02 Terms of Construction and Building Design Flashcards
Active Fire Protection
Automatic sprinklers AND FFs hose streams
Arch
A curved masonry structure used as a support over an open space
Balloon Construction
(1/3 basic methods of residential construction)
Studs extending continuously from the structure’s foundation sill to the top plate near the attic.
During collapse, walls fall out at 90-degree angles. If bearing wall collapses, it can cause second collapse of the floors it supports.
Beams
A beam is a horizontal structural member, subject to compression, tension, and shear, supported by one of three methods.
Cantilever Beam Support
A beam supported or anchored at only one end, which is considered a collapse hazard during fire exposure.
Least amount of structural stability
Continuous Beam Support
A beam supported at both ends AND at the center.
Greatest structural stability
Simple Supported Beam
A beam supported at both ends.
Braced-Frame Construction
(2/3 basic methods of residential construction)
A.K.A. Post-and-girt
Vertical members called posts reinforce each of the four corners of the structure, and horizontal timbers called girts reinforce each floor level.
Connected by fastenings call Mortise-and-Tenon joints.
Walls fail in an inward/outward collapse.
Bridge Truss
A perpendicular truss used is steel bar truss floor systems to provide lateral stability.
See purlin
Buttress
A wall reinforcement of a brace built on the outside of a structure.
Pilaster
A buttress constructed on the INSIDE of a wall.
Cold-formed Steel Beam
A sheet steel C-beam used in lightweight steel floor construction
Collapse
The failure of any portion of a structure during a fire
Curtain-Fall Wall Collapse
(1/3 Masonry wall collapse)
It occurs when an exterior masonry wall drops like a falling curtain cut loose at the top.
Inward/Outward Collapse
The collapse of an exterior wall that breaks apart horizontally. The top collapses inward, back on top of the structure; the bottom collapses outward on to the street.
- Wood-braced-frame-constructed buildings
- Timber truss roof collapse can cause a secondary collapse of a front wall in this manner
Lean-Over Collapse
The type of a woof-frame building collapse indicated by the burning structure slowly starting to tilt or lean over to one side
Lean-To Floor Collapse
A floor collapse in which one end of the floor beams remains partially supported by the bearing wall, and the other end of the floor beams collapses n to the floor below or collapses but remained unsupported.
Ninety-Degree-Angle Wall Collapse
A type of burning building wall collapse. The wall falls straight out as a monolithic piece at a 90-degree angle
Pancake Floor Collapse
The collapse of one floor section down upon the floor below in a flat, pancake-like configuration. When floor beams pull loose or collapse at both ends, a pancake collapse occurs.
Secondary Collapse
The collapse of portions of burning taller structures on to smaller structures, causing the collapse of the smaller building
Tent Floor Collapse
A floor collapse in the shape of a tent.
V-Shaped Floor Collapse
The collapse of a floor at the center of the floor beams. The broken center of the floor section collapses down and both ends of the floor section remain partially supported
(Basically, the opposite of Tent Floor)
Column
A vertical structural member subject to compressive forces.
Columns and bearing walls are parts of the what?
Vertical framework
Girders and beams are parts of the what?
Horizontal framework
Primary Structural Members
Bearing Walls, Columns, Girders, Ridgepoles, Hip Rafters, Headers, and Trimmer Floor Beams
Convenience Stair
An opening in a floor slab for a stair between floors. Sometimes called an access stair.
Coping Stone
The top masonry tile or stone of a parapet wall, designed to carry off rainwater. Sometimes called a
“capstone.”
Weighs between 5 and 50 pounds.
Corbel
A bracket or extension of masonry that projects from a masonry wall.
A corbel used on the inside of a masonry wall to support a beam is called a “corbel ledge” or “corbel shelf.”
Corner Safe Areas
Four Flanking zones around a burning building
Deck
A horizontal surface covering supported by a floor or a roof beam.
Deflection
A bend, twist, or curve of a structural element under a load.
Facade
The front or face of a building. A facade includes four collapse dangers - a marquee, a cornice, a canopy, and a parapet wall.
An ornamental facade parapet wall with a decorative stone corbel coping is one of the most unstable walls a FF will encounter
Fire Cut Beam
A gravity-supported beam end designed to release itself from the masonry wall during a collapse
Fire Load
The measure of maximum heat release when all combustible material in a given fire area is burned. The content and structure of a building contribute to fire load.
Fire Resistance Rating
A relative rating to indicate in hours how long a wall, floor, ceiling, beam, or column will sustain performance during a fire.
Fluted Metal (Steel) Deck
A wavy piece of sheet steel deck used to support concrete floor. Sometimes called a corrugated metal deck.
Force
The cause of a motion, a change in motion, or a stoppage of motion.
An external force is a load (dead, live, wind, impact)
An internal force is a stress (compressive, tension, or shear)
Frame Tube Construction
Tubular hollow exterior bearing walls
Girder
A structural element that supports a floor or a roof beam.
Global Collapse
A total collapse of a building
Gravity Load
A combination of dead and live loads
Gusset Plate
A metal fastener
- 1/4 in think sheet
- Many small, triangular holes punched through it
- “Nails” are only 1/2 inch long
Hat Truss
A means of load distribution connecting core columns and perimeter columns.
Header Beam
A support used to reinforce an opening in the floor of a wood-frame, ordinary, or heavy timber building.
Hierarchy of Building Elements
Most to Least:
Bearing Wall
Column
Girder
Beams, floor, and roof
Deck
I-Beam
A wood or steel I-beam consists of a center called a web section and a top and bottom flanges.
Joist
A piece of lumber used as a floor or roof beam. The terms joist, beam, and rafter are used interchangeably.
Interstitial Space
A concealed space between floors used to contain large mechanical and electrical equipment
This is also called a plenum space.
Kip
One kip equals 1,000 pounds.
KSI is the abbreviation for kips per square inch
Laminated Beam
A glued or layered composition beam
Lintel
A horizontal piece of timber, stone, or steel placed over an opening in a wall. The lintel is a load-bearing structural element that supports and redistributes the load above the opening.
Loads
Forces acting upon a structure. The loads which can cause a collapse during a fire are dead loads, live loads, impact loads, and fire loads:
Axial Load
(1/3 Imposed Loads)
An axial load passes through the center of a structure and is the most efficient manner by which a load can be transmitted through a structural support like a column or a bearing wall.
Concentrated Load
A load applied at one point or within a limited area of a structure.
Dead Load
One of the five major loads that must be considered in the design of a building. A dead load is a static or fixed load created by the structure itself and all permanent equipment within.
Eccentric Load
(2/3 Imposed Loads)
A load transmitted off-center or unevenly through a structural member.
Impact Load
A load applied to a structure suddenly, such as a shock wave or a vibrating load.
Lateral Load
Any type of load applied to an upright structure from a direction parallel to the ground. (Examples: wind, tips of ladders , horizontal explosion shock waves, hose stream)
Live Load
A transient or movable load, such as a building’s content, occupants, FFs, fire equipment, or water
Torsional Load
(3/3 Imposed Loads)
A load that creates a twisting stress on a structural member. When a large steel girder collapses at one end, the other end experiences a torsional or twisting stress.
Load Stress
An internal stress created by a load in a structural element, including compression, tension, and shear stresses.
Mortise
A structural connection often used in braced wood-frame construction, it is a hole cut into a timber that receives a tenon.
Open-web steel bar joist
A lightweight steel truss used as a floor or roof beam.
An unprotected open-web steel bar joist can collapse after 5 to 10 minutes of fire exposure.
Passive Fire Protection
The fire containment provided by a structure is considered “passive” fire protection.
Partition walls of spray on fire retarding and fire resistive construction are examples
Pilaster
A masonry column bonded to and built as an integral part of the inside of a masonry wall.
Platform Wood-Frame Construction
(3/3 basic methods of residential construction)
One complete level of 2x4 wood enclosing walls raised and nailed together; the floor beams and deck for the next level are constructed on top of these walls.
Primary Structural Member
A structure that supports another structural member in the same building, such as a bearing wall, a column, or a girder.
Progressive Collapse
When initial structural failure spreads from structural element to structural element resulting in teh collapse of an entire structure or a disproportionately large part of it.
Purlin
A timber laid horizontally perpendicular to support the common rafters of a roof.
Restrained Beam End
A welded, nailed, bolted, or cemented end of a floor or roof beam. It is one of two methods of supporting a beam end, the other being an unrestrained beam.
Ridgepole
A horizontal timber that frames the highest point of a peak roof. Roof rafters are fastened to the ridgepole.
Roof
The sheltering structure of a building that protects the interior spaces from natural elements
Safety Factor
The quotient of the load that will cause a structure to collapse divided by the load a structure is designed to support.
Most structural elements are designed with a safety factor of 2 or more.
Stress
A force exerted upon a structural member that strains or deforms its shape. The term stress and load are often used interchangeably.
Compression (1/3)
A force pressing or squeezing a structure together.
Shear (2/3)
A stress causing a structure to collapse when contacting parts or layers of the structure slide past one another.
Tension (3/3)
Stress placed on a structural member by the pull of forces causing extension. Tension is the opposite of compression.
Sprayed Fire-Resistive Material
Spray-on fire-retarding material must cover the steel entirely, must be of proper thickness and/or density, and must adhere to the steel and not flake off when exposed to air movement in a HVAC plenum area.
Suspended Ceiling
A ceiling built several inches or feet below the supporting roof or floor beams above.
The concealed space above the ceiling is sometimes called a “cockloft.”
Tenon
A projecting, reduced portion of a timber designed to be inserted into the mortise hole of another timber.
Terrazzo
A polished floor covering made of small marble chips set in several inches of cement.
It is a collapse hazard - it adds weight to floor beams, conceals the heat of a serious fire below, and, because it is watertight, allows water to accumulate and built up to dangerous proportions
Timber
Wood larger than 2x4
Trimmer Beam
A wood beam constructed around the perimeter of a floor opening. A trimmer beam supports the header beam, which in turn supports the tail beams.
Truss
A braced arrangement of steel or wood-frame work made with triangular connecting members.
Unrestrained Beam End
A beam end resting on a support, held in place only by gravity
Walls
There are 9 types of walls
Walls: Area Wall
A freestanding masonry wall surrounding or partly surrounding an area (Masonry fence)
Walls: Bearing Wall
An interior or exterior wall that supports a load in addition to its own weight. Part of the skeletal framework of a structure, it most often supports the floors and roof of a building.
Walls: Demising Wall
A partition wall that extends from floor slab to floor slab above.
Walls: Fire Wall
A nonbearing, self-supporting wall designed to prevent the passage of fire from one side to another.
The fire wall must be independent of the roof structures on either side and be designed to withstand complete collapse of a structure on either side.
Walls: Freestanding Wall
A wall exposed to the elements on both sides and the top, such as a parapet wall, a property-enclosing wall, an area wall, and a newly constructed exterior wall left standing without roof beams or floors.
Walls: Parapet Wall
Parapet walls are considered freestanding walls.
One-story shopping center structures with large show windows often have parapet walls resting on steel lintels.
Walls: Party Wall
A bearing wall that supports floors and roofs of two buildings.
Walls: Spandrel Wall
That portion of an exterior wall between the top of one window opening and the bottom of another.
Wall: Veneer Wall
A finished or facing brick or stone wall used on the outside of a building. A veneer wall is fastened to a backing wall by sheet metal ties or cement.
Wall Hierarchy
A scale of wall stability during destruction by fire, based upon the stability of a wall rated by the number of interconnections the wall has with the structure
Zone of Danger: Horizontal Collapse Zone
The horizontal measurement of the wall. When establishing a collapse zone, FF should estimate this measurement in addition to outward area that the wall may cover if it falls.
Zone of Danger: Vertical Collapse Zone
The expected ground area that a falling wall will cover when it collapses.
A FD collapse zone of danger may require FFs to be away from a dangerous wall a distance equal to the height of the wall; or a distance equal to one and one half, or two times the height of the wall.
