Environmental and Contextual Conditions Flashcards
Catchment Area
In human geography, a catchment area is the area from which a city, service or institution attracts a population that uses its services. For example, a school catchment area is the geographic area from which students are eligible to attend a local school.
Proctor Compaction Test
a laboratory method of experimentally determining the optimal moisture content at which a given soil type will become most dense and achieve its maximum dry density.
Baseline Survey
In the United States Public Land Survey System, a baseline is the principal east-west line (i.e., a parallel) upon which all rectangular surveys in a defined area are based. The baseline meets its corresponding principal meridian at the point of origin, or initial point, for the land survey
Equinox
Winter: December 21
Summer: June 21
Vernal: March 21
Autumnal: September 21
Altitude/Azimuth
angle above the horizon/angle north or south from an east-west line
Cool Climates
Use compact forms with the smallest surface area possible relative to the volume
Use large, south-facing windows with small windows on the east and west and with minimal or no windows on the north
Use interior materials with a high thermal mass
Include summer shading for glazed areas
Use dark or medium-dark colors for the building exterior
Temperate Climates
Plan rectangular buildings with the long direction oriented generally along the east-west axis and facing slightly to the east. for the cooling effects of wind in the summer; block the win.d in the winter.
Use medium colors for the building exterior
Provide shade in the summer, and allow the sun to fall on glazing and the building in the winter.
Use south-facing openings to capture winter sunlight.
Plan
Hot-Humid Climates
Provide shade for all openings.
Maximize natural ventilation with large openings, high ceilings, and cross ventilation.
Construct buildings using light materials; minimize thermal mass.
Use light colors for the building exterior.
Hot-Arid Climates
Use compact forms with the smallest surface area possible relative to volume.
Minimize opening sizes.
Provide shade for openings.
Maximize thermal mass.
Use light colors for the building exterior.
Aboveground Drainage
involves sheet flow, gutters built into roadways and parking area, ground swales as par t of the landscaping, and channels.
Underground drainage
utilizes perforated drains and enclosed storm sewers that carry the runoff from the site to a municipal storm sewer system or to a natural drainage outlet such as a river.
Sheet flow
water that drains across a sloping surface, whether paved, grassy, or landscaped.
Existing Utilities
Sanitary sewers and storm sewers usually take precedence in planning because they depend on gravity flow. The invert, or lowest, elevations of the existing public sewer line should be established, since the effluent must flow from the lowest point where the sewer line leaves the building to the main sewer.
Building sewer
the portion of horizontal piping of the sanitary sewer system between the building and the sewer main. Minimum slope of the building sewer is 0.5% to 2.0% depending on the size of the pipe. (1% is 1/8” / ft.)
Road slope
15% maximum for short distances, 10% or less preferred. If sloped 10% or more, transition slopes of one-half the maximum slope should be provided. Roads should also have 1/4”/ft slope for drainage from the center of the roadway, called the crown, to the sides, called the gutter.
Sidewalk slope
1/4”/ft for drainage across walk, maximum
4% (1/2”/ft) mas at buildings
6% max preferred elsewhere
8% absolute max
Exterior Stairs
Minimum 3 risers / Maximum 10 risers between landings
rise 4” min. / 6” max.
run 14” for 6” rise
slope 1/4”/ft. for drainage
provide handrail over four risers or where icy conditions exist
Design Guidelines for Service Drives
12' to 14' one way drive 45' outside radius for straight body truck 20' inside radius 35' to 50' reversing drive 10' to 12' loading dock
Parking Spaces
9’ x 19’ standard
7.5’ x 15’ compact
Parking Lot Layout
1.5% - 5% slope for drainage
(use 2% or 3%)
90 Degree Parking - Most Efficient
62’ minimum double loaded (19’ parking + 24’ aisle)
45 Degree Parking
52.6’ minimum double loaded (19.8’ parking + 13’ aisle)
Accessible Parking
Located close tot he building entrance
Identified with international symbol for accessibility
Van-accessible access aisle 96 inches (8’)
Car-accessible access aisle 60 inches (5’)
2% maximum slope
Landscaping
7’ median minimum for trees
4’ median minimum for grass
Maekawa equation
used to evaluate the reduction in noise decibels (NRdb) from a point source
Basic principles for designing outdoor sound barriers
Generally, solid barriers block high-frequency sounds better than low-frequency sounds.
The barrier is best placed as close as possible to either the source of the noise or the receiver.
If the barrier is close to the noise source, it should be at least four times as high as the distance from the source to the barrier.
The greater the effective height (the distance from the acoustic line of sight to the top of the barrier), the greater the attenuation.
For blocking noise from a point source, a short barrier should be at least four times as long as the distance from the barrier to the source or the distance from the barrier to the receiver, whichever is shorter.
A barrier should have a density of at least 5 lbm/sq ft and be solid. However, greater densities than this do not increase sound attenuation significantly.
