Site Analysis Flashcards
Solar orientation
key considerations:
orientation of building to control solar heat gain/loss. location of outdoor spaces & activities. location of building entires
Solar altitude
angle above horizon
azimuth
angle north/south from east-west line
climatic regions in us
cool - canada, north/middle US, mountains of wyoming/co
TEMPERATE - middle US, NW & NE
Hot humid - SE
Hot Arid - SW
Cold climates general rules of thumb
minimize exposed surface area, compact forms, minimize heat loss. bury in hill/land.
minimize openings on N face, large windows on S face
entries to have air locks
landscape to block winds
mechanical heating & active solar heating - NO PASSIVE
increase thermal mass materials
dark exterior colors
Temperate climate general rules of thumb
minimize northern exposure, max southern exposure
block winter winds
provide night time ventilation for exhaust of hot air
passive & active solar heating
medium colors for exterior
block cold winter wind, accept cool summer wind
block summer sun, accept winter sun
Hot Humid climates rules of thumb
long, narrow. max cross ventilation. large windows, porches, breezeways
shade needed - trees or double roof
minimize thermal mass
provide shade for all openings
light exterior colors
Hot Arid climates rules of thumb
shade from direct sun
max thermal mass
night ventilation
pools of water can reduce local air temp
compact forms, small surface area
minimize openings & provide shade
light exterior colors
Passive solar heating
long, narrow building along e-w axis. integrate with daylighting design. thermal mass as design element. deciduous trees
Passive solar cooling
shading, natural ventilation, evaporative cooling
radiative cooling
thermal mass store heat in day & release at night
ground cooling
use coolness of earth to cool a building. uses ground source heat pumps
active solar
pv panels, mount to roof
Slope
G = d/l x 100%
G - slope of land
d - vertical distance between contours
l - horiztonal distance between points
Soil
pulverized upper layer of earth. categorized according to grain size, organic/inorganic
Gravel
larger than 2mm diameter
good for construction loads, drainage, sewer fields
not good for landscaping
Sand
0.05-2mm diameter. finest grain visible to eye
good for construction loads, drainage, sewer fields
not good for landscaping
Silt
0.002mm - 0.05mm diameter. can’t see, but can feel
stable when dry, unstable when wet. swells/heaves
not good for raods or foundations unless extend below layer or are elastic to avoid damage
Clay
less than 0.002mm diameter
expands when wet and slippery
not good for foundations or landscaping or sewer fields
retains water & drains slowly
Peat & organic materials
good for landscaping
not good for foundations/road bases
usually must remove from site & replace with sand/gravel
what soils have highest bearing capacity ?
bedrock, shale, slate
hard pan
unbroken mixture of clay, sand and gravel
standard penetration test
soil boring that takes a measure of density of granular soils and consistency of clays within sample
- measured in number of blows required to move boring a certain distance
auger borings
used only for sand and clay. uses a standard auger bit
wash borings
a water jet forces materials into a 2-4” D pipe. results in a heavily mixed boring
karst landscape
an area comprised of soluble rocks, limestone, dolomite, or gypsum. the soil dissolves to form caves and peaks and can form sinkholes
drainage
used to increased strength of soil
fill
undesirable existing soil is remvoed from the site and new fill is brought in. new fill must be compactedp
proctor test
determines optimal moisture content at which a given soil type achieves its maximum dry density
sheepsfoot roller
machine used to compact fill
densification of soil
achieved through on-site compaction, vibration, heavy weights, and piles filled with sand
surcharging
pre-loading the ground with fill to compact and settle the underlying soil. then remove fill before constructionm
mixing
add a layer of sand or gravel and mix into existing soil
frost/frost line
foundations and footings should be placed below the frost line, the deepest point in the ground to which ground water will freeze
angle of repose
natural angle a pile of dirt takes when at rest
silt fence
used during construction to catch eroded sediment on site before it enters the storm sewer. fences are placed parallel to contours
gully erosion
removal of soil along drainage lines by surface water runoff
deep, wide, and unstable channels are formed
sheet erosion
uniform overland flow, can be difficult to notice
splash erosion
first stage in erosion process that occurs when raindrops hit bare soil
rill erosion
removal of soil by concentrated water running through small stremlets
