Commonly Used Terms
Seawalls & Bulkheads: Commonly Used Terms and Definitions
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Anchor
The buried portion of the tie-back rod that is typically a reinforced concrete block, which engages the soil to resist the pull on the tie-back rod. Also known as a deadman.
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Batter
The angle from plumb (vertical) deliberately constructed for a bearing pile.
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Berm
The ground or soils which support the base of the panels, may also include rip rap.
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Bulkhead
Bulkhead and Seawall are often referenced together. They are interchangeable terms. A bulkhead is any solid vertical structure, which serves to separate landward real property and/or any improvements thereon from any natural or manmade body of water. Typically constructed in areas experiencing mild to moderate exposure such as protected waters in rivers, canals, bays, etc.
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Bulkhead Repair
A bulkhead repair (or seawall repair) is the process to protect your property from erosion. ARQA Marine Foundation solutions is a low cost seaside repair process leaving your land-side property un-disturbed.
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Concrete Cap
The component on top of the seawall panels used for alignment and/or structural support.
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Deadman
Poured concrete block approximately 10’ to 15’ landward of the seawall, connected to seawall with tie rods, used to anchor the structure.
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Erosion
Soil loss from the landward side of the seawall.
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Exposed Height, Reveal
The height of the exposed bulkhead as measured from the berm to the top of the cap.
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Filter Fabric
A geosynthetic fabric manufactured specifically as a filter to inhibit soil movement through the fabric while allowing water to pass through.
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French Drain
A trench dug parallel to the seawall directly adjacent to the cap, common dimensions being 2’ width by 2’ depth, lined with filter fabric and filled with 1” rock. The system is used to allow water to pass from the soil through the seawall in order to relieve hydrostatic pressure.
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Hydrostatic Pressure
The pressure caused by water.
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Pilings
Concrete or wood poles, typically used as supports for docks and boat lifts.
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Penetration
The portion of the sheet pile that extends vertically downward through the “toe-berm”, penetration should be a minimum of 33% of total sheet pile length.
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Return Wall
The portion of a seawall that is parallel to and abutting the adjacent property line, usually this wall is short and is approximately one foot below grade. The return wall provides anchorage and stability to the seawall and provides soil containment.
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Reveal or Exposed Height
The portion of the sheet pile that extends vertically upward from the “toe-berm” to the concrete cap, reveal should be no more than 66% of total sheet pile length.
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Revetment
A sloping structure that serves to separate real property and/or improvements thereon from any natural or manmade body of water.
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Rip-Rap
Large stone placed at the base of the panels to reduce lower rotation and minimize scouring.
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Scouring
Erosion of the soils at the base of the panels that support the lower portion of the seawall, commonly caused by current or wave action.
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Seawall
Any solid vertical structure, which serves to separate landward real property and/or any improvements thereon from any natural or manmade body of water. Typically constructed in areas experiencing moderate to extreme exposure such as open water.
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Sheet Pile or Panels
Preformed structural element providing vertical stability and separation of soil from an adjacent waterway, typically pre-cast concrete panels in this area.
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Spalling
The cracking and chipping of concrete generally associated with the oxidation of the internal steel reinforcing bar.
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Supplemental Supports
Pilings, rip rap, tie-backs: a system used to arrest movement of a seawall.
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T-Pile Seawall
A seawall consisting of specially formed support piles that support sheet piles horizontally with a concrete cap and a tie-back at each pile.
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Tie-Back System
The structural system installed to laterally support the seawall. This system typically consists of a steel rod with one end embedded into the cap and a buried concrete anchor attached to the other end of the rod. However, it could be another assembly performing the same function such as a screw anchor.
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Tie-Rod
The rod connecting the concrete cap to the anchor, part of the tie-back system.
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Toe-Berm
Soil on the waterward side of the seawall, typically underwater, canal bottom.
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Turbidity Barrier
A floating geotextile barrier that confines turbid water to the immediate construction area in accordance with state law.
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Wale, Waler, Wale Beam
A horizontal structural element laterally supporting sheet piles. A concrete cap typically performs this function but a wale can be positioned vertically anywhere along the height of the sheet piles.
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Weep Holes
A hole through a sheet pile to allow water from behind the sheet pile to drain through the wall without the loss of soil.