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Short Span Steel Bridge Alliance. North Central States Bridge Consortium, Sioux Falls, SD David Stoddard Applications Engineer, SSAB Americas Contact Information. Objectives. Objective of owners & bridge engineers: More efficient & economical short span bridges
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Short Span Steel Bridge Alliance North Central States Bridge Consortium, Sioux Falls, SD David Stoddard Applications Engineer, SSAB Americas Contact Information
Objectives • Objective of owners & bridge engineers: • More efficient & economical short span bridges • Identify design solutions quickly • Objective of presentations today: • Provide bridge engineers & owners with resources to consider short span steel bridge solutions in design comparisons • Demonstrate steel can be competitive
Outline of Today’s Presentation • Why steel for bridges? • Short Span Steel Bridge Alliance (SSSBA) • Interactive Short Span Steel Bridge Website • Short Span Standards • eSPAN140: Overview • Economics Case Study: Steel vs. Concrete • eSPAN140: Bridges Constructed • Innovative Designs • Training & Education
Why steel for bridges? First Cost/Economical 25% less than concrete with cost-efficient design, fabrication, and construction practices Up to 33% less with new innovative designs concepts Modular Light weight, prefabricated options, easy to construct Standardized plans Durable Highly resistant to natural disasters (seismic) Long life cycle (weathering steel & galvanized options) Sustainable 100% recycled Recycled content (steel has over 90% recycled rate)
Short Span Steel Bridge Alliance Program officially started September 2007 Objective – make steel the material of choice for short span steel bridges. Short span steel bridges have spans up to 140ft First North American industry-wide effort to provide education and design support for short span steel bridges.
Providing Economical Steel Solutions to 140 Feet (40 Meters) 18 - 40 meters 40-100 feet 12-30 meters
Fasteners Coaters Producers Service Centers Fabricators Contractors Design Firms Trade Organizations Universities Bridge Owners
Target Audience (Bridge Owners & Designers) • United States • 3,000 USA County Engineers (Local/Regional Officials) • 50+ USA State DOT • Federal Highway Officials • Consultants, Designers, Universities, etc. • Canada • Ministers of Transportation (MTOs) • Mexico / Latin America • Municipalities
What do we do? Education (webinars, workshops, forums, conferences) Technical Resources (standards, guidelines, best practices) Case Studies (economics: steel is cost-effective) Simple Design Tools (eSPAN140) Answer Questions (Bridge Technology Center) Access to Industry Partners (industry contact list) All FREE for bridge owners & designers
Website • eSPAN140 Web-based Design Tool • Bridge Technology Center • Technical Design Resources • Catalog of Short Span Steel Solutions • Project Case Studies • Video &Photo Gallery • News Updates & Social Media (Twitter / LinkedIn / Facebook) • Email Newsletter (sign-up to receive it) • Calendar of Industry Events www.ShortSpanSteelBridges.org
Membership – Join Today! • Free to join for limited time • See www.ShortSpanSteelBridges.org more a list of benefits • Contact Dan Snyder, Director of the SSSBA • dsnyder@steel.org • 301-367-6179
Standard Short Span Steel Bridge Designs Goals & Design Methods
Standards for Short Span Steel Bridge Designs • Goals: • Economically competitive • Expedite & economize the design process • Simple repetitive details & member sizes. • Bridge Design Parameters: • Span lengths: 40 feet to 140 feet (5-foot increments) • 12 meters to 42 meters (1.5-meter increments) • Girder spacing: 6 feet, 7.5 feet, 9 feet and 10.5 feet • 1.829 meters, 2.286 meters, 2.743 meters, 3.200 meters • Homogeneous & Hybrid plate girders with limited plate sizes • Limited Depth & Lightest Weight Rolled Beam Sections • Selective cross-frame placement/design (AASHTO/NSBA)
Free Online Design Tool for Short Span Steel Bridges Developed by the Short Span Steel Bridge Alliance http://www.espan140.com/
eSPAN140 • eSPAN140 is an easy-to-use and free resource for bridge engineers & owners. • In 3 easy steps, multiple steel solutions are recommended!
Step 3: Customized Solutions Book is Provided (pdf) • Standard Design and Details of Short Span Steel Bridges Solutions • Rolled Beam Recommendations • Plate Girder Recommendations • Standard Design and Details of Corrugated Steel Pipe and Structural Plate Solutions • Manufacturer’s Steel Solutions (SSSBA Partners) • Customized Solutions from Members of the SSSBA • Durability Solutions (SSSBA Partners) • Galvanized & Paint • Weathering Steel • Additional Contact Information
Design Example • Sample plate girder (homogeneous) elevation:
Design Example • Sample plate girder (homogeneous) data:
Design Example • Sample rolled beam (lightest weight) elevation:
Design Example • Sample rolled beam (lightest weight) data:
Design Example • Typical girder elevation:
Design Example • Typical stiffener details:
Design Example • Typical diaphragm details:
Design Example • Typical section details:
Design Example • Typical bearing details:
Durability Solutions • Weathering, galvanized, and painted steel
Galvanizing Facts (provided by AGA) • Advancements have led to more economical product • Misconception that it is more expensive than paint • Often less expensive than 2- & 3- coat high performance systems • Galvanizing prices held steady over the last 15 years • Galvanizing’s maintenance-free longevity (70 years of more in atmospheric exposure) often means initial cost is final cost
The Bridge Technology Center • Free resource available to bridge owners and designers with questions related to: • Standard design and details of short span bridges (plate & rolled beam) • Standard design and details of corrugated steel pipe and structural plate.
Short Span Steel Bridge Case Study Steel vs. Concrete Audrain County, MO
Case Study Bridges: Side-by-Side Comparison Audrain County, MO Bridge 411 Built 2012 Steel 4 Girders 47.5 ft. Span (14.478 m) 24 ft. Roadway Width (7.315 m) 2 ft. Structural Depth (0.610 m) No Skew Steel Concrete Audrain County, MO Bridge 336 Built 2012 Precast 6 Hollowcore Slab Girders • 50.5 ft. Span (15.392 m) • 24 ft. Roadway Width (7.315 m) 2 ft. Structural Depth (0.610 m) 20o Skew
Case Study Bridges: Side-by-Side Comparison Total Cost of Structure Steel Concrete • 19.3% Total Bridge Cost Savings with Steel Total Bridge Costs Material = $41,764 Labor = $24,125 Equipment = $21,521 Guard Rail = $ 7,895 Rock = $ 8,302 Engineering = $ 8,246 TOTAL = $111,853 ($97.48 / sq. ft.) Total Bridge Costs Material = $67,450 Labor = $26,110 Equipment = $24,966 Guard Rail = $ 6,603 Rock = $ 7,571 Engineering = $21,335 TOTAL = $154,035 ($120.83 / sq. ft.)
Total Bridge Costs per ft2 Total Cost = $97.48 / sq. ft. Total Construction Cost = $90.29 / sq. ft. (no Engineering) Adjusted Construction Cost = $83.05 / sq. ft. (no Engineering or Rock) Case Study Bridges: Side-by-Side Comparison Steel Concrete Total Bridge Costs per ft2 Total Cost = $120.83 / sq. ft. Total Construction Cost = $104.08 / sq. ft. (no Engineering) Adjusted Construction Cost = $98.14 / sq. ft. (no Engineering or Rock)
Superstucture Costs Material Girders = $21,463 Deck Panels = $ 7,999 Reinf Steel = $ 3,135 Concrete = $ 4,180 Labor = $ 5,522 Equipment* = $ 500 SUPER TOTAL = $42,799 SUPER TOTAL = $37.54 / sq. ft. Case Study Bridges: Superstructure Only Comparison (Remove Site Prep, Abutment, Grading & Finishing, Guardrail, Engineering, Rock, Etc) Steel Concrete Superstructure Costs Material Slab Girders = $50,765 Deck Panels = $ 0 Reinf Steel = $ 724 Concrete = $ 965 Labor = $ 4,884 Equipment* = $ 4,000 SUPER TOTAL = $61,338 SUPER TOTAL = $50.61 / sq. ft. • *Added cost to use galvanized steel = $5,453.80 or $0.22 / lb. (includes est. 10% fabrication fee) • ** Cost to use weathering steel is approximately $0.04 / lb. (already included in cost in example) *County Crane (30 Ton) used for Steel, Larger Rented Crane (100 Ton) Required for Concrete (Equivalent County Crane Cost is $1520, would result in Steel Cost of $38.88 / sq. ft. )
Case Study Bridges: Audrain County, MO • 25.8% superstructure cost savings • Same bridge conditions: • Structural Depth = 2 ft. (No Difference in Approaches) • Roadway Width = 24 ft. • Same Abutments for Both Can be Used (Steel Could Use Lighter) • Same Guard Rail System • Same Work Crew Steel: Superstructure $37.54 per sq. ft. Concrete: Superstructure Cost $50.61 per sq. ft.
Lighter Cranes Required (Owner Cranes Can Save Costs) Steel Bridge - Advantages
Lighter Abutments Possible for Steel Bridges Steel Bridge - Advantages
Cast-in-Place Deck on Prestressed Concrete Deck Panels Steel Bridge - Economy
Simple and Practical Details Steel Bridge - Economy
Elastomeric Bearings & Integral Abutments Steel Bridge - Economy
Weathering Steel Steel Bridge - Economy