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Bridge Falsework Forum-
Welcome & Introduction
Dolores Valls, P.E.
Deputy Division Chief
Offices of Structure Construction
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Welcome & Introduction
Introduction of Key Participants Purpose of Forum
Notes & Action Items
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Introductions- Key Participants
Facilitator Mike Halverson Falsework Manager John Babcock
OSC F/W Senior Engineers: North = John Walters
South = Ken Burkle
OSC F/W Technical Team
CT/Industry Joint F/W Advisory Team
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Falsework Forum - Purpose
High Risk F/W Operation: Contractors, OSC, public
Joint Responsibility for public safety
High profile incident new definition
Time to discuss:
Best Management Practices
Revised Specifications?
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Falsework Forum Notes
Action Items will be captured All notes will be posted on Internet
http://www.dot.ca.gov/hq/esc/construction/construc.htm
Division of Engineering Services
Structure Construction
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PROGRESSION OF MEETINGS
RELATED TO FALSEWORK
STABILITY
(John Babcock)
INTERNAL FALSEWORK TEAM
JOINT CALTRANS/INDUSTRY
FALSEWORK ADVISORY TEAM
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Bridge Falsework Forum
Series of three meetings to addressfalsework stability
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Bridge Falsework Forum
Offices of Structure Construction TechnicalTeam, Falsework
Issues Identified
Solutions suggested
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Bridge Falsework Forum
Joint Caltrans / Industry FalseworkAdvisory Team Issues Identified
Solutions recommended
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INTRODUCTIONS
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Agenda REGISTRATION
FORUM INTRODUCTION (Dolores Valls)
INTRODUCTIONS
PROGRESSION OF MEETINGS (John Babcock)
BACKGROUND
ADVISORY TEAM RECOMMENDATIONS
FALSEWORK STABILITY TRAFFIC OPENING REQUIREMENTS
COMMUNICATION/PARTNERING/FALSEWORK DESIGN
PLANS
FALSEWORK ENGINEER PRESENCES AND APPROVALS BEST PRACTICES (Internal by Contractor)
REWRITE FALSEWORK MANUAL, BRIDGE
CONSTRUCTION MEMOS, SPECIFICATIONS
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Agenda
ADVISORY TEAM RECOMMENDATIONSWINCHES FOR FALSEWORK REMOVAL
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FALSEWORK SUBMITTALS3 0 4
1 0 5
1 7 4
9 5
4 2
9 41 0 4
4 4
1 0 8
1 2 6
6 0
0
5 0
1 0 0
1 5 0
2 0 0
2 5 0
3 0 0
3 5 0
1 9 9 7 1 9 9 8 1 9 9 9 2 0 0 0 2 0 0 1 2 0 0 2 2 0 0 3 2 0 0 4 2 0 0 5 2 0 0 6 2 0 0 7
Year
Submittals
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MAJOR FALSEWORKINCIDENTS
1 1
2
3
0 0
3
1
0
3
1
0
2
4
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Year
MajorIncident
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FALSEWORK STABILITY
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FALSEWORK STABILITY
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FALSEWORK STABILITY
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FALSEWORK STABILITY
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CASE 1
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Falsework Elevation View
121 123122
Not attached
per plan
Contractor grading Bent at time of incident.Contractor grading Bent at time of incident.
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Falsework Bent Elevation
W24 X 131
CenterlineBent 123
Cable Bracing
Cripple Cap
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CASE 1
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CASE 2
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CASE 2
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CASE 2
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CASE 3
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CASE 3
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CASE 3
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CASE 3
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CASE 3
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LESSONS LEARNED
Stability measures must be in place at all times Multi-tiered systems require special attention Dont adjust falsework over or adjacent to
traffic
34
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DONT ADJUST
FALSEWORK OVER OR
ADJACENT TO TRAFFIC
Contract Special Provisions Maintaining Traffic
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HOW DO WE MAINTAIN FALSEWORKSTABILITY?
Or
WHAT IS IT THAT CAUSESFALSEWORK TO BECOME UNSTABLE?
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ADVISORY TEAM
RECOMMENDATIONS -
STABILITY
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1. Traffic Opening requirements
1.1 Independently stable/ stand aloneframes
1.2 Connection criteria
1.3 Customary to increase load withincreased risk
1.4 Continuity between structure columns
1.5 Implementation:
1.5.1 Falsework Manual
1.5.2 Specifications
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2. Communication/Partnering/Falsework Design Plans
2.1 Require meetings at criticalbenchmarks
2.1.1 Erection
2.1.2 Grading
2.1.3 Removal
2.1.4 Prior to opening to traffic (forfalsework over traffic)
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2. Communication/Partnering/Falsework Design Plans
2.2 Erection and Removal Plans2.2.1 General at time of falsework plan
submittal
2.2.2 Detailed at pre-activity meeting
2.3 Implementation
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3. Falsework Engineer of RecordPresence and Approvals
3.1 At Critical benchmarks3.1.1 Certify prior to traffic opening (for
falsework over traffic)
3.1.2 Onsite during grading operations
3.1.3 Progressive stages of construction
3.2 Implementation
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4. Best Practices(Internal by Contractor)
4.1 Training4.2 Company Certification
4.3 Implementation
5 R i F l k M l
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5. Rewrite Falsework Manual,
Bridge Construction Memos,Specifications
5.1 Longitudinal Stability Analysis
5.2 Friction Transfer Capacity (FTC)
Allowance
5.3 Testing and use of clamps
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WINCHES FOR
FALSEWORK
REMOVAL
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WINCHES FOR FALSEWORK REMOVAL
Traffic window limitations
Operation cannot be reasonably doneotherwise
Does not encroach upon the vertical
and horizontal traffic clearances
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WINCHES FOR FALSEWORK REMOVAL
Will not cause a traffic disruptionWork is performed at night with a
closure
Load is static to structure soffit
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ADVISORY TEAM RECOMMENDATIONS
Winches for Falsework Removal
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ADVISORY TEAM RECOMMENDATIONS
1. Redundant systems are used
1.1 Use High Strength rods or strands
and winches
1.2 High strength rods or strands1.2.1 Requires redundant system
1.2.2 Requires use of new strand
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ADVISORY TEAM RECOMMENDATIONS
1.3 Winches only
1.3.1 Safety factor (5:1)
1.3.2 Certification
1.4 Inspection of critical elements (NDT)
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ADVISORY TEAM RECOMMENDATIONS
2. Implementation
2.1 Provide additional direction
2.2 Update Falsework Manual
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Discussion
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Adjourn
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