Sunday Creek Bridge #364C
October 8, 2008Spokane, WA
Doug Walters, P.E.King County DOT
Sunday Creek Bridge Replacement Utilizing Geosynthetic Reinforced Soil (GRS) Abutments
Sunday Creek Bridge #364C
Project Location
Sunday Creek Bridge #364C
Existing Log Stringer Bridge
Sunday Creek Bridge #364C
Bridge Deck
Sunday Creek Bridge #364C
Typical Bridge Traffic Prior to Load Restrictions
Sunday Creek Bridge #364C
Deficiencies
Structural• Timber cribbing abutments & log stringers damaged• Minor scour• 1997- Placed temporary shoring
– load limit of 3 tons
Environmental• Cited by the WA Department of Fish and Wildlife
– Temporary shoring within stream channel
Sunday Creek Bridge #364C
West abutment temporary shoring
I-Beam on Ecology Blocks
Sunday Creek Bridge #364C
East Abutment Temporary Shoring
Shoring Support
Sunday Creek Bridge #364C
Typical rot on log stringers
Sunday Creek Bridge #364C
Superstructure: Prefabricated Steel Truss
Sunday Creek Bridge #364C
Superstructure Selection
• Hydraulic Opening – Above 100 year flood elevation – Changing road grade
• additional environmental permitting
• Narrow Haul Road
Sunday Creek Bridge #364C
Superstructure: Prefabricated Steel Truss
3ft clear space
Sunday Creek Bridge #364C
Foundation ConsiderationsBorings • Alternating layers of medium dense alluvial gravel, sand,
and silt
Abutment Foundation • Shallow foundation• Base of foundation below stream’s thalwag elevation
Sheet Pile Cutoff Walls • Allow dry construction• Provide additional scour protection
Sunday Creek Bridge #364C
GRS Abutment Selection
Constructability• Avoid long concrete haul• Not weather dependent• Reduced time of construction
Cost Savings• Materials• General labor• Standard equipment
Environmental• No concrete placement
Sunday Creek Bridge #364C
GRS Abutment Design Outline
• King County preliminary GRS abutment – NCHRP Report 556 “Design and construction of GRS
abutments”
• Mike Adams (FHWA) reviewed & refined design – Provided GRS design detail with layout
– continue to provide evaluation, design, and construction support
Sunday Creek Bridge #364C
BRIDGE LAYOUT
22 ft
PLAN
104 ft
25 ft
14 ft
Sunday Creek Bridge #364C
GRS ABUTMENT DETAIL
FINISHED GRADE LINE
Sunday Creek Bridge #364C
CMU Block Schedule
11 ft
23 ft
5 ft
11 ft
9 ft
36 ft
Sunday Creek Bridge #364C
Tasks to be completed
• Finalize Design
• Bid January 2009
• Construction June 2009
Sunday Creek Bridge #364C
THANK YOU!Question?