06.07.08.09.0

10.011.012.0

4 5 6 7 8 9 1011121314151617181920Effective Footing Width (ft.)

Nom

inal

Bea

ring

Res

ista

nce,

Ser

vice

Lim

it St

ate

(ksf

)

30.0

40.0

50.0

60.0

70.0

80.0

90.0

Nom

inal

Bea

ring

Res

ista

nce,

Str

engt

h &

Extr

eme

Even

t Lim

it St

ate

(ksf

)

Service Limit State -1" Settlement-Westergaard [SPT]Service Limit State -1.5" Settlement-Westergaard [SPT]Strength Limit State


Figure 2: East Abutment – 1 & 1.5 inch settlement

LRFD SP 6241-51 BR 62048

EAST ABUTMENT - Boring (STBR-2)

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

11.0

12.0


Nom

inal

Bea

ring

Res

ista

nce,

Ser

vice

Lim

it St

ate

(ksf

)

30.0

40.0

50.0

60.0

70.0

80.0

90.0

Nom

inal

Bea

ring

Res

ista

nce,

Str

engt

h &

Extr

eme

Even

t Lim

it St

ate

(ksf

)

Service Limit State -1" SettlementWestergaard [SPT]

Service Limit State -1.5" Settlement-Westergaard [SPT]

Strength Limit State

6


Figure 3: Pier – 1 & 1.5 inch Settlement

7

LRFD SP 6241-51 BR 62048

PIER - Boring (STBR-2)

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

11.0

12.0


Nom

inal

Bea

ring

Res

ista

nce,

Ser

vice

Lim

it St

ate

(ksf

)

25.0

35.0

45.0

55.0

65.0

75.0

Nom

inal

Bea

ring

Res

ista

nce,

Str

engt

h &

Extr

eme

Even

t Lim

it St

ate

(ksf

)

Service Limit State -1" SettlementWestergaard [SPT]

Service Limit State -1.5" Settlement-Westergaard [SPT]

Strength Limit State

10

20

18

18

STA. 20+13.51 AH

EQUATION:STA. 20+09.87 BK =

15

15

21

20

16

19

19

16

17

17

10’0

GENERAL PLAN

AZ. = 89^50’18.95"

AZ. = 89^50’18.95"

48’-0"

76’-0"

< S.W. RAMP (SWR)

< N.W. RAMP (NWR)

< T.H. 280 N.B. (280NB)< T.H. 280 S.B. (280SB)

WEST ABUTMENT

14’-

0"

GUTTERLINE

1

4

3

2

LARPENTEUR AVENUE W.B. (LARPW) P.O.T.

16+04.97 = T.H. 280 S.B. (280SB) P.O.C. 19+39.22

X = 546065.603 Y = 173208.670

> = 79^24’10.9"

1

LARPENTEUR AVENUE E.B. (LARPE) P.O.T.

16+14.26 = T.H. 280 S.B. (280SB) P.O.C. 18+90.32

X = 546075.036 Y = 173160.697

> = 78^40’21.0"

2

LARPENTEUR AVENUE E.B. (LARPE) P.O.T.

16+50.98 = T.H. 280 N.B. (280NB) P.O.C. 18+77.16

X = 546111.758 Y = 173160.800

> = 78^33’49.3"

3

5

P.T

. 15+

04.0

2

P.C

. 16+

98.3

0

< LARPENTEUR AVE. E.B. (LARPE)

< LARPENTEUR AVE. W.B. (LARPW)

BEGIN BRIDGE

STA. 15+48.84‘

BEGIN BRIDGE

STA. 15+39.50‘

END BRIDGE

STA. 17+07.52‘

EL

. 9

44

.50

2

EL

. 9

43

.50

2

-0.60%

94’-4"

9’-2"

14’-

0"

9’-2"

P.T

. 15+

02.6

8

P.C

. 17+

40.4

7

P.T

. 17+

64.2

8

P.T

. 17+

44.6

1

P.C

. 14+

69.3

0P

.C. 14+

66.0

2

P.T. 20+09.87P.T. 20+17.01 STA. 20+13.46 AH

EQUATION:STA. 20+17.01 BK =

P.C. 15+64.88

36’-0"

P.C. 15+61.99

1:2

2’-0"

(TY

P.)

{=5 4̂3’46.48"

{ = 5 4̂3’46.48"

{ = 5 4̂3’46.48"

{ = 5 4̂3’46.48"

{

=1̂

29’3

.05"

3̂0

V.P

.T. S

TA

. 15+

50.7

3

V.P

.C. S

TA

. 17+

17.3

7

INPLACE BRIDGE NO. 6738 TO BE REMOVED

UNDER BRIDGE PORTION OF CONTRACT.

BRIDGE NO. 6738 IS A 150.2’ LONG, 4 SPAN

CONCRETE DECK GIRDER BRIDGE THAT IS

68.3’ WIDE AND WAS BUILT IN 1954.

{ 1

’0.0

3"

=

3

9

84’-0"‘

84’-0"‘168’-0"‘

SPAN 2

SPAN 1

18

18

10

11

17

< S.E. RAMP (SER)

< N.E. RAMP (NER)

AZ

. =

355^16’5

8.4

9"

AZ

. = 3

40^00’3

1.9

3"

AZ

. = 3

45^19’5

5.9

3"

AZ

. =

348^02’01.7

4"

AZ. = 88^28’27.79"

AZ. = 92^29’31.82"

STBR-1

STBR-2

STBR-3

EAST ABUTMENT

EXISTING GROUND PROFILE

70’ LT.

< LARPE

22’ RT.

DEPTH OF STRUCTURE:

4’-1" GUTTER TO LOW BRIDGE

36M P.C.B. 13‘ LINES

925

18

18

21

< S.W. RAMP (SWR) < T.H. 280 N.B. (280NB)< T.H. 280 S.B. (280SB)

1:2

WEST ABUTMENT

GUTTERLINE

PROFILE GRADE

LARPENTEUR AVE. E.B.

(LARPE)

< LARPENTEUR AVE. E.B. (LARPE)

-0.60%

P.C. 15+64.88

36’-0"

P.C. 15+61.99

1:2

4’-0"

17

< S.E. RAMP (SER)

AZ

. =

348^02’01.7

4"

EAST ABUTMENT

pl SANDY LOAM, trace of G, dk brn

and blk, moist, stiff to Vstiff, fill

CLAY LOAM, brn, moist, Vstiff

SILT LOAM, tan, moist, firm

CLAY LOAM, w/G, brn, moist, Vstiff

SAND & GRAVEL with some Bldrs,

brn, moist, dense to Vdense

F SAND, w/G, lt brn, moist, Vdense

SAND & GRAVEL, brn, moist,

dense

F SAND, w/ G, lt brn, moist, dense


Vdense

F SAND, w/G, lt brn, moist, dense

SAND, w/G, brn, sat, dense

Bottom of Hole - 71’

Borehole then grouted with

bentonite

Multiple blow counts shownon single line represent 6 in.or partial penetration values

13

17

23

7

17

35

40

56

86

56

69

94

32

46

53

40

48

45

45

62 100/.25

939.7SPT Coh

(psf)N60

Elevation

STBR-1

pl SANDY LOAM, blk, moist,

Vloose, topsoil.

CLAY LOAM, lt brn, wet, soft, fill


meddense, fill

pl SANDY LOAM, w/G, brn, moist,

stiff

Nonpl SANDY LOAM, w/ layer of S,

brn, moist, meddense

F SAND, w/ G and some Bldrs, lt


SAND & GRAVEL w/ some Bldrs,

brn, moist, dense to Vdense

SAND w/G and some Bldrs, lt brn,

moist, meddense


brn, moist, dense

F SAND, trace of G, lt brn, moist,

meddense


to Vdense

F SAND w/ a little G, lt brn, moist

dense to Vdense

pl F SANDY LOAM, w/G, brn, moist

to wet, Vdense to meddense


Water measured at 70’ while

sampling and/or drilling


bentonite


3

14

13

18

13

12

25

16

50

70

55

26

45

25

30

47

55

34

39

43

60

60

68

29

42

50/.25

942.0SPTCoh

(psf) N60

Elevation

STBR-2

F SANDY LOAM, trace of G, blk,

moist, topsoil


dense fill


brn, wet, meddense, fill

CLAY LOAM, gry, wet, Vstiff, fill

SILT LOAM, tan, moist, meddense

slpl SANDY LOAM, w/ a little G,

tan, moist, meddense


brn, moist, Vdense to meddense

SAND w/G and some Bldrs, lt brn,

moist, meddense

SAND & GRAVEL w/some Bldrs,


F SAND w/G and some Bldrs, lt brn,

moist to 55’ then wet, meddense to

Vdense

Saturated

pl SANDY LOAM w/G, brn, moist,

Vdense


Water measured at 67’ while

sampling and/or drilling


bentonite


31

45

14

23

14

16

73

56

21

25

29

20

17

16

25

45

27

29

42

44

40

44

80

30

62

69

50/.05

940.0SPTCoh

(psf) N60

Elevation

STBR-3

EL. 910

EL. 920

EL. 930

EL. 940

EL. 950

EL. 900

EL. 890

EL. 880

EL. 870

EL. 860

EL. 850

EL. 910

EL. 920

EL. 930

EL. 940

EL. 950

EL. 900

EL. 890

EL. 880

EL. 870

EL. 860

EL. 850

916

925

925

PIER

Vane Shear Test Washed Sample (Collected during plug drilling)

Minnesota Department of Transportation Geotechnical Section

Boring Log Descriptive Terminology (English Units)

USER NOTES, ABBREVIATIONS AND DEFINITIONS - Additional information available in Geotechnical Manual. This boring was made by ordinary and conventional methods and with care deemed adequate for the Department's design purposes. Since this boring was not taken to gather information relating to the construction of the project, the data noted in the field and recorded may not necessarily be the same as that which a contractor would desire. While the Department believes that the information as to the conditions and materials reported is accurate, it does not warrant that the information is necessarily complete. This information has been edited or abridged and may not reveal all the information which might be useful or of interest to the contractor. Consequently, the Department will make available at its offices, the field logs relating to this boring. Since subsurface conditions outside each borehole are unknown, and soil, rock and water conditions cannot be relied upon to be consistent or uniform, no warrant is made that conditions adjacent to this boring will necessarily be the same as or similar to those shown on this log. Furthermore, the Department will not be responsible for any interpretations, assumptions, projections or interpolations made by contractors, or other users of this log. Water levels recorded on this log should be used with discretion since the use of drilling fluids in borings may seriously distort the true field conditions. Also, water levels in cohesive soils often take extended periods of time to reach equilibrium and thus reflect their true field level. Water levels can be expected to vary both seasonally and yearly. The absence of notations on this log regarding water does not necessarily mean that this boring was dry or that the contractor will not encounter subsurface water during the course of construction. WATER MEASUREMENT

Augered Plug Drilled Split Tube Sample (SPT N60 2 in. spilt tube with liners) Thin Wall Sample (3 in. Shelby Tube) Core Drilled (NV Core Barrel unless otherwise noted) Continuous Soil Sample Augered & Jetted Jetted Augered & Plug Drilled

WS

PD

CS

A/J Jet A/P

AB ........................ After Bailing AC ........................ After Completion AF......................... After Flushing w/C ....................... with Casing

Index Sheet No. 3.0 March 2003 G:\geotech\Public\Forms\INDEX30.doc

w/M ...................... with Mud WSD ..................... While Sampling/Drilling w/AUG.................. with Hollow Stem Auger MISCELLANEOUS NA ........................ Not Applicable w/ ......................... with w/o ....................... with out sat ........................ saturated DRILLING OPERATIONS AUG ................. Augered CD .................... Core Drilled DBD.................. Disturbed by Drilling DBJ .................. Disturbed by Jetting PD .................... Plug Drilled ST..................... Split Tube (SPT test) TW.................... Thinwall (Shelby Tube) WS.................... Wash Sample NSR.................. No Sample Retrieved

WH ................... Weight of Hammer WR ................... Weight of Rod Mud.................. Drilling Fluids in Sample CS .................... Continuous Sample SOIL/CORE TESTS SPT N60 ............ ASTM D1586 Modified Blows per foot with 140 lb. hammer and a standard energy of 210 ft-lbs. This energy represents 60% of the potential energy of the system and is the average energy provided by a Rope & Cathead system. MC.................... Moisture Content COH ................. Cohesion γ ....................... Sample Density LL..................... Liquid Limit PI...................... Plasticity Index Φ ...................... Phi Angle REC.................. Percent Core Recovered RQD ................. Rock Quality Description (Percent of total core interval consisting of unbroken pieces 4 inches or longer) ACL .................. Average Core Length (Average length of core that is greater than 4 inches long) Core Breaks .... Number of natural core breaks per 2-foot interval. DISCONTINUITY SPACING Fractures Distance Bedding Very Close........ <2 inches ............Very Thin Close ................ 2-12 inches .........Thin Mod. Close ....... 12-36 inches .......Medium Wide................. >36 inches ..........Thick DRILLING SYMBOLS

RELATIVE DENSITY Compactness - Granular Soils BPF

very loose....................................0-4 loose ...........................................5-10 medium dense ............................11-24 dense ..........................................25-50 very dense...................................>50

Consistency - Cohesive Soils BPF

very soft.......................................0-1 soft ..............................................2-4 firm ..............................................5-8 stiff ..............................................9-15 very stiff.......................................16-30 hard.............................................31-60 very hard .....................................> 60

COLOR blk .................. Black wht ...........White grn ................. Green brn............Brown orng ............... Orange yel.............Yellow dk ................... Dark lt ...............Light IOS ................. Iron Oxide Stained GRAIN SIZE /PLASTICITY VF............. Very Fine pl ............Plastic F ............... Fine slpl .........Slightly Cr ............. Coarse Plastic SOIL/ROCK TERMS C............... Clay Lmst .......Limestone L ............... Loam Sst ..........Sandstone S............... Sand Dolo........Dolostone Si.............. Silt wx...........weathered G .............. Gravel (No. 10 Sieve to 3 inches) Bldr .......... Boulder (over 3 inches) T ............... till (unsorted, nonstratified glacial deposits) Mn/DOT Triangular Textural Soil Classification System

100%

100%

C

90807060 50 40 302010

90

80

70

60

50

40

30

20

10

(plastic)

(slightly plastic)

SC

SCL CL

L SL SiL

Si

SiCL

LSS Si

90

80

70

60

50

40

30

20

10

100 %

% Sand % Clay

% Silt

62100/.25

pl SANDY LOAM, trace of G, dk brn and blk, moist, stiff toVstiff, fill

CLAY LOAM, brn, moist, Vstiff

SILT LOAM, tan, moist, firm

CLAY LOAM, w/G, brn, moist, Vstiff

SAND & GRAVEL with some Bldrs, brn, moist, dense toVdense

NSR

17

20

20

17

8.0931.79.0

930.7

11.0928.7

15.0924.7

13

17

23

7

17

35

40

, , ft. LT(ft.)

LocationDrilling

SHEET 1 of 3

Ramsey Co. Coordinate: X=546211 Y=1731227511

Longitude (West)=93°12'17.02"CME Automatic Calibrated 5/20/08Completed

Latitude (North)=44°59'29.47"

Drill Machine

Hammer

Ground Elevation

(Surveyed)MN Trunk Highway 280Trunk Highway/Location Boring No.

6241-51State Project Bridge No. or Job Desc.

STBR-1 939.7

(%)

U.S. Customary Units

5

10

15

20

25

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core

Index Sheet Code 3.0G:\GINT\PROJECTS-ACTIVE\6241-51_TH280_LARPENTEUR.GPJ

Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests

This boring was taken by Braun Intertec under aconsultant contract for Mn/DOT

or Member

UNIQUE NUMBER 70685

(Continued Next Page)

DepthCOH

Soil Class:P. Martin Rock Class: Edit: Date: 8/5/08

Breaks

Or Remarks

Elev.

SPT

MINNESOTA DEPARTMENT OF TRANSPORTATION - GEOTECHNICAL SECTIONLABORATORY LOG & TEST RESULTS - SUBSURFACE EXPLORATION

Pressuremeter Test:E = 288.4 tsfPL = 33.9 tsfPF = 17.2 tsf

SAND & GRAVEL with some Bldrs, brn, moist, dense toVdense (continued)

F SAND, w/G, lt brn, moist, Vdense

SAND & GRAVEL, brn, moist, dense


SAND & GRAVEL, brn, moist, Vdense

NSR

NSR

37.0902.7

44.0895.7

47.0892.7

49.0890.7

56

86

56

69

94

32

46

Ground Elevation



STBR-1 939.7

Mn/DOT GEOTECHNICAL SECTION - LOG & TEST RESULTS SHEET 2 of 3

(%)


30

35

40

45

50

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core

G:\GINT\PROJECTS-ACTIVE\6241-51_TH280_LARPENTEUR.GPJ

Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70685


DepthCOH


Breaks

Or Remarks

Elev.

SPT


Pressuremeter Test:E = 205.5 tsfPL = 28.9 tsfPF = 18.7

Pressuremeter Test:E = 106.4 tsfPL = 22.3 tsfPF = 17.1 tsfDriller switched to auger toget past shreddedpressuremeter probe parts.Pressuremeter Test:

SAND & GRAVEL, brn, moist, Vdense (continued)

F SAND, w/G, lt brn, moist, dense

SAND, w/G, brn, sat, dense

Bottom of Hole - 71'Borehole then grouted with bentonite

53.0886.7

68.0871.7

71.0868.7

53

40

48

45

45

Ground Elevation



STBR-1 939.7


(%)


55

60

65

70

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core


Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70685

DepthCOH


Breaks

Or Remarks

Elev.

SPT


50/.25

pl SANDY LOAM, blk, moist, Vloose, topsoil.

CLAY LOAM, lt brn, wet, soft, fill

SAND & GRAVEL, brn, moist, meddense, fill

pl SANDY LOAM, w/G, brn, moist, stiff

Nonpl SANDY LOAM, w/ layer of S, brn, moist, meddense

F SAND, w/ G and some Bldrs, lt brn, moist, meddense

SAND & GRAVEL w/ some Bldrs, brn, moist, dense to Vdense

NSR

NSR

3.0939.0

5.5936.5

7.0935.0

9.0933.0

12.0930.0

22.0920.0

3

14

13

18

13

12

25

16

50

, , ft. LT(ft.)

LocationDrilling

SHEET 1 of 4




Drill Machine

Hammer

Ground Elevation



STBR-2 942.0

(%)


5

10

15

20

25

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core


Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70686


DepthCOH


Breaks

Or Remarks

Elev.

SPT


SAND & GRAVEL w/ some Bldrs, brn, moist, dense to Vdense(continued)

SAND w/G and some Bldrs, lt brn, moist, meddense

SAND & GRAVEL w/ some Bldrs, brn, moist, dense

F SAND, trace of G, lt brn, moist, meddense

F SAND, w/ G, lt brn, moist, dense to Vdense

F SAND w/ a little G, lt brn, moist dense to Vdense

NSR

31.0911.0

33.0909.0

37.0905.0

42.0900.0

49.0893.0

70

55

26

45

25

30

47

55

34

Ground Elevation



STBR-2 942.0


(%)


30

35

40

45

50

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core


Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70686


DepthCOH


Breaks

Or Remarks

Elev.

SPT


F SAND w/ a little G, lt brn, moist dense to Vdense (continued)

pl F SANDY LOAM, w/G, brn, moist to wet, Vdense tomeddense

2

4

73.0869.0

39

43

60

60

68

Ground Elevation



STBR-2 942.0


(%)


55

60

65

70

75

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core


Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70686


DepthCOH


Breaks

Or Remarks

Elev.

SPT


pl F SANDY LOAM, w/G, brn, moist to wet, Vdense tomeddense (continued)

Bottom of Hole - 81'Water measured at 70' while sampling and/or drillingBorehole then grouted with bentonite

11

1281.0861.0

29

42

Ground Elevation



STBR-2 942.0


(%)


80

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core


Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70686

DepthCOH


Breaks

Or Remarks

Elev.

SPT


50/.05

F SANDY LOAM, trace of G, blk, moist, topsoil

SAND & GRAVEL, brn, moist, dense fill

SAND & GRAVEL w/ some Bldrs, brn, wet, meddense, fill

CLAY LOAM, gry, wet, Vstiff, fill

SILT LOAM, tan, moist, meddense

slpl SANDY LOAM, w/ a little G, tan, moist, meddense

SAND & GRAVEL w/ some Bldrs, brn, moist, Vdense tomeddense

SAND w/G and some Bldrs, lt brn, moist, meddense

NSR

NSR

2.0938.0

7.0933.0

9.5930.5

11.0929.0

14.0926.0

17.0923.0

24.0916.0

31

45

14

23

14

16

73

56

21

, , ft. LT(ft.)

LocationDrilling

SHEET 1 of 4




Drill Machine

Hammer

Ground Elevation



STBR-3 940.0

(%)


5

10

15

20

25

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core


Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70687


DepthCOH


Breaks

Or Remarks

Elev.

SPT


Borehole refusal at 9' depth.Boring offset 3' south andredrilled.

Attempted Thinwall - NSR

Hard drilling 18 to 24' and 30to 67'

SAND w/G and some Bldrs, lt brn, moist, meddense(continued)

SAND & GRAVEL w/some Bldrs, brn, moist, meddense

F SAND w/G and some Bldrs, lt brn, moist to 55' then wet,meddense to Vdense

27.0913.0

32.0908.0

25

29

20

17

16

25

45

27

29

42

Ground Elevation



STBR-3 940.0


(%)


30

35

40

45

50

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core


Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70687


DepthCOH


Breaks

Or Remarks

Elev.

SPT


F SAND w/G and some Bldrs, lt brn, moist to 55' then wet,meddense to Vdense (continued)

Saturated

18

75.0

44

40

44

80

30

Ground Elevation



STBR-3 940.0


(%)


55

60

65

70

75

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core


Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70687


DepthCOH


Breaks

Or Remarks

Elev.

SPT


pl SANDY LOAM w/G, brn, moist, Vdense

Bottom of Hole - 81'Water measured at 67' while sampling and/or drillingBorehole then grouted with bentonite

12

9

865.0

81.0859.0

62

69

Ground Elevation



STBR-3 940.0


(%)


80

(%) (ft)

(pcf)N60

FormationREC ACL

Soi

l

Dril

ling

Ope

ratio

n

Lith

olog

y

RQD Core


Roc

k

DE

PTH

(psf)MC(%)

Classification

Other Tests


or Member

UNIQUE NUMBER 70687

DepthCOH


Breaks

Or Remarks

Elev.

SPT


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