Paul Clopper, P.E. Ayres Associates Inc Fort Collins,...
26
Paul Clopper, P.E. Ayres Associates Inc Fort Collins, Colorado
Transcript of Paul Clopper, P.E. Ayres Associates Inc Fort Collins,...
Paul Clopper, P.E.
Ayres Associates Inc
Fort Collins, Colorado
Volume 1: Policy, Functional Applications, Selection, Inspection, Maintenance, and Case Studies
Volume 2: Design Guidelines (19 detailed guidelines)
HEC-23 is used by state DOTs and other agencies as the authoritative reference for protecting transportation infrastructure from erosion damage
Protection against stream instability… Fossil Creek, Ft. Collins CO
Fossil Creek, Ft. Collins CO
Protection against bridge scour
Closed: Dec. 3, 2013 Re-opened: Dec. 15, 2013 Courtesy FHWA and NCDOT
Bonner Bridge, North Carolina
Bonner Bridge, North Carolina
Courtesy FHWA and NCDOT
Stream Instability Countermeasures
Armoring
Stream Instability Countermeasures
Flow redirection / River training
Stream Instability Countermeasures
Biotechnical Treatments
Stream Instability Countermeasures
Biotechnical Treatments
Stream Instability Countermeasures
Biotechnical Treatments Distance across cross section, ft
Ele
vatio
n, ft
Stream Instability Countermeasures
Detroit riprap
Stream Instability Countermeasures
Check dams / Drop structures
Presenter
Presentation Notes
Upper: From South Dakota DOT, early 1990’s ? Lower: Big Dry Creek, Centennial Colorado, 2014. Not an Ayres structure, but within the Ayres Master Drainage Plan project.
Stream Instability Countermeasures
Check dams / Drop structures
Presenter
Presentation Notes
St. John’s weir, Guadalupe River, Santa Clara, California. 10 feet of drop over 400 feet; replaced failed concrete check dam. Photo 2005 +/- ? Ayres project (Dusty Robinson).
How do I select a countermeasure?
Use the Countermeasure Selection Matrix: Group 1: Hydraulic Countermeasures
A. River Training Structures B. Armoring Systems
Group 2: Structural Countermeasures Group 3: Biotechnical Countermeasures Group 4: Monitoring
Questions the Matrix will Answer:
• What type of problem does the countermeasure solve?
• What type of river environment is the countermeasure suitable for… or where will it NOT perform well?
• What level of resources will be required for maintenance?
• What states have experience with this countermeasure?
• Where do I obtain design guidance?
HEC-23 Design Guidelines
DG 1 – Bendway Weirs/Stream Barbs DG 2 – Spurs DG 3 – Check Dams/Drop Structures DG 4 – Riprap Revetment DG 5 – Riprap Design for Embankment Overtopping DG 6 - Wire Enclosed Riprap Mattress DG 7 – Soil Cement DG 8 – Articulating Concrete Block Systems DG 9 – Grout-Filled Mattresses DG 10 – Gabion Mattresses
HEC-23 Design Guidelines
DG 11 – Rock Riprap at Bridge Piers DG 12 – Partially Grouted Riprap at Bridge Piers DG 13 – Grout/Cement Filled Bags DG 14 – Rock Riprap at Bridge Abutments DG 15 – Guide Banks DG 16 - Filter Design DG 17 – Riprap Design for Wave Attack DG 18 – Riprap Protection for Bottomless Culverts DG 19 – Concrete Armor Units
HEC-23 Filter Design
Seepage flow
Normal water level Groundwater
table
a) Normal (baseflow) conditions
Seepage flow
Flood water level
b) During flood peak
HEC-23 Filter Design
c) After flood recession
Seepage flow
Normal water level
Area of high seepage gradients and uplift
pressure
HEC-23 Filter Design
What’s NOT covered in HEC-23? Rolled Erosion Control Products (RECPs)
• Erosion Control Blankets • Turf Reinforcement Mats Hydraulically- or Pneumatically-Applied Products
• Mulches • Tackifiers • Bonded Fiber Matrices These products are addressed in HEC-15, “Design of Roadside Channels with Flexible Liners” (FHWA, 2005)
How do I get a copy?
Volume 1: https://www.fhwa.dot.gov/engineering/hydraulics/pubs/09111/09111.pdf Volume 2: https://www.fhwa.dot.gov/engineering/hydraulics/pubs/09111/09112.pdf
How do I get a copy?
Or Google: “HEC-23 2009”
Paul Clopper, P.E.
Ayres Associates Inc
Fort Collins, Colorado
