preliminary foundation report bailiwick road bridge … \\edison\branch\geotech\connecticut\50018422...
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Preliminary Foundation Report Town of Greenwich State Bridge Project No. 56-299 Town Project No. 06-44 Rehabilitation of Bridge No. 05491 Bailiwick Road Bridge over The Byram River Town of Greenwich, CT October 2011
Prepared by:
Dewberry-Goodkind, Inc.
59 Elm Street, Suite 101
New Haven, CT 06510
Preliminary Foundation Report Town of Greenwich State Bridge Project No. 56-299 Town Project No. 06-44 Rehabilitation of Bridge No. 05491 Bailiwick Road Bridge over The Byram River Town of Greenwich, CT October 2011
Prepared by:
Dewberry-Goodkind, Inc.
59 Elm Street, Suite 101
New Haven, CT 06510
Eugene J. Schwarzrock, P.E. Date Connecticut License No. PEN.0022516
\\edison\branch\Geotech\Connecticut\50018422 Bailiwick Road\Foundation Report.docx
PRELIMINARY FOUNDATION REPORT
TOWN OF GREENWICH
STATE BRIDGE PROJECT NO. 56-299
TOWN PROJECT NO. 06-44
REHABILITATION OF BRIDGE NO. 05491
BAILIWICK ROAD BRIDGE OVER THE BYRAM RIVER
TOWN OF GREENWICH, CT
TABLE OF CONTENTS
PROJECT DESCRIPTION ......................................................................................................... 1
SUBSURFACE INVESTIGATION ............................................................................................ 2
SUBSURFACE CONDITIONS .................................................................................................. 2
DESIGN RECOMMENDATIONS
Bridge Abutments ................................................................................................................. 3
Wingwalls ............................................................................................................................. 4
Culverts ................................................................................................................................. 4
CONSTRUCTION RECOMMENDATIONS .............................................................................. 4
APPENDIX
General Location Map
Boring Location Plans (shown on General Plan & Elevation alternative plans)
Boring Logs
1 \\edison\branch\Geotech\Connecticut\50018422 Bailiwick Road\Foundation Report.docx
PROJECT DESCRIPTION
This project consists of the replacement and/or rehabilitation of Bridge No. 05491, which carries
Bailiwick Road over the Byram River in the Town of Greenwich, Connecticut, and which was
damaged during a major storm event that took place on April 15, 2007. The bridge is located
±55 ft. west of the intersection of Bailiwick Road and Riversville Road and was built in 1970
(see General Location Map in the Appendix).
The bridge is hydraulically deficient and during the 2007 storm event the Byram River
overtopped the bridge resulting in detachment of the north parapet and wash out of the
bituminous concrete pavement. Following the storm, the Town reopened the bridge with the
installation of a new wearing surface and temporary concrete barrier. The Town recently
replaced the storm-damaged parapet with funding from the Federal Emergency Management
Agency. Apart from the storm damage, the arch structure also exhibits spalled, scaled and
cracked concrete. This bridge provides the only official access to the neighborhood of
approximately 200 residents.
The existing bridge consists of a single span, concrete deck arch, ±33 ft. long, with masonry
fascias. The bridge carriers one lane of traffic in each of the eastbound and westbound directions
and has a curb to curb width of 27.1 ft.
The current scope of services includes conducting a Preliminary Engineering Study to evaluate
feasible alternatives to replace and/or rehabilitate the existing bridge in order to increase the
hydraulic opening to reduce future overtopping and have the ability to quickly reopen the bridge
to vehicular traffic following an overtopping event. The bridge replacement and rehabilitation
alternatives are discussed in the Structure Type Study Report, which was submitted separately by
Dewberry. Alternative 1 consists of a complete bridge replacement; Alternative 2 consists of
wingwall replacement at the bridge and the addition of two 9 ft. wide x 4 ft. tall relief culverts in
beneath the roadway ±21 ft. west of the bridge to allow additional river flow to pass the roadway
without overtopping. A copy of the alternative scheme plans from this report are included in the
Appendix. This report presents the findings of the preliminary subsurface investigation, as well
2 \\edison\branch\Geotech\Connecticut\50018422 Bailiwick Road\Foundation Report.docx
as preliminary design and construction recommendations based on the findings to date. These
recommendations will be finalized during the final design phase of the project.
SUBSURFACE INVESTIGATION
A soil investigation program consisting of three (3) borings was performed by Soiltesting, Inc. of
Oxford, Connecticut on August 10, 2011. The existing soil and bedrock conditions were
investigated in the vicinity of the two current bridge replacement/rehabilitation alternatives.
Borings B-1 and B-2 were performed behind the proposed east and west abutments, respectively,
of the bridge replacement alternative, while boring B-3 was performed just west of the relief
culverts proposed as part of the rehabilitation alternative. Two Boring Location Plans, based on
the General Plan & Elevation plans from the Bridge Type Study Report, and the boring logs are
included in the Appendix.
All three borings were drilled using a hollow stem auger to advance and maintain the hole. Soil
sampling was performed using a 2 in. O.D. split spoon sampler driven by a 140 lb. safety
hammer with a 30 in. drop. This procedure was performed in accordance with Standard
Penetration Test (ASTM D 1586). Borings were sampled at 5 ft. intervals from below the
existing asphalt pavement to auger refusal, which occurred between 6 and 11 ft. deep. Bedrock
was then cored 15 ft. at borings B-1 and B-3 using an N-sized core barrel to obtain samples of
the underlying bedrock in accordance with standard rock coring procedures (ASTM D 2113).
All drilling and sampling operations were observed by a geotechnical engineer and soil samples
were classified in accordance with D.M. Burmister in “Suggested Test Methods for Identification
of Soils” (ASTM, 1958).
SUBSURFACE CONDITIONS
The subsurface conditions are uniform among the three borings and consist of 4 ft. of granular
fill, underlain by medium dense to very dense sand and gravel to a depth of 8.5 to 11 ft.,
3 \\edison\branch\Geotech\Connecticut\50018422 Bailiwick Road\Foundation Report.docx
underlain by competent bedrock. The bedrock is hard gneiss, and was encountered at El. 124.1
in boring B-1, El. 123.5 in B-2, and El. 121.4 in B-3. The six 5 ft. long bedrock cores had
percent recoveries ranging from 90% to 97% with the exception of the last core obtained from B-
1 with a recovery of 77%. Rock quality designation(RQD)s ranged from 29% to 53% in boring
B-1, and 50% to 88% in Boring B-3, and generally increased with depth.
DESIGN RECOMMENDATIONS
Bridge Abutments
Based on the presence of competent bedrock at shallow depth, it is expected that the bridge
replacement alternative, if chosen, may be economically supported on spread footings founded
directly on bedrock - below El. ±124 at the east abutment and below El. ±123 at the west
abutment. Footings should be founded a minimum of 48 in. below the lowest adjacent grade to
protect against frost heave and should also have the top of footing even with the top of bedrock.
All footings may be constructed using a nominal bearing resistance of 45 tsf, assuming a
minimum footing width of 8 ft. Using the LRFD bearing capacity factor of 0.45, the factored
bearing resistance is 20 tsf.
Total settlement of the underlying bedrock will be elastic, less than ¼ in., and complete at the
end of construction. Scour has not been analyzed yet; however, it will not be an issue since the
footings will be founded directly on competent, scour resistant bedrock. The following
additional soil and bedrock properties are recommended for design:
Moist unit weight of soil, γt = 120 pcf (retained soil)
Moist unit weight of soil, γt = 120 pcf (select fill)
Buoyant unit weight of soil, γb = 65 pcf (retained soil and select fill)
Angle of internal friction, φf = 36o (retained soil and select fill)
= 48° (foundation bedrock)
Lateral earth pressure coefficients:
Active, KaR = 0.26
Passive, KpR = 3.85
Sliding resistance, tan δ = tan φf for CIP footing on bedrock
4 \\edison\branch\Geotech\Connecticut\50018422 Bailiwick Road\Foundation Report.docx
For LRFD design of the abutments and the closure walls the following resistance factors (φ) are
recommended for the Strength Limit State I design condition:
Resistance Factors
Bearing Resistance on rock = 0.45
Bearing Resistance on sand = 0.45
Sliding, CIP concrete on rock = 0.90
Sliding, CIP concrete on sand = 0.80
Wingwalls
Wingwalls will be required at various locations depending on which alternative is chosen for
construction. It is expected that recommendations similar to the above for the bridge will be
suitable for wingwall construction. Final recommendations will be issued in the final design
phase after their locations and depths are established.
Culverts
The twin culverts included in Alternative 2 may be founded on the very dense sand and gravel
which is present below the proposed invert elevation of El. 126.9 and above the top of bedrock at
El. ±121.4. The cutoff wall may extend completely or partially to the top of bedrock, depending
on the result of the scour analysis. These recommendations will be finalized in the final design
phase after the hydraulics analysis is completed.
CONSTRUCTION RECOMMENDATIONS
For footings founded on bedrock, the rock should be excavated to a generally level condition and
be free of soil and/or ice.
For footings founded on soil, footings should be constructed on minimally disturbed, in-situ soil
and should not be constructed on frozen or wet subgrade materials. All standing water should be
removed by pumping and the subgrade allowed to dry appreciably before constructing footings.
In wet weather conditions, a 4 in. thick layer of ¾ in. clean crushed stone may be placed below
the bottom of the footing to protect the excavation from softening prior to concrete placement.
All frozen subgrade soil should be removed and replaced with compacted structural fill, clean ¾
5 \\edison\branch\Geotech\Connecticut\50018422 Bailiwick Road\Foundation Report.docx
in. crushed stone, or additional concrete.
Construction of the bridge foundations will likely require a cofferdam and dewatering to remove
water entering from the river. Traditional cofferdam methods may be difficult to install due to
the shallow depth to bedrock and other, prefabricated cofferdam methods such as a Portadam
system which can provide a water resistant barrier for the excavation may be well suited for this
project. Portable pumps can then be used to remove water that enters the excavation.
For support of the roadway if staged construction is utilized, traditional sheeting along the
roadway centerline will also not be feasible due to the shallow depth to bedrock. A drilled-in
soldier pile and lagging system or soil nail wall will likely be suitable here.
Structural fill should consist of well graded, coarse to fine sand which has a maximum 15% non-
plastic fines and is free of organics and other deleterious materials. Neglecting any surface
topsoil or road base, the in-situ soils appear to be mostly gravelly sand and may be acceptable as
general site fill and/or structural fill. Structural fill material should be placed in maximum 9 in.
loose lifts and compacted to 95% of its maximum dry density at optimum moisture content as
determined by the Modified Proctor Density Test (ASTM D 1557). The placement of fill shall
be observed and tested by either the Sand Cone Method (ASTM D 1556) or Nuclear Density
Gauge Method (ASTM D 2922 and D 3012).
Excavations which extend deeper than 5 ft. and which are not supported by sheeting or shoring
shall be benched or sloped in accordance with current OSHA rules. The in-situ soils present on
this site are granular and it is recommended that temporary slopes be no steeper than 1V:1.5H.
APPENDIX
Bridge 05491
N
TOWN OF GREENWICH
GENERAL LOCATION MAP
BAILIWICK ROAD OVER THE BYRAM RIVER
BRIDGE 05491
Dewberry-Goodkind, Inc. 59 Elm Street, Suite 101 New Haven, Connecticut
SCALE: N.T.S. DATE: 8-13-11
Q 8 in.
8 in.
4 in. 8 in.
3 in.
3 in.
36 in.
2 in.
2 in.
2 in.
2 in.
2 in.
2 in.12 in
.
4 in.
3 in.1 in.
32 in.
6x1 in.
TW 5 in.
8 in.
80134
CL&P
8134A
CL&P
WF 46
WF 47WF 30
WF 31
WF 26WF 1
NO OUTLETSIGNNO PARK
SIGN
AT&TUGUF
BIT. L.O.
BIT. L.O.
JPG-3 (I. P
IN)
No. 05491
BRIDGE
AQUARION W
ATER CO.
EXPOSED WATER M
AIN
130
E 748231.49
N 578938.37
STA 105+41.46
PC
106+00
105+00
- -
-
-
-
- -
- - -
- - - -
- - -
- - -
- - - -
REHABILITATION OF BRIDGE
NO. 05491 BAILIWICK ROAD
OVER BYRAM RIVER
GREENWICH 56-299
GENERAL PLAN AND
STA 105+30.50
BEGIN BRIDGE
SKEW (TYP.)
22°56’ 45.09"
WINGWALL (TYP.)
REMOVE EXISTING
WINGWALL 1A
N 78°50’ 18.16 E
WINGWALL 1B
14’-0"
14’-0"
1’-10"
ABUTMENT
FACE OF
CURB LINE
LINE
CHORD
FACE OF ABUTMENT
WINGWALL 2B
WINGWALL 2A
ABUTMENT 1
BEARINGS
{ EXPANSION
ABUTMENT 2
{ FIXED BEARINGS,
SHOULDER
3’-0"
LANE
11’-0"
LANE
11’-0"
SHOULDER
3’-0"
1’-10"
1’-10"
B4B3B2B1 B5
(WOVEN GLASS FABRIC)
MEMBRANE WATERPROOFING
1" HMA S0.375 ON
2" HMA S0.5 ON
P.A.G.
�" / FT�" / FT
SLAB
8�" CONCRETE
} BAILIWICK ROAD
4 SPACES @ 6’-9" = 27’-0"
CROSS SECTIONSCALE: �" = 1’-0"
T.STRNAD/S.ERDAS
A. SESHADRI
GENERAL PLANSCALE: 1" = 10’
(VARIES)
2’-1�" TO 2’-8"
(VARIES)
4�" MAX.
RIVER
BYRAM
SH
LD
3’-0"
LA
NE
11’-0"
LA
NE
11’-0"
SH
LD
3’-0"
RA
DIA
L
1’-10"
(TYP.)
PAINTED TO COLOR BROWN
GALVANIZED & SHOP
BOX BEAM GUIDE RAIL,
} BAILIWICK ROAD
31’-8" TO 32’-4�"
INTERMEDIATE DIAPHRAGM (TYP.)
C12 x 20.7
LINE
CURB
1’-11�" TO 2’-7�"
(VARIES)
CONSTRUCTION
PROTECTED DURING
COMPANY) TO BE
(AQUARION WATER
EXISTING WATER MAIN
STA 105+89.60
END BRIDGE
STA 105+86.53
W.P. 2
STA 105+33.50
W.P. 1,
BRIDGE & FOOTINGS
CONCRETE ARCH
REMOVE EXISTING
(TYP.)
PAINTED TO COLOR BROWN
GALVANIZED & SHOP
BOX BEAM GUIDE RAIL,
(TYP.)
PROPOSED GRADE
SCALE: 1" = 10’
SOUTH ELEVATION
ABUTMENT 1
{ EXPANSION BEARINGS,
(ELEVATION VARIES)
ORDINARY HIGH WATERLINE
EL. TBD (TYP.)
BOTTOM OF FOOTING,
ABUTMENT 2
{ FIXED BEARINGS,53’-0"
ARCH BRIDGE & FOOTINGS
REMOVE EXIST. CONCRETE
(TYP.)
EL. 120.6|
ELEVATION-ALTERNATIVE 1
BEAM (TYP.)
WEATHERING STEEL
W21 X 101
TO COLOR BROWN (TYP.)
(HANDRAIL) ANODIZED
METAL BRIDGE RAIL
FORM LINERS (TYP.)
TREATMENT UTILIZING
WITH ARCHITECTURAL
2’-8" HIGH PARAPET& { BEAM B3
CHORD LINE
1’-3" APPROACH SLAB (TYP.)
3" HMA PAVEMENT OVER
CONCRETE DECK
BRIDGE WITH COMPOSITE
PROPOSED WEATHERING STEEL
(TYP.) (BY CL&P)
TO BE RELOCATED
EXIST. UTILITY POLE
8" CONCRETE PAVEMENT
2" HMA PAVEMENT OVER
EL. 130.82
LOW CHORD
CONCRETE DECK
BRIDGE WITH COMPOSITE
PROPOSED WEATHERING STEEL
EL. 130.8|
CHANNEL BED (SURVEY)
APPROX. EXIST.
UTILIZING FORMLINERS
ARCHITECTURAL TREATMENT
JOINT
1" EXPANSION
2
(T
YP.)
2’-8"
RECONSTRUCTION
FULL DEPTH HMA PAVEMENT
COLOR BROWN
ANODIZED TO
(HANDRAIL)
METAL BRIDGE RAIL
(TYP.)
ROADWAY
PROPOSED
ANODIZED TO COLOR BROWN
METAL BRIDGE RAIL (HANDRAIL)
GRANITE CURB
BORING B1)
EL. 124.1 (BASED ON
APPROX. TOP OF ROCK,
BORING B2)
EL. 123.5 (BASED ON
APPROX. TOP OF ROCK,
BORING B3)
EL. 121.4 (BASED ON
APPROX. TOP OF ROCK,
BORING LOCATION
DIRECTION OF TRAFFIC
LEGEND
B1
B2
B3
STRUCTURE TYPE STUDY
DESIGNER/DRAFTER:
CHECKED BY:
PROJECT TITLE: TOWN:
DRAWING TITLE:
PROJECT NO.
DRAWING NO.
SKETCH NO.
Filename:SHEET NO.REVISION DESCRIPTIONDATEREV.
DEPARTMENT OF PUBLIC WORKS
TOWN OF GREENWICH
SCALE AS NOTED
10/6/2011
BLOCK:
SIGNATURE/
DATE: APPROVED BY:
Dewberry-Goodkind, Inc.
...\SB_MSH_056_0299_GPN-ALT1.dgnPlotted Date:
- -
-
-
-
- -
- - -
- - - -
- - -
- - -
- - - -
REHABILITATION OF BRIDGE
NO. 05491 BAILIWICK ROAD
OVER BYRAM RIVER
GREENWICH 56-299
} BAILIWICK ROAD
36’-6"|
SCALE: �" = 1’-0"
SCALE: 1" = 10’
GENERAL PLAN ANDELEVATION-ALTERNATIVE 2
T.STRNAD/S.ERDAS
A.SESHADRI
38’-0"|
9"
3"
LANE
11’-0"
LANE
11’-0"
�"/FT �"/FT
3"
1’-6" 9"
(TYP.)
REINFORCEMENT
DRILL AND GROUT
(TYP.)
FACING
MASONRY
(TYP.)
WALL
SPANDREL
P.A.G.
ROAD
} BAILIWICK
HEADWALL 1
WINGWALL 3A
2’-6"
LINE
CURB
LINE
CURB
HEADWALL 2
WINGWALL 3BTO COLOR BROWN (TYP.)
GALVANIZED & SHOP PAINTED
BOX BEAM GUIDE RAIL,
RIVER
BYRAM
SCALE: 1" = 10’
GENERAL PLAN
WINGWALL 1B
20’-9�"
33’-8�"
WINGWALL 2B
15’-11"
SPANDREL WALL (ELEVATION VARIES)
WATERLINE
ORDINARY HIGH
EL. TBD (TYP.)
BOTTOM OF FOOTING,
PROPOSED GRADE
(TYP.)
EL. 120.61
SOUTH ELEVATION
PROPOSED ROADWAY
(TYP.)
STANDARD RIPRAPEL. TBD
CUT-OFF WALL
(TYP.)
MASONRY FACING
TO COLOR BROWN (TYP.)
GALVANIZED & SHOP PAINTED
BOX BEAM GUIDE RAIL,
(VARIES)
3’-0" MIN.
SHLD
3’-0"7"
CURBING
8"X16" SLOPED GRANITE
SLAB (TYP.)
1’-0" MOMENT
(THICKNESS VARIES)
GRANULAR FILL
CROSS SECTION
& EXTRADOS
ARCH INTRADOS
REPAIR EXISTING
(TYP.)
ANODIZED TO COLOR BROWN
METAL BRIDGE RAIL (HANDRAIL)
CURBING
6" GRANITE
PAVEMENT
8" CONCRETE
VARIES)
ARCH SLAB (THICKNESS
WINGWALL 1B
WINGWALL 1AWINGWALL 2A
GRANITE CURBING
8"X16" SLOPED
WINGWALL 2B
RA
DIA
L
14’-0"
CURBING
6" GRANITE
(BY CL&P) (TYP.)
TO BE RELOCATED
EXIST. UTILITY POLE
OVER FLOW
TO COLOR BROWN
(HANDRAIL) ANODIZED
METAL BRIDGE RAIL
HEADWALL 2
21’-8"
TO COLOR BROWN
(HANDRAIL) ANODIZED
METAL BRIDGE RAIL
CHANNEL BED (SURVEY)
APPROX. EXIST.
ARCH INTRADOS & EXTRADOS
REPAIR EXISTING
(TYP.)
EL. 127.4|
EL. 130.8|
CONSTRUCTION
PROTECTED DURING
COMPANY) TO BE
(AQUARION WATER
EXISTING WATER MAIN
3
PAVERS (TYP.)
3" CONCRETE BLOCK
2’-8"
SHLD
3’-0" MIN.
2’-8"
RA
DIA
L
11’-0"
RA
DIA
L
11’-0"
2’-3"
MIN.
14’-0"
B1
B2
B3
SH
LD
3’-0"
SH
LD
3’-0"
MIN.
BL
OC
K
PA
VE
RS
3’-0"
MIN.
CO
NC
RE
TE
(TYP.)
WITH CONCRETE WINGWALLS
WINGWALLS & REPLACE
REMOVE EXISTING MASONRY
PAVEMENT
MOMENT SLAB & INSTALL CONCRETE
REPLACE SPANDREL WALL, CONSTRUCT
& REPAIR ARCH INTRADOS & EXTRADOS.
REMOVE FILL ABOVE EXISTING ARCH
ARCH BRIDGE NO. 05491
EXISTING CONCRETE
PAVEMENT
LIMITS OF 8" CONCRETE
104+00
TO STA.
BORING B1)
EL. 124.1 (BASED ON
APPROX. TOP OF ROCK,
BORING B2)
EL. 123.5 (BASED ON
APPROX. TOP OF ROCK,
BORING B3)
EL. 121.4 (BASED ON
APPROX. TOP OF ROCK,
INV. EL. 126.9
RELIEF CULVERTS
(2)-9’-0" X 4’-0" CONC.
BORING LOCATION
DIRECTION OF TRAFFIC
LEGEND
STRUCTURE STUDY REPORT
DESIGNER/DRAFTER:
CHECKED BY:
PROJECT TITLE: TOWN:
DRAWING TITLE:
PROJECT NO.
DRAWING NO.
SKETCH NO.
Filename:SHEET NO.REVISION DESCRIPTIONDATEREV.
DEPARTMENT OF PUBLIC WORKS
TOWN OF GREENWICH
SCALE AS NOTED
10/6/2011
BLOCK:
SIGNATURE/
DATE: APPROVED BY:
Dewberry-Goodkind, Inc.
...\SB_MSH_056_0299_GPN-ALT2.dgnPlotted Date:
CULVERTS. BRIDGE NO. TBD
(2) 9’-0" X 4’-0" CONCRETE RELIEF
1’-6"
E 748231.49
N 578938.37
STA 105+41.46
PC
106+00
105+00
1301 in.
TW 10/16 i
n.
Q 8 in.
4 in. 8 in.
3 in.
3 in.
36 in.
2 in.
2 in.
2 in.
2 in.
2 in.
2 in.
4 in.
3 in.1 in.
32 in.
6x1 in.
TW 5 in.
8 in.
80134
CL&P
8134A
CL&P
WF 46
WF 47WF 30
WF 31
WF 26WF 1
NO OUTLETSIGNNO PARK
SIGN
AT&TUGUF
CATVUGUF
CL&PUGUF
BIT. L.O.
BIT. L.O.
JPG-3 (I. P
IN)
No. 05491
BRIDGE
AQUARION W
ATER CO.
EXPOSED WATER M
AIN
Boring Logs
Dewberry
ROUTE LOCAL NAME: Bailiwick Road Bridge Over Byram River - Bridge No. 05491 BORING NO. B-1
SECTION: Greenwich, CT FIELD BORING NO.
STATION: 105+98 OFFSET: 3 R REFERENCE LINE: Bailiwick Road N: 578925.511 E: 748287.288 GROUND ELEVATION: 132.6
BORING BY: Soiltesting, Inc. DATE STARTED: 8-10-2011 GROUND WATER ELEVATION
0 Hr. 126.6 (river elev.) 24 Hr.
Date: 8-10-2011 Date: INSPECTOR: Joseph Yu DATE COMPLETED: 8-10-2011
DEPTH (ft)
CASING BLOWS
SAMPLE DEPTH NO.
Blows on Spoon REC. (in)
SOIL DESCRIPTION AND STRATIFICATION
Depth/ Elev.(ft) 0 / 6 6 / 12 12 / 18
AUGER 9 in. Asphalt
⇓ S-1 1 3 43 54 16” FILL: Dark brown c-f SAND, some m-f Gravel, trace Silt
45 45
4/128.6
5
S-2 5 5.8 66 100/3 6” Gray brown c-f SAND, some c-f Gravel, trace Silt
Hard drilling from 6 to 8.5 ft., rig chatter
Auger refusal at 8.5 ft. Top of Rock 8.5/124.1
10 C1 8.5 13.5 Run 60” Dark gray to gray GNEISS, mod. to slightly weathered,
Rec. 97% mod. hard to hard, mod. to intensely fractured
RQD 29%
15 C2 13.5 18.5 Run 60” Dark gray to gray GNEISS, slightly weathered, hard,
Rec. 93% mod. to intensely fractured
RQD 53%
20 C3 18.5 23.5 Run 60” SAME
Rec. 77%
RQD 50%
25 Bottom of Hole 23.5 ft.
30
35
40
Nominal I.D. of Hollow Stem Auger 4.25 in. The subsurface information shown hereon was obtained for the Owner’s design and estimate purposes. It is made available to authorized users only that they may have access to the same information available to the Owner. It is presented in good faith, but is not intended as a substitute for investigations, interpretation or judgment of such authorized users. Approximate Change in Strata _____________ Inferred Change in Strata ----------------------
Nominal I.D. of Split Barrel Sampler 1 ⅜ in.
Weight/type of Hammer on Drive Pipe 300 lb.
Weight/type of Hammer on Split Barrel 140 lb. Safety
Drop of Hammer on Drive Pipe 24 in.
Drop of Hammer on Split Barrel 30 in.
Core Size N
Soil descriptions represent a field identification after D.M. Burmister \\edison\branch\Geotech\Connecticut\50018422 Baliwick Road\Boring Logs\B-1.docx unless otherwise noted.
Dewberry
ROUTE LOCAL NAME: Bailiwick Road Bridge Over Byram River - Bridge No. 05491 BORING NO. B-2
SECTION: Greenwich, CT FIELD BORING NO.
STATION: 105+26 OFFSET: 5 L REFERENCE LINE: Bailiwick Road N: 578946.153 E: 748217.022 GROUND ELEVATION: 132.5
BORING BY: Soiltesting, Inc. DATE STARTED: 8-10-2011 GROUND WATER ELEVATION
0 Hr. 125 24 Hr.
Date: 8-10-2011 Date: INSPECTOR: Joseph Yu DATE COMPLETED: 8-10-2011
DEPTH (ft)
CASING BLOWS
SAMPLE DEPTH NO.
Blows on Spoon REC. (in)
SOIL DESCRIPTION AND STRATIFICATION
Depth/ Elev.(ft) 0 / 6 6 / 12 12 / 18
AUGER 7.5 in. Asphalt
⇓ S-1 1 3 20 47 16” FILL: Dark brown c-f SAND, and(-) m-f Gravel, trace Silt
24 19
4/128.5
5
S-2 5 7 6 6 3” Gray brown c-m GRAVEL, some c-f Sand, trace Silt
15 16
Hard drilling from 7 to 9 ft., auger chatter
Auger refusal at 9 ft. 9/123.5
10 Bottom of Hole 9 ft.
15
20
25
30
35
40
Nominal I.D. of Hollow Stem Auger 4.25 in. The subsurface information shown hereon was obtained for the Owner’s design and estimate purposes. It is made available to authorized users only that they may have access to the same information available to the Owner. It is presented in good faith, but is not intended as a substitute for investigations, interpretation or judgment of such authorized users. Approximate Change in Strata _____________ Inferred Change in Strata ----------------------
Nominal I.D. of Split Barrel Sampler 1 ⅜ in.
Weight/type of Hammer on Drive Pipe 300 lb.
Weight/type of Hammer on Split Barrel 140 lb. Safety
Drop of Hammer on Drive Pipe 24 in.
Drop of Hammer on Split Barrel 30 in.
Core Size N
Soil descriptions represent a field identification after D.M. Burmister \\edison\branch\Geotech\Connecticut\50018422 Baliwick Road\Boring Logs\B-2.docx unless otherwise noted.
Dewberry
ROUTE LOCAL NAME: Bailiwick Road Bridge Over Byram River - Bridge No. 05491 BORING NO. B-3
SECTION: Greenwich, CT FIELD BORING NO.
STATION: 105+94 OFFSET: 4 R REFERENCE LINE: Bailiwick Road N: 578944.284 E: 748184.020 GROUND ELEVATION: 132.4
BORING BY: Soiltesting, Inc. DATE STARTED: 8-10-2011 GROUND WATER ELEVATION
0 Hr. N.R. 24 Hr.
Date: Date: INSPECTOR: Joseph Yu DATE COMPLETED: 8-10-2011
DEPTH (ft.)
CASING BLOWS
SAMPLE DEPTH NO.
Blows on Spoon REC. (in.)
SOIL DESCRIPTION AND STRATIFICATION
Depth/ Elev.(ft) 0 / 6 6 / 12 12 / 18
AUGER 7.5 in. Asphalt
⇓ S-1 1 3 29 58 20” FILL: Dark brown c-f SAND, some(+) m-f Gravel, trace Silt
32 12
4/128.4
5
S-2 5 6.9 27 28 17” Gray brown c-f SAND, some m-f Gravel, trace Silt
35 100/5
10 Gray brown c-f SAND, some m-f Gravel, trace Silt
S-3 10 10.3 80/3 Top of Rock 11/121.4
C1 11 16 Run 60” Dark gray to gray GNEISS, mod. to slightly weathered,
Rec. 97% mod. hard to hard, mod. to intensely fractured
RQD 50%
15
C2 16 21 Run 60” Dark gray to gray GNEISS, slightly weathered, hard,
Rec. 90% mod. to intensely fractured
RQD 83%
20
C3 21 26 Run 60” SAME
Rec. 97%
RQD 88%
25
Bottom of Hole 26 ft.
30
35
40
Nominal I.D. of Hollow Stem Auger 4.25 in. The subsurface information shown hereon was obtained for the Owner’s design and estimate purposes. It is made available to authorized users only that they may have access to the same information available to the Owner. It is presented in good faith, but is not intended as a substitute for investigations, interpretation or judgment of such authorized users. Approximate Change in Strata _____________ Inferred Change in Strata ----------------------
Nominal I.D. of Split Barrel Sampler 1 ⅜ in.
Weight/type of Hammer on Drive Pipe 300 lb.
Weight/type of Hammer on Split Barrel 140 lb. Safety
Drop of Hammer on Drive Pipe 24 in.
Drop of Hammer on Split Barrel 30 in.
Core Size N
Soil descriptions represent a field identification after D.M. Burmister \\edison\branch\Geotech\Connecticut\50018422 Baliwick Road\Boring Logs\B-3.docx unless otherwise noted.