Presented to AASHTO T-8, June 17, 2013

AASHTO AS 13-0024 Support for the HSCOBS Technical Committee on Moveable Bridges (T-8) in a Technical Advisory Role for Specification Updates – Span Lock Design Study

By James M. Phillips III, PE URS

PRESENTATION OUTLINE

Purpose of Study Work Plan Project Status Report

PURPOSE OF STUDY

Advance the industry's knowledge of span lock behavior

Provide information and recommendations to T-8 Improve the general practice of span lock design Improve the provisions of the AASHTO LRFD

Movable Highway Bridge Design Specifications with regard to design of span locks

PURPOSE OF STUDY

Determine appropriate impact (dynamic load allowance) factors for use in design and evaluation of span locks

Quantify the effects of operating clearances and wear on span lock loading and dynamics

Quantify the effects of bascule span deflection and end rotation on span locks

WORK PLAN

Research Span Lock Materials

FEA Analysis Field Testing Verification and Evaluation Report

PROJECT STATUS REPORT

Screening Evaluation Completed initial screening of FDOT double-leaf

bascule bridges Identified viable candidates for field testing

Hillsborough Avenue Bridge, Tampa, FL, FDOT D7 Sunrise Boulevard Bridge, Ft. Lauderdale, FL, FDOT D4 US41 / Hatchett Creek, Venice, FL, FDOT D1

Hillsborough Avenue Bridge, Tampa, FL (FDOT District 7)

Hillsborough Avenue Bridge, Tampa, FL (FDOT District 7)

ANALYSIS – Hillsborough Ave Bridge

Global Model of Bascule Girders, Floor Beams and Span Lock Assembly

ANALYSIS – Hillsborough Ave Bridge

Expanded View of Span Lock

ANALYSIS – Hillsborough Ave Bridge

Plain Bending Stress

ANALYSIS – Hillsborough Ave Bridge

Plain Bending Stress in Lock Bar

ANALYSIS – Hillsborough Ave Bridge

Contact Stress in Guide and Receiver Shoes

FIELD INSTRUMENTATION

Met with FDOT Materials Laboratory Staff Developed Instrumentation Fixture Sketch Met with FDOT Staff at Hillsborough Avenue

Bridge to plan instrumentation and traffic control

Instrumentation Fixture Sketch

Next Steps

FDOT is constructing instrumentation fixture Instrumentation and testing of Hillsborough Ave

preliminarily scheduled for July, 2013

Florida Department of Transportation

presents

Bascule Bridge Lightweight Solid Deck

Retrofit Research Project

Aluminum Orthotropic Deck Research Topics Meeting

FIU Engineering Center - Miami, Florida

May 30, 2013

Screening Report Overview

Purpose: Identify Potential Alternative Lightweight Solid Deck Systems to Replace Steel Open Grid Deck on Typical Florida Bascule Bridges

Value Engineering (VE) Comparison Four (4) Primary Deck Systems Evaluated

SPS Deck Aluminum Orthotropic Deck (5-inch Deep) FRP Composite Deck (Incl. Numerous Types) UHPC Waffle Slab Deck Others Dismissed Due to Excessive Weight

Screening Report Overview

Screening Report Overview

Approx. 40 Different Evaluation Criteria Incl. Weight Cost Functionality and Safety Maintenance Service-Life and Durability Constructability Other Risks

Scoring 1-9 Importance Factor Multiplier Steel Open Grid Baseline (Score 5 Ea. Criteria)

Screening Report Overview

Screening Report Overview Deck System Overall Score

Steel Open Grid 500

SPS 492

Aluminum Orthotropic 557

FRP Composite 496

UHPC Waffle Slab 502

All evaluated Lightweight Solid Deck Alternatives are viable candidates to replace Steel Open Grid Deck on typical Florida Bascule Bridges. However, Aluminum Orthotropic Deck scored well above Steel Open Grid Deck and other Lightweight Solid Deck Alternatives and thus considered superior.

Aluminum Orthotropic Deck

Advantages: Functionality and Safety Weight Neutral Solution (21 psf) Durability and Service Life Robust Design (Meets all AASHTO Limit States) High Stiffness (L/3000) Corrosion Resistance Improved Strength and Fatigue Resistance with

Friction Stir Welding

Configuration Adaptable to Different Bascule Leaf Configurations Minimal Bridge Modifications Accommodate Maintenance of Traffic

Aluminum Orthotropic Deck

Advantages (Cont’d): Available AASHTO LRFD Design Specifications Material Familiarity and Predictability Previous Testing and Research Derivative of SAPA R-Section (Reynolds Alumadeck) FHWA/VDOT/Virginia Tech Testing Program Little Buffalo Creek Bridge (15+ Years Service)

Material Availability/Product Support Aluminum Industry (SAPA)

Aluminum Orthotropic Deck

Disadvantages: High Initial Cost (~$150/sf) New (Derivative) Product Coefficient of Thermal Expansion 12.8x10-6/F (Alum.) vs. 6.5x10-6/F (Steel) Requires Slip Connections Requires Expansion Joints

Wearing Surface (Periodic Replacement) Galvanic Corrosion (Mitigation) Blind-Type Fasteners Patented Product

Research and Testing

Previous Testing (8-inch Deep SAPA R-Section) Differences with 5-inch Deep Deck (Geometry,

Details, Application) Test Panels to be Supplied by Others Testing Performed by FIU Testing Oversight, Evaluation and/or Review by:

FDOT Structures Research Center FDOT District 4 FDOT Central Office URS Others

Research and Testing

Purpose: Demonstrate Panel Performance and Behavior at

AASHTO LRFD Limit States (Strength I, Strength II, Service I (Deflection) and Fatigue (Infinite Life)

Verify Panel Wheel Load Distribution Demonstrate Ability of Panel-Stringer Connections to

Accommodate Thermal/Flexural Movements Demonstrate Ability of Fastener Locking Devices to

Resist Loosening Evaluate Wearing Surface Performance Demonstrate Construction Means and Methods Demonstrate In-service Performance Demonstrate Panel Ultimate Strength