Driveway ramps for parking structures shall conform to the standards
prescribed in this division.
(Ordinance 1929 adopted 9/23/13)
For the purpose of construing and enforcing this division, certain
abbreviations, words, terms, phrases and their derivatives shall have
the same meaning and/or be consistent with their use and meaning in
division 2 of this article. All other words shall have their usual
meaning.
(Ordinance 1929 adopted 9/23/13)
(a) The
width of the ramp, radii for all curves, length of the landing area
and the percent of slope, the length of the ramp at the specified
slope, and design elevations on both sides of the ramp at all break
points (plus along the center of travel lanes in curves) must be shown
on the plan and profile presented to the building inspection department
with an application for a building permit for a parking structure,
either above-ground or underground, that requires a ramp up or down
from the grade of the base of the structure.
(b) All
horizontal and vertical curves for ramps shall have adequate sight
stopping distance and entrance and exit points to ensure public safety.
(c) Horizontal
alignment that approximates the geometric requirements of circular
curves and tangents shall be used. All vertical curves shall be parabolic,
have equal tangents, and a change in curvature that is constant.
(d) The
principal control in the design of crest vertical curves is to ensure
that stopping sight distance (SSD) is available throughout the vertical
curve.
(e) The
principal control in the design of sag vertical curves is to ensure
that stopping sight distance (SSD) is available for headlight illumination
throughout the sag vertical curve.
(Ordinance 1929 adopted 9/23/13)
(a) Design
speed (DS): 5 mph.
(b) Design
vehicle (high-profile vehicle): 80.0 inches.
(c) Design
vehicle (minimal under-body clearance): 5.6 inches.
(d) Stopping
sight distance (SSD) object height: 2.0 feet.
(Ordinance 1929 adopted 9/23/13)
The driveway within the right-of-way shall have a minimum elevation
change of +0.5 feet. Sidewalks shall meet slope criteria of the Americans
with Disabilities Act (ADA).
(Ordinance 1929 adopted 9/23/13)
All ramps shall have a landing area with a maximum slope of
one (1) vertical unit in twelve and one-half (12.5) horizontal units,
or eight percent (8%). The landing area shall have a minimum length
of fifteen feet (15') measured from the intersection of the ramp and
the property side of the sidewalk of the site. No vertical curve shall
be allowed within the landing.
(Ordinance 1929 adopted 9/23/13)
(a) Parking
garages on commercial properties that provide twenty-five (25) or
fewer parking spaces shall have, at a minimum, one (1) access ramp
to facilitate two-way traffic.
(b) Parking
garages that provide twenty-six (26) or more parking spaces shall
have, at a minimum, one (1) access ramp to facilitate two-way traffic.
Sites with parking structures that provide twenty-six (26) or more
parking spaces may have two (2) or more one-way access ramps in lieu
of one (1) two-way access ramp.
(Ordinance 1929 adopted 9/23/13)
(a) The
maximum slope for the ramp, other than the landing area, shall be
one (1) vertical unit in eight (8) horizontal units, or twelve and
one-half percent (12.5%).
(b) At
the top and bottom of the ramps, vertical curves shall be used to
provide smooth transitions at all changes in slope.
(c) The
driveway surface entering into a subterranean parking structure shall
not be more than thirty (30) inches below the natural front yard grade
when the driveway is located between the front property line and the
front building line.
(Ordinance 1929 adopted 9/23/13)
(a) The
minimum width for a one-way ramp is twelve feet (12'), with an additional
one foot (1') on each side for clearance to the structure and/or retaining
wall, or a total minimum width of fourteen feet (14').
(b) Ramp
widths shall be measured from face to face of any side curbs, walls
or structures, and shall be the width of the actual driving surface.
On sites providing twenty-six or more parking spaces, ramps less than
twenty feet (20') in width shall be posted for one-way traffic. On
sites where a single ramp less than twenty feet (20') wide is allowed,
signage shall be posted warning drives of potential oncoming ramp
traffic.
(c) Convex
mirrors, placed on private property, are required where opposing motorists
cannot readily view each other and/or where ramps are too narrow to
permit vehicles to bypass each other.
(Ordinance 1929 adopted 9/23/13)
All ramps shall have at least ten feet (10') sight triangles
through which drivers can see pedestrians in the right-of-way. The
ten feet (10') sight triangles shall be measured from the intersection
of the ramp and the property side of the sidewalk of the site.
(Ordinance 1929 adopted 9/23/13)