§ 11.3.1. Definitions

A.

Conditional/Incomplete Design

In a "conditional" design, the designer defers essential elements of the design to someone else. An example of conditional design is one in which, by a note on the drawings, the designer makes the contractor responsible for determining whether the subsurface materials will support the applied wall footing loads. An "incomplete" design does not address all of the requirements in this section. An example of incomplete design is one in which the designer checks only internal wall stability, with the implication being that someone else will check external stability.

B.

Construction Waiver

A construction waiver grants the owner of abutting private property permission to construct, in the right-of-way, a minor structure that is non-standard or is of benefit only to that property. The waiver attaches to the property, being recorded with the county record of deeds. Construction waivers exempt the city from maintaining the structure and from financial liability for property damage or personal injury associated with the structure.

C.

Director

The Director of the Public Works Department or the designee.

D.

Excavation/Backfill Zone

The excavation/backfill zone of a utility is the wedge-shaped area above the utility formed by two inclined planar surfaces, one on each side of the utility, sloping upward at a 45 degree angle (.785 rad) (1 to 1 slope) from the outermost edge of the utility to the ground surface.

E.

Fascia Wall

A fascia wall is constructed over the face of a stable slope to enhance its appearance or to protect the slope from degradation due to weathering. The slope may be stable naturally or may be made stable by nailing or other forms of reinforcement. Fascia walls do not contribute to the overall stability of the slope.

F.

License Agreement

A license agreement grants a second party, such as an individual private property owner, homeowners' association or corporation, permission to use public right of way for a permanent structure that requires maintenance or that poses unusual risk to the city. The license agreement exempts the city from maintaining the structure and from financial liability for property damage or personal injury associated with the structure.

G.

Mechanically Stabilized Earth Retaining Wall

A mechanically stabilized earth retaining wall is composed of facing units and metal strips or geosynthetic (geogrid) reinforcement connecting to the facing units and extending behind the wall into special backfill. The stability of these walls depends on the interaction of the facing units, strips or geogrid, and backfill, acting as a system.

H.

Non-Standard Retaining Wall

A non-standard retaining wall is any wall not meeting the definition of a standard wall.

I.

Product-Specific Information

Product-specific information describes the behavior, performance characteristics or qualities of a material or interacting materials or components and is based on results of standardized tests.

J.

Retaining Wall

A retaining wall is a structure used to support a soil or rock embankment or slope in a vertical or near-vertical configuration in which it would otherwise be unstable because of gravitational forces or applied loads.

K.

Tie-backs, Soil or Rock Nail

Tie-back retaining walls generally refer to walls that consist of post-tensioned anchors, that have been placed in pre-drilled holes, and then grouted in place.

Nailing is the reinforcement of slopes by installing anchors in horizontal or near-horizontal, pre-drilled holes in the soil or rock, usually followed by shotcreting of the slope face. The anchors are not tensioned although they may be proof-tested to confirm the efficiency of the anchor/grout/soil or rock interaction. A fascia wall usually covers the shotcrete surface.

L.

Standard Retaining Wall

A standard retaining wall is a free-standing, cantilever or counterfort wall consisting of cast-in-place, reinforced concrete designed according to AASHTO Standard Specifications for Highway Bridges , latest edition.

M.

Tiered Walls

Retaining walls constructed one behind the other, each wall creating a bench or step, resulting in a terraced slope.

N.

Utility Assignments

The pre-assigned horizontal and vertical positions of the utilities in the street right of way or easement.

O.

Wall Height

The vertical distance from the bottom of the footing, or lowest structural component, to the top of the wall measured along the exposed face of the wall.

P.

Wall Systems

Retaining walls whose performance relies on multiple components acting together as an integral unit. Examples are mechanically stabilized earth retaining walls and walls of any type with underdrains, filter media and porous backfill.