BDCS Flashcards
Ahwahnee Principles
collective vision of how urban and suburban planning should follow certain fundamental principals regarding community size, integration, transportation, open space, pedestrian paths, native vegetation, water and energy use
Winds: Basic speed Unnoticeable Pleasant Pleasant & noticeable Drafty Uncomfortable
70 - 80 miles/hour <50 feet/minute 50 - 100 ft / min 100 - 200 ft / min 200 - 300 ft / min \+ 300 ft / min
Noise: sleeping / studying Conversation, comfort safety threshold rock band!
30 decibels
50 - 60 decibels
85 decibels
90-100 decibels
simple beam
rests on a support at each end and ends are free to rotate
Cantilever beam
supported at one end and restrained from rotation at that end
overhanging beam
rests on 2+ supports and has one or both ends cantilevered beyond the support
Gage line
standard dimension from corner edge of an angle to centerline of bold holes
ductility
can deform and return to original shape / bends before it breaks
one-way concrete joist system
pan joists
prefab metal pan forms are used to create frame to support light/medium loads
spans of 20’-30’, depth 1’-2’
two-way concrete joist system
typically used in rectangular bays where distance between columns is equal (or close to) in both directions
flat plate system
two-way slab with no supporting beams, only columns
reinforced slab spans in both directions directly into columns at 25’ with 6”-12” thickness
used for light loads, short spans, when floor-to-floor height must be minimized
drop panel system
like flat plate system but the slab thickness is increased around the columns for greater shear failure resistance
used with greater live loads or larger spans
typical arch spans
wood
concrete
steel
wood: 50’ - 240’
concrete: 20’ - 320’
steel: 50’ - 500’
trusses:
typical depth-to-span ratios
typical spans & spacing
depth-to-span ratios: 1:10 to 1:20
spans: 40’ - 200’
spacing: 10’ - 40’ o.c.
construction weight / floor
Timber
Steel
Concrete/masonry
Timber: 7-10 lbs/sf
Steel: 15-20 lbs/sf
Concrete/Masonry: 150-200 lbs / sf
Concept Model
methodology for measuring the embodied energy in historic buildings
a planning approach where various building types are given embodied energy values based on the square footage. Gives a rough estimate
Inventory Model
methodology for measuring the embodied energy in historic buildings
Uses an accurate accounting of the material used in construction. Is more accurate than the concept model
Survey Model
methodology for measuring the embodied energy in historic buildings
assumes that most of the embodied energy in a building is contained in the bulk of the architectural materials
halftimbering
braced wall framing exposed on the face of the building where the space between the timbers was filled with brickwork or wattle and daub
NESHAP
National Emission Standards for Hazardous Air Pollutants
EPA regulation that dictates requirements of ACM removal before remodel/demo in order to prevent significant asbestos release into the air
AHERA
Asbestos Hazards Emergency Response Act
EPA regulation that handles asbestos found in k-12 schools, and requires that all facilities be inspected to determine the presence of amount of asbestos
types of fires
Type A: wood, paper, plastic, cloth
Type B: flammable liquids, grease, gas
Type C: Electrical
Type D: Combustable metal
Types of fire extinguishers
Water extinguisher - class A fires
CO2 extinguisher - class B fires
ABC extinguisher - Class A, B, or C fires
K extinguisher - Class B fires (cooking oil)
Biophilia
the connections that humans subconsciously seek with the rest of life
Retrocomissioning
systematic investigation process applied to existing buildings to improve and optimize operating / maintenance
organic feedstock
something organic (wood fiber, paper, cotton, ect) that mold can use as an energy source. mold cannot eat inorganic materials
U-factor
measure of heat transmission
low U-value = slow heat loss (brick wall)
high U-value = rapid heat loss or gain (window)
R-value
measure of thermal resistance in a component
opposite the U-value
thermal inertia
ability of a material to store heat (concrete/masonry walls store heat in an arid climate and release slowly at night)
Area of Refuge
a location designed to hold occupants when evacuation is not safe or possible. Has a steady supply of outside air, passive fire protection, electrical integrity/emergency lighting, two way communication/call box to 24 hr manned, or outside line
Fire Walls
walls that divide a single building into two or more “buildings”, if either side collapses the wall will not for the duration of its rating
Fire Barriers
make up rated assemblies/enclosures (e.g. shafts, exit enclosures, exit passageways, horizontal exits, atrium, mixed use occupancy separation)
shaft enclosures
openings through floors/ceilings connecting adjacent floors. 1 hour rated when connecting less than 4 stories. or 2 hour if passing through a 2 hour floor assembly or if connecting 4 or more stories
Fire Partition
demising walls separating tenants, residential units, corridor walls
Smoke Barrier
used as required to prevent the movement of smoke, have a 1 hour fire resistance rating
Smoke Partition
like a smoke barrier, but does not have to resist fire
corbel
a projection of brick jutting out from a wall to support a structure above it
point
filling joints to the face with mortar and tooling them to the desired profile
needle beam
a temporary member thrust under a building or foundation used in underpinning
retempering mortar is safe within what time frame?
if mortar is mixed less than 90 minutes prior to its stiffening it has only dried and a mason can safely retemper with water to make it workable again (note the case with concrete)
when to discard mortar?
mortar older than 2 1/2 hours must be discarded because it has begun to hydrate and can’t be retempered without reducing its final strength
Mortar
made of portland cement, hydrated lime, inert aggregate (sand), and water
common brick size
8 x 3 5/8 x 2 1/4
when are mortar joints in brickwork tooled?
1 - 2 hours after laying as the mortar begins to harden
igneous rock
rock that was deposited in a molten state
granite, basalt
sedimentary rock
deposited by the action of water and wind
limestone, sandstone, brownstone
metamorphic rock
formerly either igneous or sedimentary rock transformed by heat or pressure
marble, soapstone, slate
cramp anchors
used under coping stones at vertical joints to tie 2 stones together
pin anchor
anchor placed into a drilled hole and a pin is hammered in
threaded dowel
used at vertical / horizontal joints between panels to align and maintain distance between panel and backup structure
dovetail anchor
splayed tenon that fits into the recess of a corresponding mortise
weep hole locations
24” apart in brick
32” apart in CMU
internal (concealed) flashing
turned up 6” - 9” at the interior face of the wall
should penetrate at least 2” into the interior wythe
flashing materials
sheet metal, plastic, elastomeric compounds, composite material
sheet metal is the most durable and most expensive
copper and stainless steel is best
galvanized steel eventually rusts and disintegrates
aluminum and lead are unsuitable because they react chemically with mortar
plastics are least expensive - some good, some bad
surface divider joints
must be provided to avoid excessive buildup of forces that could crack or spall the masonry
abutment / construction / isolation joints
placed at junctions between masonry and other materials, or between old and new masonry to accommodate differences in movement
Parge
below grade, masonry should be parged or plastered on the outside with two coats of Type M mortar to seal cracks and pores
bulb tee
a steel reinforcing member used when constructing pre-stressed, poured gypsum deck. when the gypsum is poured, it surrounds the bulb-tee
primary type of steel used for structural purposes
ASTM A36
less expensive steels used with scraps / recycled content
ASTM A572, ASTM A992
structural shapes
W: wide flange
W 12x 36 = nomical depth in inches x weight per foot of length in lbs
S: American standard
L: angle
C: channel
WT: structural tee
intumescent paint
thin coatings - expand when exposed to fire to form a thick, stable char that insulates from heat
castellated beam
beam produced by cutting the web of wide flange along a zigzag, then reassembling the beam by welding its two half point to point, increasing its depth without inscreasing the length
plate girders
custom designed and fabricated for long span beams
steel plates and angles are assembled by bolting or welding in such a way as to put the steel where it is needed for the required loads
stud framing spacing
wood = 16" o.c. metal = 24" o.c.
chambered
steel beams and girders are curved slightly upward so they will deflect in a straight line once loads are applied on site
lamella
a thin finished top layer of an engineered wooden floor
plainsawed
most lumber intended for use in building framing
maximum yield of lumber from a log
pieces distort differently during seasoning
quartersawn
wood that will be seen in finish applications
produce lumber that have annual rings running nearly perpendicular to the face of the piece
boards tend to remain flat
freewater
water held in the cavities of the cells
reduces water content to 26%-32% moisture
bound water
water held in within the cellulose of the cell walls, wood starts to shrink at this point and the strength and stiffness of the wood begins to increase
longitudinal shrinkage
shrinkage along length of the long is negligible
radial shrinkage
shrinkage in the radial direction is very large by comparison
tangental shrinkage
shrinkage around the circumference of the log is about half again greater than the railed shrinkage
natural wood defects
knots and knotholes
insect damage
decay
manufacturing wood defects
splits and checks
wane
crooks, cups, bows and twists
stronger, more expensive wood species
used for highly stressed major members
Douglas Fir
weaker cheaper wood species used for structure
Eastern Hemlock
board feet =
(cross section area / 12) x length
ex. 10 foot long 2 x 4
(2 x 4 / 12) x 10 = 6/67 board feet
LVL
laminated veneer lumber
uses the veneers in sheets and looks like thick plywood with no crossbands
stronger, straighter, and more uniform than conventional lumber
waferboard
large wafer like flakes of wood compressed and bonded into panels - largely replaced by OSB
particleboard
smaller wood particles compressed and bonded into panels and used as a base material for cabinets or underlayment for resilient flooring
fiberboard
very fine grained board amide of wood fibers and synthetic resin binders used in cabinets, furniture, moldings
MDF (medium density fiberboard)
exposure durability classification
Exterior
suitable for use as siding or other permanently exposed applications
exposure durability classification
Exposure 1
have fully waterproof glue but don’t have veneers of as high a quality as exterior. can be used for structural sheathing and subflooring
95% of structural panel products are exposure 1
exposure durability classification
Exposure 2
suitable for panels that will be fully protected from weather and will be subjected to a minimum of wetting during construction
nails for Western Red Cedar
Hot dipped galvanized, aluminum, and stainless steel (best option)
all others can rust and disintegrate and react with the oils present in the cedar
carriage bolts
round headed bolt used for timber, threaded along the shank and inserted into holes already drilled
lag bolts
heavy woodscrew with a square or hexagonal head that is driven in with a wrench
split ring connector
high capacity connectors used in heavily loaded joints of timber frames and trusses
spreads the load across a much greater area of wood
toothed plates
used in factory produced lightweight roof and floor trusses, inserted with hydraulic presses or mechanical rollers, and act as metal splice plates each with a very large number of built-in nails
framed panel
a section of framing about 4’ wide, sheathed with a sheet of plywood, OSB, or waferboard
stressed skin panel
faces are bonded with adhesive to thin wood spacers to form a structural unit
sandwich panel
functions the same as a stressed skin panel but are bonded to a core of foam insulation instead of wood spacers
headers / Rim joists / Band joists
crosspieces at the ends of joists
sole plate
cross piece at the bottom of a wall in wood light frame construction
top plate
cross piece at the top of a wall in wood light frame construction
ridge board
peak where rafters are headed off in wood light frame construction
tarpaper
acts as an air barrier and backup waterproofing layer
allows water vapor to pass freely so that it doesn’t accumulate on the wall
housewraps (Tyvek)
airtight, vapor permeable papers made of synthetic fibers are stapled to sheathing in as large of sheets as possible to minimize seams.
bush hammering
process of creating a rough, pockmarked texture on concrete or stone that resembles naturally weathered rock
cement established by ASTM Type I Type IA Type II Type IIA Type III Type IIIA Type IV Type V
Type 1 - normal (used for most construction)
Type 1A - normal, air entraining
Type II - moderate resistance to sulfate attack
Type IIA - moderate resistance, air entraining
Type III - high early strength
Type IIIA - high early strength, air entraining
Type IV - low heat of hydration (massive structures, dams)
Type V - high resistance to sulfate attack (used when in contact with water with high concentration of sulfates)
air entrained cements
contain ingredients that cause microscopic air bubbles to form in the concrete during mixing which give improved workability during placement, and greatly increases the resistance of the cured concrete to damage caused by repeated cycles of freezing and thawing
used for paving and exposed concrete in cold climates
water reducing admixtures
allow a reduction in the amount of mixing water while retaining the same workability, results in a higher strength concrete
high range water reducing admixtures (superplasticizers)
organic compounds that transform a stiff concrete mix into one that flows freely into forms, used to help place concrete in challenging circumstances, or to reduce the water content in a mix in order to increase strength
accelerating admixtures
cause concrete to cure more rapidly
fly ash
a fine powder that’s a waste product from coal-fired power plants, which increases concrete strength, decreases permeability, increases sulfate resistance, reduces temperature rise during curing, reduces mixing water, improves workability
silica fume (microsilica)
a powder 100x finer than portland cement, a byproduct of electronic semiconductor chip manufacturing that when added produces extremely high strength and low permeability
blast furnace slag
byproduct of iron manufacture that improves workability, increases strength, reduces permeability, reduce temperature rise during curing, and improve sulfate resistance
corrosion inhibitors
used to reduce rusting of rebar in structures that are exposed to road deicing salts or other corrosion causing chemicals
absolute water cement ratio
0.60 - the weight of water shouldn’t be more than 60% of the weight of the portlant cement
concrete must be kept moist until
its required drying strength is achieved
column tied
bands are wired at required spacing and used for square, circular or rectangular columns. generally more affordable than column spirals
column spirals
shipped to the construction site as tight coils that are expanded accordion style to the required spacing and wired to the vertical bars
shotcrete
concrete sprayed into place pneumatically and used primarily for repairing damaged concrete on the faces of beams / columns
precast concrete floor and roof slabs
solid flat spans
hollow core slabs
double tees and single tees
manufactured with a rough top and 2” topping slab is poured to unify finish and help elements act together
