innovative precast bridge system
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Simple, Economic and Fast Solution for Bridge substructures.
Innovative Precast System
For Short Spans and Low Volume Bridges
Year Built : 1950
Primary Owner : Town
Steel Stringers
Timber Deck
Span Length : 30 feet
Out to Out Width : 23.6 feet
Skew Angle : 30 Degrees
Abutment Height : 14 Feet
AADT : 57
Posted for 5 Tons
Founded on Spread Footers
Bridge Data
Innovative Precast System
For Short Spans and Low Volume Bridges
Case Study in NY
Existing Conditions
Innovative Precast System
For Short Spans and Low Volume Bridges
3
Bridge Replacement Alternatives
Four Sided Structure
Three Sided Structure ( Box or Arch)
Integral Abutment with Prestressed Beams Superstructure
Non Conventional System
Innovative Precast System
For Short Spans and Low Volume Bridges
Types of Concrete Abutments
Cantilever Abutments
Integral Abutments
Abutments Founded on Piles
Non Conventional System
Innovative Precast System
For Short Spans and Low Volume Bridges
- Concrete Gravity Abutments include reinforced and non reinforced types
- Integral abutments are stub abutment with one line of piles
Abutment founded on piles are gravity on piles
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Cantilever Abutments
Abutment Stem
Abutment Backwall
Abutment Footings
Design Forces
Main Components
Earth Lateral Pressure
Loads From Superstructure
Bearing Capacity
Innovative Precast System
For Short Spans and Low Volume Bridges
How it Works ?
Factors Affect the Footing Dimensions:
Toe and Heel Widths are Determined by The Sliding and Overturning Forces
The Footing Area is Determined by the Bearing Capacity Constraints
The Footing Thickness and Reinforcement are
Determined by The
Base Pressure
(Shear and Flexure)
Innovative Precast System
For Short Spans and Low Volume Bridges
Factors Affect the Stem Dimensions:
Stem Thickness is Determined by Flexural forces Resulted from Earth Pressure
Reinforcement is Determined By the Flexural Forces
Bridge Seat Requirements May Determine the Thickness of the Stem Which Results in Excessive Concrete Volume
Innovative Precast System
For Short Spans and Low Volume Bridges
8
Cantilever Abutments
Conventional System, Easy To Construct and Design
Suitable For Most Soil Conditions (Rock or Shale )
Can be Used With Any Skew
Cons
Pros
Not Suitable For Poor Soils
Requires Large Amount of Concrete
Requires Large Quantity of Reinforcement
Requires Large Volume of Excavation
Requires a Deck Joint
Innovative Precast System
For Short Spans and Low Volume Bridges
Integral Abutments
Abutment Stem
Deep Foundations (Piles)
Main Components
Design Forces
Earth Lateral Pressure
Loads From Superstructure
End Bearing Capacity or Skin Friction Capacity
Innovative Precast System
For Short Spans and Low Volume Bridges
How it works ?
Factors Affect the Abutment Dimensions:
Stem Thickness is Determined by Flexural forces Resulted from Earth Pressure
Reinforcement is Determined By the Flexural Forces
Bridge Seat Requirements May Determine the Thickness of the Stem Which Results in Excessive Concrete Volume
Innovative Precast System
For Short Spans and Low Volume Bridges
Integral Abutments
NYSDOT Preferred Abutment Type
Jointless Bridge System
Less Concrete and Reinforcement Than the Gravity Abutments
Fast Construction Time Compared to Gravity Abutment
Cons
Pros
Not Suitable For All Soil Conditions
Not Suitable For Large Skews
Requires Deep Foundation
Costs More Than Gravity Abutments
Innovative Precast System
For Short Spans and Low Volume Bridges
Precast Abutment System
Pre-Cast Concrete Cap
Pre-Cast Concrete Lagging
Pre-Cast Concrete Footings
H-Piles Embedded In Concrete Footings
Design Forces
Main Components
Earth Lateral Pressure
Loads From Superstructure
Soil Parameters
Innovative Precast System
For Short Spans and Low Volume Bridges
How It Works
The System Consist of The Following:
Pre-Cast Lagging: Designed to Retain The Soil and Resist Lateral Forces from Soil
H-Piles: Designed to Carry the Cap Beam Which Carries The Super Structure
Precast Footings: Designed to Distribute the Load to The Bearing Stratum
Mechanical Couplers: Connects The Units Together
Innovative Precast System
For Short Spans and Low Volume Bridges
Design Forces
Factors Affect the Footing Dimensions:
Toe and Heel Dimensions are Determined by The Sliding and Overturning Forces
The Footing Area is Determined by the Bearing Capacity Constraints
The Footing Thickness and Reinforcement are Determined by The Base Pressure (Shear and Flexure)
Innovative Precast System
For Short Spans and Low Volume Bridges
Precast Abutment System
Simple and Flexible Design
Easy To Handle and Install
Small Sections Compared to
Conventional Design
Fast Construction Time
Economic Design
Concrete Cap To Accommodate Bridge Seat Requirements
Can Be Installed with Mid Size Excavator
Cons
Pros
Aesthetics
Innovative Precast System
For Short Spans and Low Volume Bridges
Bridge beams: $38,566 includes all of your engineering charges to us
Abutment units: $22,633
Lagging pieces: $ 6,951
Total for all pieces: $ 68,150
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Pre-Cast Abutment System
Pre-Stress Pre-Cast Beams
The Preferred Alternative
Innovative Precast System
For Short Spans and Low Volume Bridges
Construction Phase
Innovative Precast System
For Short Spans and Low Volume Bridges
Questions ?
Innovative Precast System
For Short Spans and Low Volume Bridges