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Assessing and constructing a cost effective bridge replacement christopher sichak, pe
1. Presentation for: 2012 NYSCHSA Summer Conference
August 28, 2012
By: Christopher Sichak, P.E.
2. Outline
• Introduction
• Existing Conditions
• Environmental Considerations
• Project Needs
• Development of Alternatives
• Project Costs
• Selection of Preferred Alternative
• Construction Phase
• Lessons Learned
• Summary
• Learning Assessment
• Questions
3. Introduction
Project Location
• NYSDOT Region 4, Orleans County, Town of Ridgeway
• Between Ridge Road (SR 104) and Oak Orchard River Road
• Oak Orchard River upstream of Waterport Pond (Lake Alice)
PROJECT
` LOCATION
4. Introduction
Project Team
Orleans County
Owner’s Group
• NYSDOT Region 4
• Town of Ridgeway
• Federal Highway Administration
Clark Patterson Lee / Dewberry-Goodkind, Inc.
Engineering
• Ravi Engineering & Land Surveying (survey, mapping, environmental, construction inspection)
• SJB, Empire Geo Services, Inc. (geotechnical, construction material testing)
• BME Associates (wetland delineation)
• R K Hite & Co., Inc. (right of way acquisition)
Ramsey Constructors, Inc. Material Suppliers:
• Clark Rigging (crane work)
• G & J Contracting (reinforcement installation)
• • Contech Construction Products, Inc.
Construction
Buffalo Barricade (detour signage)
• C & A Pavement Marking (pavement markings) • Lakelands Concrete Products, Inc.
• Villager Construction, Inc. (milling) • Pavilion Drainage Supply Co., Inc.
• Elderlee, Inc. (guide-rail and signs) • Suit-Kote
• Terry Tree (tree removal) • Hanson Aggregates
• Vellano Bros., Inc.
• MJ Dreher Trucking (trucking)
• Kistner Concrete Products, Inc.
• Farrell Landscaping (seeding)
• Keystone Builders Supply
• Fisher Associates (survey and ROW markers)
5. Introduction
• Bridge Constructed in 1930
• Steel Jack Arch Structure
• Two 40.7’ Spans (85’ total)
• 24’ curb-to-curb
• 27’ out-to-out
• No skew
• Reinforced
Concrete
Substructures
6. Existing Conditions
2006 Biennial Inspection
• 31 of the 50 (62%) rated elements had poor values (4 or lower)
• NYSDOT Condition Rating = 4.015, FHWA Sufficiency Rating = 39.9, General Rec. = 4
• Structurally Deficient (Condition < 5, significant maintenance to remain in service)
7. Existing Conditions
Safety Flags
• Condition presenting a clear and present danger to vehicular or
pedestrian traffic, but poses no danger of structural failure.
• Spalling of Concrete Parapets • Hole in deck near the pier
9. Existing Conditions
Geotechnical Investigations Boring Recovery RQD
B-1 81% 51%
• Shale bedrock below apparent fill soils
B-2 91% 28%
• RQD (Rock Quality Designation) RQD
Rock Mass
Quality
length of pieces exceeding 4”
____________________ <25% very poor
= x 100% 25-50% poor
length of core run 50-75% fair
75-90% good
•Bearing capacity of 8 tons/sf 90-100% excellent
10. Existing Conditions
Utilities
Electric (National Grid) Telephone (Verizon) Water (Town of Ridgeway)
o Relocate aerial o Relocate aerial o Coordinate geometry
facilities and street facilities along east with 8” Direct bored
light along east side side of the roadway watermain along east
of the roadway side of the roadway
12. Existing Conditions
Hydraulics
• 48 mile upstream length
• Initiates in Genesee County PROJECT
LOCATION
• 192 square miles drainage area
• Upstream flow controlled
50 Year Flood `
Model
Elevation (m)
Existing Structure 353.34
Replacement
353.27
Option 1
Replacement
353.37
Option 2
13. Environmental Considerations
Archeological Sensitive Area
SHPO Project Review
Application completed
2/9/09 detailing previous
Project Location
disturbance
SHPO concurrence with
2/24/09 previous disturbance
FHWA concurrence no
3/13/09 Phase I Cultural
Resources neccesary
14. Environmental Considerations
Environmental Screenings and Permitting
• USACOE Nationwide Permit #3
• NYSDEC Excavation and Fill in Navigable Waters
• NYSDEC Water Quality Certification
Endangered Species = Stream Restriction
• Longear Sunfish (Lepomis Megalotis)
• June 15 to September 15
15. Project Needs
Goals
• Replace existing structure within available funding limits
• Provide structural service life of 75 years
• Meet current standards
• Enhance safety
• Minimize stream disturbance in accordance with permits
16. Development of Alternatives
Conceptual Alternatives:
1. Rehabilitation
2. Single Span Multigirder Replacement:
a. Steel
b. Spread or Adjacent Prestressed Concrete Box Beam
c. Other Prestressed Concrete Shapes (AASHTO I, New England Bulb Tee)
3. Single Span Concrete Buried Structure
4. Two-Span Bridge Replacement (Steel or Concrete Superstructure)
5. Multi-Span Concrete Buried Structure
17. Development of Alternatives
Conceptual Alternatives:
1. Rehabilitation
2. Single Span Multigirder Replacement:
a. Steel
b. Spread or Adjacent Prestressed Concrete Box Beam
c. Other Prestressed Concrete Shapes (AASHTO I, New England Bulb Tee)
3. Single Span Concrete Buried Structure
4. Two-Span Bridge Replacement (Steel or Concrete Superstructure)
Dropped due to Hydraulic Characteristics
5. Multi-Span Concrete Buried Structure
18. Development of Alternatives
1. Rehabilitation
• Replace the superstructure
• Repair and reuse the existing substructures
• Retained existing features
would continue to
deteriorate
• Initial construction cost
• Anticipated future
maintenance costs
• Continued stream
obstruction from pier
19. Development of Alternatives
Conceptual Alternatives:
1. Rehabilitation
2. Single Span Multigirder Replacement:
a. Steel
b. Spread or Adjacent Prestressed Concrete Box Beam
c. Other Prestressed Concrete Shapes (AASHTO I, New England Bulb Tee)
Dropped due to Anticipated Costs
3. Single Span Concrete Buried Structure
20. Development of Alternatives
2. Adjacent Prestressed Concrete Box Beam Replacement
100’ (+/-)
Proposed Elevation
• Lower initial construction cost than steel multigirder
• deck forming and thickness
• Tall Concrete Abutments and Wingwalls with spread footings on bedrock (25’ – 30’)
21. Development of Alternatives
3. Single Span Concrete Buried Structure
• Lower maintenance costs • Arch:
o Absence of features o Geometry fits well with
requiring maintenance: site topography
Joints o Structurally sound and
Bearings efficient shape
Deck o Most economical
Primary Members foundation size
• Lower construction costs
o Limited field construction
(precast)
o Limited field specialty work
22. Development of Alternatives
3. Single Span Concrete Buried Structure (Precast Arch)
77’-9”
21’-10”
Proposed Elevation
• Detailed as a precast structure
o Twin leaf structure, headwalls, and wingwalls
o E78T/0: Contech BEBO (77’ -9” Span x 21’ –10” Rise)
23. Development of Alternatives
•LRFD Specifications mandated for bridge design by October 1, 2007
EI 05-003
•Exception: LRFD implementation for design of buried structures in 2010
EI 07-014
EI 07-030 •Release of 2007 (Metric and US) and 2008 (US) LRFD Specifications
EI 08 -042
•Release of 2010 US Customary LRFD Specifications
EI 10-013 •Implementation for buried structures if the project’s preliminary
engineering design phase begins after October 1, 2010
Design Criteria Standard Value Existing Value Proposed Value
Structural HL-93 and NYS Design Permit Vehicle (LRFD Replacement Min.)
MS-23 (AASHTO Replacement Min.) N/A MS-23
Capacity MS-18 (AASHTO Rehabilitation Min.)
24. Development of Alternatives
Maintenance and Protection of Traffic
• Traffic maintained via offsite detour
• NYSDOT Highway Work Permit (PERM 33)
Right of Way
• 66’ ROW width
• Single property owner (Erie Boulevard Hydropower) adjacent to structure
• Temporary easements taken at the four corners of the bridge
o Constructing wingwalls
o Placing stone filling
• Donation streamlined the ROW process and minimized project costs
26. Selection of Preferred Alternative
Preferred Alternative: Precast Concrete Arch Replacement
• Lowest Initial Construction Cost
• Precast Components
o Quality Control During Fabrication
o Expedited Installation
o Minimal Environmental Impacts
• Lowest Maintenance Costs
• Aesthetics - recreational area during summer months
oForm liner considered but dropped due to:
Cost (not federally reimbursable)
Rural Location
27. Selection of Preferred Alternative
Preferred Alternative: Precast Concrete Arch Replacement
Bid, Letting, and Award
• Advertised on April 14, 2010
o Delayed due to federal fund availability
o 75 calendar days from anticipated NTP to completion date
32 calendar days prior to stream restriction
51 calendar days post stream restriction
• Bid opening on May 5, 2010
o Low Bidder: Ramsey Constructor's, Inc. (4 bidders)
o 92% Engineers Estimate
29. Construction Phase
Precast Arch Concrete Footing
Placement
Completed July 30, 2010
30. Construction Phase
Precast Concrete
Shop Drawings
Submitted July 2, 2010
Approvals:
Foundation Layout: July 12, 2010
Arch Units: July 27, 2010
Wingwalls/Headwalls: August 11, 2010
50. Lessons Learned
• Appropriate Geotechnical Explorations
• Pay attention to surrounding existing features
• Permitting / Stream Restrictions
• May impact the preferred alternative
• Constructability
• Utilize input from others to understand the process
52. Learning Assessment
Q: What NYSDOT bridge rating typically constitutes a “poor” rating?:
a) 5: Minor deterioration, but functioning as originally designed.
b) 4: Between a 5 and a 3 rating.
c) 3: Serious deterioration, or not functioning as originally designed.
d) 2: Between a 3 and a 1 rating.
e) 1: Totally deteriorated, or in failed condition.
A: b) 4
53. Learning Assessment
Q: Which statement(s) is/are true of a structurally deficient bridge:
The bridge
a) doesn't meet current standards for managing traffic volumes.
b) has a condition rating < 5.
c) has narrow lanes, no shoulders, or low clearances.
d) requires significant maintenance to remain in service.
e) is unsafe or likely to collapse.
A: b) has a condition rating < 5
and
d) requires significant maintenance to remain in service
54. Learning Assessment
Q: Which statement is true of a Safety Flag:
a) Reports a condition presenting a clear and present danger to vehicular or
pedestrian traffic, but poses no danger of structural failure.
b) Reports a potentially hazardous structural condition, which if left unattended
could become a clear and present danger before the next scheduled inspection.
c) Reports the failure or potential failure of a primary structural component that is
likely to occur before the next schedule biennial inspection.
A: a) Reports a condition presenting a clear and present danger to vehicular or
pedestrian traffic, but poses no danger of structural failure.
55. Learning Assessment
Q: In geotechnical exploration, what does RQD stand for?
A: Rock Quality Designation
56. Learning Assessment
Q: (True/False) Meeting the freeboard recommendation is the primary
concern on all bridge replacement projects over water.
A: False, while true for most projects, other considerations such as
recurring scour or stream obstacles (pier) need to be taken into
consideration.
57. Learning Assessment
Q: (True/False) Structural design criteria currently requires the use of
AASHTO Standard Specifications (Allowable Stress Design) for Buried
Structures.
A: False, LRFD specifications are required if the project’s preliminary
engineering design phase began after October 1, 2010.
58. Learning Assessment
Q: Identify four conventional bridge elements not contained as part of
precast concrete buried structures which account for lower
maintenance costs.
A: 1. Joints
2. Bearings
3. Deck
4. Conventional Primary Members
59. Learning Assessment
Q: What benefits can be realized during the construction of a precast
concrete buried structure resulting in minimized construction costs
and an enhanced finished product?
A: 1. Increased quality control during fabrication.
2. Expedited installation (lack of forming, pouring, cure times)
3. Minimization of environmental impacts.
60. Learning Assessment
Q: What is the name Contech gives to the mechanism which connects the
geotextile “tabs” cast into the back face of the MSE style walls and the
Tesar geotextile within the backfill zone?
A: Bodkin Bar
61. Learning Assessment
Q: (True/False) It is possible to construct a bridge over a stream with a
restriction during the prime construction season.
A: True.
