BDCS Terms Flashcards
Wired glass
Wired glass has great resistance to impact and resist shattering when exposed to high heat. Therefore it is used in fire Doors, exterior walls, vertical shaft, and is leading to fire escapes
Pointing
Pointing is adding fresh mortar to existing mortar that is insufficient
Spandrel glass
Is usually heat strengthened glass
Slump test
The standard test measures the workability of concrete
Bulb tees
They are used in gypsum concrete construction as structural sub purlins. They are fastened to the primary framing and provide support for the form boards that receive the gypsum concrete.
Class A doors
three hour rating are used in openings in fire walls or division walls between buildings or sections of buildings or sections of buildings
Class B doors
1.5 hour rating are used in openings in enclosed vertical shafts such as stairs or elevators
Class D doors
1.5 hour rating but are intended for severe fire exposure in exterior walls and no glass is permitted
Incombustible material
A material that will not burn
Needle beam
Is used in the situation where the support load above an opening cut into an existing masonry wall
Acrylic latex
Solvent free paint and therefore prevents no flammability hazard in either storage or application.
Millwork
Shop fabricated items such as doors and window frames, stairways, paneling etc which are fabricated in a mill and delivered to the job ready for installation
Accelerator
A substance, such as calcium chloride, added to a concrete mix to speed up its setting and strength
Admixture
A prepared substance added to concrete to alter or achieve certain characteristics
Aggregate
The chemically inert element of concrete, usually consisting of sand, crushed rock, and or gravel
Air Entrainment
The incorporation of tiny air bubbles into concrete or mortar to improve its workability and resistance to freezing.
Alloy
A substance generally composed of two or more metals that have been intimately mixed.
Asbestos Cement
A material consisting of a mixture of portland cement and asbestos fiber although resistant to fire, it is considered a health hazard.
Asphaltic Concrete
A mixture of asphaltic cement and aggregates, used as a paving material, which is spread and rolled while hot.
Balloon Framing
A method of framing wood stud walls in which the studs are continuous for the full height of the building, which is usually two stories, with the joists bearing on a ribbon let into the studs
Balustrade
A complete railing system consisting of a top rail, supporting balusters and sometimes a bottom rail
Batter boards
Horizontal boards offset from the building line and set prior to excavation, used to indicate a specific location such as the corner of a building
Bed joint
The horizontal mortar joint in masonry work
Bitumen
A substance derived from petroleum or coal used to resist water penetration, such as asphalt or coal tar pitch
Book matching
A way of placing successive veneers sliced from the slame flitch so that alternate sheets appear as a mirror image
Bullnose
The rounding of an exposed edge, such as a tile or wood trim piece
Cant Strip
A beveled strip used to avoid a sharp bend in roofing material
Cofferdam
A watertight temporary structure placed under water and pumped dry to allow construction work to be performed.
Cold joint
A joint formed when a concrete surface hardens before the next batch of concrete is placed against it
Collar Beam
A horizontal tie beam connecting two opposite rafters at a level above the wall plates
Control joint
A groove in a concrete structure made to predetermine the location cracks
Coping
A protective cap of brick, stone, or concrete used at the top of the wall to prevent water penetration.
Dry Rot
Timber decay due to fungus in which pockets of dry powder develop
Efflorescence
The whitish powder of crystallization caused by water soluble salts which comes to the surface when water evaporates from briick
Escutcheon
A metal plate around a knob and or keyhole of a door
Flitch
A large timber from which veneers are cut
Grillage
A framework of horizontal members used to spread a structural load over a larger area
Gunite
Sprayed applied concrete
Hospital tip
Rounded edge on a hinge designed for cleanliness and to avoid catching garments
Intumescent paint
Paint that swells up when exposed to excessive heat and thus resists flame spread
Jalousie
A window or door blind made of fixed or movable horizontal slats
Jetting
PLacing piles using high pressure water jets
Kalamein Door
A type of fire resistive door that has a solid wood core covered with sheet metal
Keene’s Cement
A quick setting gypsum plaster used in areas exposed to moisture
Laitance
Mortar or grout on the surface of concrete
Ledger
Horizontal member supporting joists also called ribbon, grit, purlin or stringer.
Monel
An alloy of nickel and copper that is resistant to corrosion and used for roofing, kitchen
Neat
Describing cement or plaster that has been mixed with water only, without sand or lime
Needle Beam
A short beam passed through a wall to provide temporary support.
Perlite
A lightweight volcanic rock used as an aggregate in lightweight concrete or plaster
Plaster
A mixture of portland cement or gypsum with sand and water which is applied in layers or coats which harden and dry
Platform framing
A method of framing wood stud walls in which the studs are one story in height and the floor joists bear on the top plates
Raked Joint
A mortar joint that has been cleaned of mortar for about 3/4 inch back from the face
Reglet
A slot in which roofing material is inserted, generally in a vertical wall surface.
Shellac
A solution of refined lac resin and denatured alcohol used as a clear coating
Sleeper
A horizontal member used to support a structure above such as one of the wood strips between a concrete slab and finish wood floor
Slump test
A test for mixed concrete to determine consistency and workability
Slurry
A soupy mixture of water and clay or water and portland cement
Stucco
A mixture of sand, portland cement, lime and water that may be tinted and applied as an exterior plaster finish. Applied in three coats Must be kept moist for a week to harden completely
Terne Plate
Steel coated with lead and tin used for roofing and flashing
Tremie
A pipe or tube used to deposit concrete under water
Urethane
A synthetic resin from which paints and insulation foams are manufacturedd
Vermiculite
A lightweight aggregate used in lightweight concrete or plaster
Vitrification
The fusion of a clay product after firing which makes it impervious
Water-cement ratio
The ratio of water to cement in a concrete mix, which is the main factor which determines concrete strength
Water Stop
A device used at a joint as a sealant usually to prevent the passage of water.
Wythe
Each individual vertical tier of masonry in a cavity wall.
flitch beam
combines wood and steel into one member with load carrying capacity far exceeding that of wood alone.
cement paste
the active ingredient in concrete often referred to as the matrix
soft mud process
uses molds into which moist clay is pressed by hand or machine into rectangular molds
stiff mud process
forces the mixture through a die, extruding a clay ribbon that is cut into bricks by tightly stretched wires.
dry-press process
uses a relatively dry mixture that is pressed into gang molds by plungers under high pressure.
wood
the hard fibrous substance lying beneath the bark of trees
lumber
the wood that has been sawn into construction members
timber
the lumber that is five inches or larger in its least dimension
softwoods
pine, fir, and spruce, come from needle-leaved conifers which are evergreen. can be used for framing, sheathing, bracing.
hardwoods
such as maple, oak, and sycamore, come from broad-leaved deciduous trees, which shed leaves annually. can be used for flooring, paneling, interior trim and furniture
knot
a defect in wood from a branch embedded in a tree and cut through in manufacture
peck
pitted area sometimes found in cedar and cypress
pitch pocket
opening between growth rings containing resin
shake
lengthwise grain separation between or through growth rings
check
lengthwise grain separation caused by seasoning
split
lengthwise separation of wood extending from one face to another
wane
lack of wood on the edge or corner.
warp
shrinkage distortion of a plane surface includes bow, crook, cup, and twist
yard lumber
use in general constrtuction
factory and shop lumber
is used for remanufacture into products such as sash and doors and the grades are based on the amount of clear wood in each piece.
lumber type: boards
are graded for appearance and used as siding, subflooring and trim.
lumber type: dimension and timbers
aka structural lumber and timbers are called structural lumber, used for load bearing members and graded for strength.
fiberboard
is manufactured from waste paper, wood pulp and fibers. It is used for acoustical tile, sheathing, and interior wall finishes.
flakeboard
is composed of large wood flakes bonded together with synthetic resin under pressure
particleboard
is dry formed of wood particles bonded together with synthetic resin.
beadboard
is an insulating board consisting of a core of small, expanded polystyrene beads with heavy paper laminated to both sides. Major use is an insulator material like perimeter insulation on foundation walls
plastic laminates
plastic laminates consist of a base of phenolic resin impregnated kraft paper over which a patterned sheet is applied.
glulam appearance: industrial
the grade used where appearance is not a prime concern
glulam appearance: architectural
the grade used where appearance is an important consideration
glulam appearance: premium
the top grade specified where appearance is of primary importance. it is the most expensive grade and arrives at the site fully wrapped for protection
Ferrous metals
Are those containing a substantial proportion of iron like stainless steel and galvanized iron. Require a protective coating to prevent corrosion
Non-ferrous metals
Are metals not containing substantial amounts of iron like aluminum, copper and zinc they resist corrosion.
Wrought
Products are obtained by forcibly shaping solid metal to a required form by a variety of methods for example cold rolling, forging pressing, drawing, and extruding
Cast iron
Produced by resmelting pig iron with steel scrap. It has a relatively high carbon content. It has a high compressive strength but low tensile strength
Alloy steel
This steel contains other elements added for a higher strength like nickel and chromium
Anodizing
Is a metal finish applies to aluminum which begins by inserting the material into an electrolyte. The electric current creates a coating on the aluminum
Galvanizing
The most popular protection for iron and steel. A coating of zinc is applied by immersing the steel in a bath of molten zinc
Tensile
Structures able to resist wind lift and other stresses due to their anticlastic curvature and by prestressing the fabric and steel cables. Tensile structures are transmitted through the structure to ground anchors
Surface water
Consists of ponds and other surface accumulations of water caused by rain, thawing ice, or snow
Ground wAter
Refers to the water contained in the voids and crevices under the earths surface
Rim locks
Are mounted on the interior surface of the door And have square or rectangular boxes visible
Cylinder locks
Are somewhat concealed by fitting into holes drilled in the lock stile of the door
Mortise locks
Fit completely into a rectangular cavity carved in the edge of the door
Unit locks
Fit into a door cutout and are therefore installed quickly and efficiently
Metal lath
A sheet metal or wire fabric into which a base coat of plaster is keyed. It is fabricated from copper alloy steel coated with a rust inhibiting paint or from galvanized steel.
Lathing board
Referred to as plasterboard, gypsum lath, or Gyplath is composed of gypsum that has been mixed with water hardened and dried and sandwiched between two sheets of heavy porous paper
Magnesite
Seamless floors are made from a composition of magnesium oxide, sand, and magnesium chloride which forms a plastic material that is troweled to a smooth finish
U factor
Measure of hear transmission where a low U factor has a slow heat loss or gain (brick wall) and a high U value has a rapid heat loss or gain (window)
R value
Measure of thermal resistance in a component . Used to define the level of insulation
Free water
Water held in cut lumber within the cavities of the cells. Reduces water content to 26%-32% moisture
Bound water
Water held in within the cellulose of the cell walls of wood starts to shrink at this point and the strength and stiffness of the wood begins to increase
Air drying wood
Takes several months and results in 10% to 20% moisture content
Kiln drying
Takes a few days and results in 10% moisture content
Grading
Each piece of lumber is graded for appearance or structural strength and stiffness at the mill
Stucco
Portland cement that is strong durable economical and fire resistant material
Cement
A product of lime, iron, silica, and alumina crushed, ground, proportioned and blended then sent through a kiln, cooked and pulverized to a powder
Construction joints
Horizontal or vertical joints between two successive concrete pours
Honing
Process of sanding/ polishing for a matte or slightly reflective surface
Air entrained concrete
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 causes by cycles of freezing and thawing
Coal tar enamel
Coating for anti corrosion resistant to soil bacterial, marine organisms and root growth
Alkyd
A modern synthetic resin used to replace oil in varnishes, paints and adhesives
Acrylic paint
Fast drying ; water resistant paint containing pigments suspended in acrylic polymer emulsion
Oleoresinous Paint
Naturally occurring mixture of oil and a resin extracted from pine/fir trees and thinned with a solvent
Scratch coat
Troweled on roughly and scratched while still wet using notches rage to create rough surface for second layer to bond after it hardens
Brown coat
Plaster: build strength and thickness and to present a level of surface for the application of the final application
Finish coat
Plaster: produced by drawing a long straightedge across the surface of the grounds to strike off wet plaster
Fiber saturation point
Is the moisture content above which there is no shrinking or swelling of wood
Keyed joint
A joint used between two concrete slabs in order to maintain alignment after the concrete has cured
Cohesive soil
Sticky soil whose strength depend on the strength tension of capillary water
Parging
The process in which mortar coats are trowel applied to exposes masonry basement or foundation walls. This is a strategy to control water leakage
Sherardizing
A process in which metallic zinc dust is applied under great heat.
Weathering steel
Requires no protective coating Is virtually maintenance free It ultimately weathers to a deep brown/reddish that resists corrosion
Electroplating
Employs an electric current and an electrolytic solution to deposit a metallic coating on steel
Board feet
One -twelfth of a cubic foot of lumber
Cathodes
Are stable metals not prone to corrosion
Anodes
Are less stable metals that are more likely to corrode
Deadman
Deadman is a timber, stone, or concrete mass buried in the ground as an anchor; used for retaining walls over 3; high and placed 6’ o.c.
Back-up drain
For low sloped roofs in case of clogging drain or ponding ; can be no more than 2” above roof
Back up scupper
in case of drainage failure
Pitch pan
Counter flashing allows the roof membrane to be changed without touching the coping.
Top side roof
Vents allow moisture to escape by venting the space between the roof membrane and the insulation.
Shingles
Tapered and overlapping, staggered in plan (asphalt, composition shingles); saw cut wood; attached with a pre-drilled holed and screw.
Shakes
Roof shakes are thicker than shingles; chiseled wood
Skip sheathing
Boards with intentional gaps allow ventilation under roof
Fiber breathing mat
Allows air under shingles, better equalize temperatures
Summerwood
Grows slower, more strength
Springwood
Grows faster, less strength
Hardwood
Comes from deciduous trees, used for flooring, trim, soft, more intricate, more expensive
Softwood
Comes from coniferous trees, structural lumber, uglier, coarse, tough, hard
Plainsawn lumber
Cuts made parallel to the grain, more likely to warp
Quatersawn lumber
more expensive, cut in quarters, radially, more waste
Free water
Water in wood that i first to dry, water stored in cells Once free water is gone, remaining moisture is about 30%
Fiber saturation point
About 30% moisture content
Bound Water
Held tightly in the cells, causes the shrinkage of wood
Seasoning
Drying in lumber yard, kiln drying
Gluelam
Adhering small strips of wood together, more expensive, stronger
Cross laminated timber
Alternate layers of solid timber at 90 degrees, two way strength
Laminated Strand lumber
Shredded wood strands glued , pressed together and glued - longer strands used; weakest, least expensive
Oriented Strand Lumber
Shredded wood strands glued together, shorter strand used; weakest, least expensive
Parallel Strand Lumber
Shredded lumber in the same direction and glued, cheaper, stronger, heavier, expensive
Wood I-Joist
Longer horizontal span
Laminated Veneer Lumber
Plywood sandwiched and laminated
Wood Plastic Composite
Less Likely to shrink or warp, more weather resistant , more flexible , shorter spans between teams required.
Oriented Strand Board
Long strands of wood compressed and glued; stongest and stiffest
Particle Board
Smaller fibers than OSB, under used wood veneer or plastic laminate. (furniture)
Fiberboard
Small wood fibers still with resin also limited to inter loads MDF.; interior uses
High Density Fiberboard
Hardboard; exterior siding , furniture
Low Density Fiberboard
Insulating Fiberboard sheathing; non structural
Hardwood Plywood
Maple, Burch, fine woodworking, cabinetry
Agrifiber Panels
Wheat Board, Rice Board, Straw Board, waste product
FSC
Forest Stewardship Council; Certifies wood; wood grown using sustainable practices
Creosote
Oil based, cannot be painted, bad odor and phased out
Pentachlorophenol
Oil based, cannot be painted, used on telephone poles
Chromated Copper Arsenate (CCA)
Extremely toxic, phased out in 2004
Alkaline Copper Quarternary (ACQ)
Less toxic, cannot use steel/alum. fasteners, above ground, ground contact, freshwater
Copper Boron Azole (CBA)
Less toxic, cannot use steel/alum. fasteners, above ground, ground contact, freshwater
Micronized Copper
Solid Powder, less corrosive, more natural, painted
Carbon based PTI (Propiconazole Tebuconazole Imidacloprid)
Carbon based, less corrosive, paint
Disodium Octaborate Tetrahydrate (DOT)
Used above ground, termite areas
Bright Nails
No weather protection
Hot Dipped Galvanized Nails
Weather resistant
Stressed Skin Panels
A sheathing layer on both sides of the frame
Structural Insulated Panels
Insulation with sheathing on either side, no structure
Rimboard
Band Joist; Sits on top of the header of floor below of foundation Seals the open ends of the Joist Provides surface for attachment of exterior insulation, cladding and finish elements Transfers some of the load to the floor below. After the attic this is the most likely place for insulation gaps.
Mild steel
Rolled hot, structural members , w-flange
Cold-rolled steel
Stronger form of steel, thin calling, metal studs
Cast iron
Lots of carbon, strong, brittle
Wrought Iron
Less Carbon, weak, malleable
Stainless Steel
More resistant to weathering (nickel / chromium)
I-beam
Replaced by wide flange, american standard, less sufficient
Wide-flange Beam
More sufficient, column load (square), beam load (rectangle)
Castellated beam
Deeper and Lighter
Plate Girder
Custom Shape , wide or narrow
Slip Critical Bolt
Preloaded so friction resists movement
Bearing Shear Bolt
Snug fit and movement assumed.
Back-up Bars
Prevents the welding arc from burning through the flange
Dog bone cuts
Deforms so that there is no catastrophic failure of the the weld or bolts
Fully restrained Moment Connection
Have sufficient strength to transfer moments with negligible rotation between connected members.
Partially Restrained Connection
Have sufficient strength to transfer moments with rotation between connected members
Tag line
Rope attached to a member to assist the member into designated position.
Concrete
Composed of Portland cement, aggregate (gravel +sand), water.
Vermiculite
Expanded mica
Perlite
Expanded volcanic rock, allows for lighter / weather concrete, more insulation
Workability agents
Easier to work, in forms and easier to finish, includes air-entraining , fly ash, and organic compounds
Air entraining Admixtures
Increases workability of the concrete and reduce freeze and damage (air pockets allow expansion) lightweight, nonstructural.
Water reducing Admixtures
Less Water needed with the same workability, less water means high strength.
Superplasticizers
organic, increased workability and easier flow into forms, convoluted forms and allow reduced water content and maintain workability
Accelerating Admixtures
Cures Faster
Retarding Admixtures
Slows down the curing to extend the workability
Shrinkage -Reducing Admix.
Reduce shrinkage and therefore cracking.
Corrosion Reducing Admix.
Reduce rusting of rebar, like if exposed to road salt
Freeze Protection Admix.
Concrete can cure as low as 20 degrees
Extended set control Admix.
Delays curing for up to Several days , stabilizer added , when mixing the batch which puts off the curing until activator is added.
Self Consolidating Concrete
Smaller aggregate and pourability needed to fill in voids, used to make clean edges
Fly Ash
Reduces the embodied energy of concrete by 1/3 More dense, stronger, shrinks less, sulfate resistant, decreased permeability.
Stirrups
Resist the modest diagonal forces
Reinforcing bar couplers
attach to rebars together end to end
Chairs
Keep rebar at the proper height.
Bolsters
Combination of chairs
Shrinkage Temperature Bars
Helps reduce concrete shrinkage during curing (slabs)
Vertical Bars
Handle compressive loads, tensile loads (wind / seismic)
Ties
Prevent outward buckling
Dowels
Helps tie the concrete wall to the concrete footing.
ICF (Insulating Concrete Forms)
Made of polysytrene and used for insulation
Water struck brick
soft mud brick process (20% - 30% water), pressed into molds, labor intensive, custom
Stiff mud process
Least expensive, least labor intensive, most homogenous
Firing Process
Takes between 2 days and a week
Periodic Kiln
Bricks are moved into the kiln for a week and 2 days until the next load
Tunnel Kiln
Continous train of bricks move through kiln
Exterior Clamp Bricks
Burned , not distorted suitable for exterior application; manufactured on site.
Undercover clamp Bricks
Not sufficiently water resistant, used in back up wythes
Hollow Bricks
used when the voids are filled w/ reinforcing bars and grout; 40% solid
Frogged Brick and Cored Brick
Considered solid; greater than 75% solid;
Grout
More fluid and pourable than concrete
Low Lift Grouting
Pours grout 4 feet at a time, partially cures then pours next load
High Lift Grouting
Taller reinforced wall , some bricks placed at end for access to clean the cavity
Paving Bricks
Used for Horizontal surfaces, superior freeze than resistance, lower water absorption rate
Fire Bricks
Superior fire resistance, uses a special fire clay mortar and thinner joints
Granite
Igneous, hardest, strongest, and nonporous , most permanent of building stones, fine, medium or coats stone.
Limestone
Sedimentary, porous and weakest of building stones, continuous quarry, four grades, select, can deteriorate, non polluted areas
Quartz Group
Sedimentary, includes sandstone, brownstone, and blue stone
Slate
Metamorphic, comes from clay, has planes of cleavage, good and polished, good for paving, roof shingles, and thin wall facings
Marble
Metamorphic, comes form limestone, easily carved and polished, can be cut as thin as 3/4”
Stone Masonry
Stacked with mortar
Stone Cladding
Attached to a building w/ anchors
Lewis Pins
Used to lift stones
Strap Anchor
Anchor mortar to wall
Box Lewis
Alternate form to lewis pin
Dry Stacked Masonry Wall
Surface bounded masonry, conc. blocks stacked w/o mortar covered w/ stucco
Blower Door
Tint canvas with a fan which pressurizes the building
Membrane Fluttering
Loose sheets are lifted up and down from air changes
Expanded Polystyrene
Cheaper and easily worked in the field, water and air tolerant
Extruded Polystyrene
More insulate per inch; water and air tolerant
Polyisocayanurate
Cannot be exposed to moisture, underground, air barrier
Closed-cell Spray foam
Continuous, waterproof, well underground, air barrier
Open-cell spray foam
Interior only, non-air or water barrier, noise insulator, cheaper
Glass-fiber insulation
Comes in semi-rigid exterior versions, cheaper, fire resistant, may act as capillary break drainage plane
Mineral Wool
Inexpensive, can be a drainage plane, fire-resistant; may act as capillary break drainage plane
Welding
Joining two metals by heating them above their melting points
Soldering
Joining two metals using lead based or tin based alloys as filler metals that melt below 500 degrees.
Scribe
An integral part of woodwork or a separate piece of trim that is cut, sanded, or otherwise shapes on the job site to exactly match the irregularity of an adjacent material.
Perm rating
A measurement of how much moisture passes through a certain material in a given amount of time.
Rabbet
The space in which the door closes in a door frame
Annealed glass
Standard glass used in most non critical glazing situations
Emissivity
is a measure of the efficiency in which a surface emits thermal energy. It is defined as the fraction of energy being emitted relative to that emitted by a thermally black surface (a black body). A black body is a material that is a perfect emitter of heat energy and has an emissivity value of 1. A material with an emissivity value of 0 would be considered a perfect thermal mirror.
High Emissivity = cooler roof
Pozzolans
Pozzolans combine with the lime to produce additional calcium silicate hydrate, the material responsible for holding concrete together. By consuming the excess lime:
The strength of the concrete is increased
Its density is increased
Efflorescence is decreased
The propensity for alkali-silica reaction (reaction with glass) is decreased, or even virtually eliminated
Creep
deformation of structure under sustained load. Basically, long term pressure or stress on concrete can make it change shape. This deformation usually occurs in the direction the force is being applied.
Frie Otto
Frei Paul Otto (German: [ˈfʁaɪ ˈɔtoː]; 31 May 1925 – 9 March 2015) was a German architect and structural engineer noted for his use of lightweight structures, in particular tensile and membrane structures, including the roof of the Olympic Stadium in Munich for the 1972 Summer Olympics.
Cold Roof Air Gap
In a cold climate, the primary purpose of ventilation is to maintain a cold roof temperature to avoid ice dams created by melting snow and to vent any moisture that moves from the conditioned living space to the attic.
EIFS
is a general class of non-load bearing building cladding systems that provides exterior walls with an insulated, water-resistant, finished surface in an integrated composite material system.
GFRC (Glass Fiber Reinforced Concrete)
is a type of fiber-reinforced concrete. Are mainly used in exterior building façade panels and as architectural precast concrete. It can be effectively used to create façade wall panels, fireplace surrounds, vanity tops and concrete countertops due to its unique properties and tensile strength. The high dose of glass fibers leads to high tensile strength while the high polymer content makes the concrete flexible and resistant to cracking. Proper reinforcing using scrim will further increase the strength of objects and is critical in projects where visible cracks are not tolerable.
Pantheon
Romanesque
Hagia Sophia
Simple, Symmetrical
Palladio - Villa Rotunda
Simple, Symmetrical
oxidization
to take away hydrogen, as by the action of oxygen; add oxygen or any nonmetal.
tarnish
is a thin layer of corrosion that forms over copper, brass, silver, aluminum, magnesium and other similar metals as their outermost layer undergoes a chemical reaction.
Calcium Chloride
is the most effective and least expensive cold weather accelerator for concrete
