Schematic Design of an Accelerated Bridge Construction Project Michael P. Culmo, P.E. Vice President of Transportation and Structures CME Associates, Inc., East Hartford, CT

Reference Manual Use the Connections Details Manual –Type study concept –Select details from various states

Case Scenario 4 lane bridge over an expressway Existing bridge has deteriorated beyond repair Heavy traffic on both roadways There is a short but undesirable detour

Public Involvement Public hearing heldPublic hearing held Businesses do not want a long construction process with stage constructionBusinesses do not want a long construction process with stage construction Businesses are not keen about a detourBusinesses are not keen about a detour They will accept a short term closure with the detourThey will accept a short term closure with the detour –As opposed to a long term staged project

Design Approach Options Build a temporary bridge to speed up construction of the new bridge –$$$$ –Not that fast Use multi-stage construction –Very long construction –Will require long term lane closures Establish the detour and accelerate the bridge construction to less than 30 days

Existing Bridge

Deck Joints Low Clearance Existing bridge issues

Proposed Bridge Type After a formal type study, the owner opted with the following structure criteria –Use NEXT Beams to accelerate construction Design as simple span for Dead Load and continuous spans for Live Load –Increase clearance by raising approach grades (3’) –Use integral abutments (no deck joints) –Composite concrete deck –Membrane waterproofing and Bituminous wearing surface –Use Precast Rail System (Vermont/NH system)

Substructures Push abutments back to top of slopePush abutments back to top of slope –Minimize wingwall requirements –Use integral abutments with flying wings –Eliminate spray attack on abutments Place abutments in a different footprint than the existingPlace abutments in a different footprint than the existing –facilitates construction Use open frame pier bent on spread footingsUse open frame pier bent on spread footings

Proposed Bridge Move abutment away from roadway No Deck jointsIncrease vertical clearance

Bridge Section

Beam Design Preliminary Beam Sizing –Use PCI NEXT Beam Standards

Beam Design LLDF

Beam Design AASHTO LL Distribution Factor – Type K Moment Shear

Beam Design AASHTO LLDF Type H Moment Shear

Beam Design Structure TypeHK LLDF Moment LLDF Shear

How to select details FHWA manual “Connection details for prefabricated bridge elements and systems” 1.Review Chapter 1 Investigate connection types, materials, tolerances 2. Search applicable sections of other chapters for details

Section 1.4 Typical Connection Types After reviewing chapter 1, the owner chose the following connection types –Grouted reinforcing splice couplers Quick, proven system Can develop full bar strength Simplifies the design process (similar to CIP) –Grouted Voids Easy for simple connections –Concrete Closure pours between precast elements Use for a limited number of connections (slower)

Grouted Reinforcing Splice Connectors Emulates a reinforcing steel lap splice Multiple companies – non-proprietary Used in precast parking garages and stadiums and bridges

Grouted Reinforcing Splice Connectors Emulates a reinforcing steel lap splice Multiple companies – non- proprietary Used in precast parking garages and stadiums and bridges Time Lapse Video on Youtube TM –Search “Georgia Pier Construction” Installation Video on Youtube TM Search “Georgia Pier Construction” Installation video

Footing to Sub-grade Connection

Footing Details

Footing to Column Connection

Column to Cap Connection

Completed Pier Footing to subgrade connection Column to footing connection Column to cap connection

Abutment Details Integral Abutment to precast piles –Section Precast Integral Abutment to Piles Detail developed by Maine DOT –Used on three different bridges

Abutment to Pile Connection

Abutment To Wingwall Connection

Approach Slab Connection

Completed Abutment Pile to cap connection Approach slab connection Flying Wingwall connection Abutment cap connection

Deck Design with Next Beam Design as a conventional cast in place deck – Use max stem spacing for design (5.0 feet) – Design overhang from outside stem (2.53 feet)

Parapet Connection

Superstructure to Integral Abutment Connection Use a similar detail at the pier

Completed Bridge Precast Integral Abutment Composite Deck Membrane waterproofing with bit. Wearing surface Precast Pier Precast Parapet

Final Bridge

Estimated Construction Schedule

Costs Typical New Bridge (Cost=$200/sf) = $1,920,000 Premium for ABC (assume 20%) = $384,000 Temporary Bridge (Cost=$60/sf) = ($576,000) Net Savings = $192,000 Note: These prices will vary by region

Ways to reduce bid prices with ABC Standardization Programmatic (not one of a kind) Reduced project site costs (trailers, etc.) Reduced Maintenance of Traffic Costs Inflation Other Non- Bid Savings with ABC Fewer Police Details Reduced Resident Engineering time User Costs Plus: $$ Can be significant Minus: $$ Not in the budget Other Cost Savings

Quality Florida has had very good success with precast piers in very harsh environments Precast concrete beams require no maintenance Integral abutments eliminate deck joints

Old Adage By elimination of temporary bridges or costly stage construction schemes, you CAN have all three Rapid Construction High Quality Low Cost You can only have any two

Conclusions It is possible to build a complete bridge in 30 days (or less) The FHWA manual provides a starting point for a complete bridge prefabrication project You do not need to sacrifice quality to get rapid construction You can save money on an accelerated bridge project by: –Reducing construction time –Eliminate temporary bridges or staging

Questions