Cold Regions Impacts on Coastal Structures

Steven F. Daly Ph.D., P.E., D.WRE

ERDC Cold Regions Research and Engineering Laboratory

Hanover, NH 03755

Community of Practice in East Coast Navigation and Coastal Structures:

"Inspection, Analysis, Assessment, Repair"December 5-7, 2006

Philadelphia, PA

Cold Regions Impacts on Coastal Structures

• Overview of Coastal Ice Impacts

• Ice Impacts on Coastal Structures– Ice Ride-up and Pile-up

• Laboratory Tests

– Freeze-Thaw Impacts on Armor Stone– Installation Integrity

• National Levee Data Base

• Summary

Coastal Ice Impacts

• Sediment transport• Ice gouging (Lake Erie, Arctic Ocean)• Ride-up and Pile-up of ice• Formation of ice jams at river mouths

• Coastal structures• Blockage of water intakes• Harbors and marinas• Navigation

Ice Impacts on Coastal Structures• Ice Ride-up and Pile-up Dramatic impacts, little

guidance• Freeze-Thaw Impacts on Armor Stone• Installation integrity• Pile Uplift• Changing Water Levels

– Rising water levels: “plucking” – Falling water levels

• Ice rests on riprap• Ice Forces Relatively well understood; guidance

for narrow structures – Narrow and wide structures; vertical and sloped– Crushing, buckling, bending, ice fracture

Ice Ride-up and Pile-up

• An ice shove or ice push occurs when moving coastal ice comes into contact with the shoreline.

• Wind, water drag, thermal expansion drive the ice into shore

Southern Shore of Lake Superior

Alaska: Nome & Barrow

Moved Stone

Green Bay, WI

Long Island, NY

Lake Bomoseen, VT(thermal Expansion)

Ice Ride-up and Pile-up

Ice Models by M. Hopkins

Laboratory TestsGuidance on Design

of Rip Rap Structures

(Sodhi et al, 1996, 1999)

•“Little or no damage during ride up events”•“Most damage to the riprap occurred during pileup events, when the ice could force itself between the piled ice and the riprap”•“Accepting some probability (15%) of riprap failure (exposure of filter cloth) we found the median stone size needs to be 2-3 times the ice thickness”

Installation Integrity

• Freeze-thaw (FT) impacts can be an important factor in seasonal deterioration of the cohesion in soils of vegetated earthen levees and embankments where seasonal frost forms

• The strength of vegetated frost-susceptible soils is often at an annual low after soil thaws in the spring when– Newly thawed soils are especially prone to mass failure and

highly susceptible to water erosion– High annual water stages occur due to snowmelt

• Formation and expansion of ice beneath riprap

• Freezing of unprotected slopes • Heaving; slumping when melting; piping

Pile Uplift

• Cyclic freeze-jacking process can slowly extract piles from their foundations over the course of a winter, destroying the piles and the structures attached to them.

Pile jacking, Great Lakes

• Cyclic freeze-thaw cracking• Depends on rock type and susceptibility

• Placement of cold stone in warm water

• Late-winter quarrying• “physical basis ..unclear”

Freeze-Thaw Impacts on Armor Stone

•TR GL 81-8•Canadian Electrical Assoc.•Wuebben 1995

Stone damage at Stone damage at Cleveland DikeCleveland Dike

19971997

National Levee DatabaseInitiate the development of an *SDSFIE-compliant

geospatial National Levee Database including all necessary attributes of levees/floodwalls relevant to design, construction, operations, maintenance, repair, inspections, and potential for failure. ….The database structure shall be the same at every District to assure commonality of levee data with other agencies (Federal, state and local)….. The databases shall be maintained at District level and be accessible as a regional/national database by Division and HQUSACE users. In this Pilot effort, the reporting requirements of the Flood Control and Coastal Emergencies (FCCE) program, as described in EP-500-1-1, will be the used as the test metric for success.

*Spatial Data Standards for Facilities Infrastructure and Environment

SDSFIE Levee Data Model Features

piezometer_pointpiezometer_point

borehole_point borehole_point

levee_inspection_pointlevee_inspection_point

sand_boil_pointsand_boil_point

levee_flood_fight_sitelevee_flood_fight_site

levee_break_sitelevee_break_site

levee_inspection_linelevee_inspection_line

cross_section_linecross_section_line

encroachment_siteencroachment_site

floodwall_linefloodwall_line

levee_centerlinelevee_centerline

protected_areaprotected_area

levee_pump_station_sitelevee_pump_station_site

levee_relief_well_sitelevee_relief_well_site

closure_structure_pointclosure_structure_point

levee_crossing_sitelevee_crossing_site

levee_station_pointlevee_station_point

gravity_drain_sitegravity_drain_site

Cold Regions Impacts on Coastal Structures- Summary

• Ice can impact coastal structures in a variety of ways• The state-of-the-art in understanding and estimating ice

impacts has advanced considerably in the last 25+ years• However, predicting the impact on 3-D coastal structures

of large ice sheets driven by wind and water drag over existing shoreline bathymetry still remains difficult.

• There is still a role for model tests: CRREL is currently working with AK District to conduct model tests of ice ride-up and pile-up on proposed shore protection dikes at Barrow, AK

• Numerical models are increasingly accurate in their ability to simulate ice and estimate forces

References• Sodhi, D, et al (1996) Ice action on riprap: small-scale tests. CRREL Report

No: CR 96-12 U.S. Army Cold Regions Research and Engineering Laboratory Report, 64p.

• Sodhi, D and C. Donnelly (1999) Ice effects on riprap: model tests. Proceedings 10th International Conference on Cold Regions Engineering, Lincoln, NH, Aug. 16-19, 1999. Putting research into practice. Edited by J.E. Zufelt, p.824-837. Publisher: American Society of Civil Engineers (ASCE). Reston, VA, USA

• Lutton, R.J., et al (1981) Evaluation of quality and performance of of stone as riprap or armor. US Army Corps of Engineers Waterways Experiment Station, Vicksburg, MS. Technical Report GL-81-8

• Matheson, D.S. (1988) Performance of riprap in northern climates. Contr. Report CEA No 625 G 571. Canadian Electrical Associates.

• Wuebben, J (1995) Ice Effects on Riprap. River, Coastal and Shoreline Protection: Erosion Control using Riprap and Armor Stone. Edited by C.R. Throne, et al. John Wiley and Sons.

• Hopkins, M. (1997) Onshore Ice Pile-up: comparison between experiments and simulations. CRST 26(1997) 205-214