J I M N E L S O N , I O W A D O T

MASSENA LATERAL BRIDGE SLIDE CASE STUDY

PRESENTATION OUTLINE

• Project overview

• Proposed replacement concept and details

• Construction

• Lessons learned

• Acknowledgements

PROJECT LOCATION

• IA 92 over Small Natural Stream, 1.0 mile west of Jct.

IA 148

PROJECT LOCATION

EXISTING STRUCTURE

• 40’ x 30’ Steel I-

beam

• Constructed 1930

• Reconstructed 1949

• Overlay 1968

• Retrofit rail 1992

• Overlay 1998

EXISTING STRUCTURE

• Structurally deficient

– sufficiency rating is

38.2

• Bridge is not

adequate for legal

loads – posted

“One truck at a

time.”

PROPOSED REPLACEMENT BRIDGE

• Pretensioned Prestressed Concrete Beam Bridge

MOBILITY IMPACTS

• Detour traffic for duration of construction

• 7 miles out of distance travel for detour

• AADT (2012) – 1,460 w/ 16% trucks

• User costs for 180 day detour

• Indirect $437,000

• Direct $15,000 (Co. Road Maint. & Detour Signing)

PROJECT STAGING AREA

UTAH DOT WANSHIP BRIDGE SLIDE

BRIDGE CONSTRUCTION VISUALIZATION

SEMI-INTEGRAL ABUTMENT

• Abutment Diaphragm Details – sheet number 14

SLIDING PAD

• Superstructure Details – sheet number 15

• Bonded PTFE surface on bearing pad detail

CONSTRUCTION

• Let April 16, 2013

• Winning bid $1.3 Million

• Traditional construction estimate $977,000

• Bridge unit cost - $112/SF

• Historic bridge unit cost - $85/SF

BID HIGHLIGHTS

• Removal of existing bridge - $60,000 (3x)

• H-piling - $167,200 (1.3x)

• Mobilization $100,000 (8%)

• Prefabricated bridge superstructure move $172,000

(1.7x)

CONSTRUCTION MILESTONES

• July 8 – Contractor moves in to site

• August 12 – Falsework completed

• September 6 – Bridge deck placement

• September 18 – Bridge test slide (roll)

• September 27 – Begin critical closure

• September 30 – Bridge slide

• October 6 – End critical closure

CRITICAL CLOSURE SCHEDULE

Activity 1 2 3 4 5 6 7 8 9

Start Critical Closure

Bridge Removal and Grading

Pile Driving

Revetment

Abutment Footing

Bridge slide

Precast wings

Granular Backfill

Bridge Barrier Rail

Approach paving

Barrier End Sections

Steel Guardrail

Longitudinal Grooving

Pavement Marking

Finish Critical Closure

Day

9/27/2013

10/6/2013

FALSEWORK

FALSEWORK

PPC BEAMS AND DECKING

SUPERSTRUCTURE COMPLETE

SUPERSTRUCTURE COMPLETE

PRE-TIED CAGE

BRIDGE DEMOLITION

H-PILE TEMPLATE

HP 14X117

ABUTMENT FOOTING

HIGH STRENGTH RODS

HIGH STRENGTH RODS

ROLLER

SLIDE JACK CONTROL

JACKING FRAME

SLIDE TRANSITION

START OF SLIDE

SLIDE

TRANSITION POINT

SLIDE NEARS COMPLETION

ROLLER REMOVAL

BRIDGE JACKING

ROLLER

SLIDE CHANNEL ON FALSEWORK

PRECAST WINGWALLS

DIAPHRAGM AND WING

FALSEWORK SEAT

SUBDRAIN

ABUTMENT BACKFILL

APPROACH AND BARRIER

APPROACH CONNECTION

CF JOINT

CONSTRUCTION TIME LAPSE

LESSONS LEARNED

• Designer/Owner

• Let ABC projects similar to steel bridges (fall letting)

• Incentive/Disincentive specification definitions

• Precast/CIP option for substructure units

• Be prepared to fully evaluate impact of contractor method changes

• Elimination of stainless steel sole plate

• Rolling in jacking pockets

• Do not allow re-use of laminated neoprene bearings

• Add a specification requiring falsework design engineer to

inspect and accept falsework construction

• ABC project design team time

DESIGN TEAM TIME

• Design Engineer 97 hours

• Detailer – 338 hours

• Check Engineer – 168 hours

• Total 603 hours

• Submittal Review Engineer – 137 hours • Structural steel – 2 hours

• Falsework plans and calculations

• Precast wingwalls

• Prefabricated superstructure move plans and calculations

• Prefabricated superstructure move procedures 9/25/13

LESSONS LEARNED

• Contractor

• Channel guide flexibility

• Communication method for slide technique

• Fewer splices in high strength threaded rod

• Contracts with subs

• Falsework design

MASSENA LATERAL BRIDGE SLIDE WEB SITE

ACKNOWLEDGEMENTS

• Designer – Iowa DOT

• Constructability Review – Michael Baker Corporation

• ABC Peer Exchange – Utah DOT

• ABC Detail Testing – Iowa State University

• Construction Administration – Iowa DOT

• Prime Contractor – Herberger Construction Co., Inc.

• Contractor’s Engineer – Tometich Engineering, Inc.

• Precast Wing Supplier – Cretex Concrete Products

• Precast Beam Supplier – Cretex Concrete Products

• HfL Grant – FHWA