Ch 2 Essential Bldg Concepts Flashcards
A load that is applied within any small area or at one point
Concentrated load
A moving or SUDDEN load applied to a building, and a focused or short time interval. For example, wind, large crowds, and fire stream water.
(Not dynamic)
Impact load
Loads that are transient or intermittently applied (like people on an escalator)
Repeated load
A constant load that rarely moves
Static load
Atmospheric loads that stress a building
Wind/snow load
______ are static and dynamic weights that come from the building itself, and anything that is placed within or acts upon a building
Loads
Loads can be imposed three ways
- Axial
- Eccentric
- Torsion
This load is imposed, off-center, causing a material to want to bend
Eccentric load
This load is imposed in such a way that causes a material to twist
Torsion load
Load is imposed through the center of the material
Axial load
Imposition of loads on a given material causes stress within the receiving material. These stresses are called _____
Forces
A stress that causes a material to flatten or crush
Compression
A stress that causes material to pull apart or stretch
Tension
(strEtch - tEnsion)
A stress that causes a material to tear or slide apart
Shear
Cold drawn steel like cables, bolts, rebar and lightweight fasteners loses ______ percent of its strength at ______ degrees
55% of its strength at 800°F
Hot rolled structural steel used for beams and columns, loses _____ percent of its strength at _____ degrees
50% of its strength at 1100°F
At 1000°F a ______ foot structural steel beam can elongate ______
- 100 ft
- 10 inches
Four types of reinforced concrete
- Monolithic
- Pre-tensioned
- Post-tensioned
- Precast
Often called the original engineered wood product. It is made from layering sheet veneers of wood such the green directions alternate 90° with each layer. Emits a toxic smoke and has been replaced with a true engineered wood product – OSB.
Plywood
This wood sheathing is made from COARSE SAWDUST and glue. Appears very smooth and has no wood grain. The sheeting choice for the pyrolyizing fuel source in flashover simulators
Particle board
The wood paneling used to finish interior walls or the outside of cabinets. Not intended to resist loads and are merely decorative ranging in thickness from 1/8 inch to 3/8 inch.
Decorative sheathing
The wood used to make ____ is typically derive from new growth forests and rapid growth tree farms
Engineered wood products (EWP)
A sheathing that is formed with wood shavings and a urea formaldehyde adhesive, oriented such that the grain directions are randomly oriented and layered (most prolific)
Oriented strand board
To make this product, thin sheet veneers of native wood are stacked with grains aligned and then glued with a phenolic resin. It is used in place of cut lumber for beams. It is designed to have the load imposed axially and perpendicular to the grain.
Laminated veneer lumber (LVL)
This is a structural composite lumber, manufactured from flaked and chipped strands of native wood blended with adhesive. It mostly uses strands oriented in a parallel fashion (also known as parallel strand lumber – PSL).
Laminated strand lumber
This is an engineered wood product using several layers (3 to 7 or more) boards that are layered crosswise (typically rotated 90°) and glued. This is used as a structural element for columns (much like a glulam is used for beams). A structurally sound form of plywood but thicker.
Cross laminated timber (CLT)
For every 1 ton of wood, it takes ___ times more ENERGY to produce one ton of concrete, _____ times more ENERGY for 1 ton of steel and ____ times more ENERGY for 1 ton of aluminum.
5 concrete
24 steel
126 aluminum
(CSA 546)
This is comprised of multiple layers of dimensional timber, bonded together with moisture resistant adhesives, and is a more modern form of the traditional glulam heavy timber. It can be used as horizontal beams and vertical columns, and can be produced in curved shapes.
Glued laminated timber (GLT)
Advantages of using engineered wood products over solid wood (4)
- Greater strength and stiffness
- Pound for pound strength that is greater than steel
- More efficient use of wood
- Conformance to emerging Green considerations
Four basic types of adhesive that are used in engineer wood products
- Urea formaldehyde
(most common) - Phenol formaldehyde
- Melamine formaldehyde
- Methylene diphenyl
diisocyanate (expensive)
Hot rolled steel is often called ____ and cold rolled steel is called ___
Extruded steel
Cut or rolled steel
The most common material used for building a masonry wall
Concrete masonry unit (CMU)
Some call it a cinder block
Difference between thermoplastics vs thermosetting
Thermoplastics CAN be reshaped
ThermoSETting if reheated will break down
The primary reason why firefighters must keep abreast with technology and resultant changes in bldg construction
The expanding use of COMPOSITES for many types of building materials
Fire officers need to learn a certain language used in the building construction field, which helps with: (3)
- Teach new
firefighters - Prepare more complete
prefire plans - Interact with building
representatives and
engineers during
incidents
A firefighter team making a panel cut on a pitched roof for heat ventilation can be classified as what types of loads?
- Live
- Impact
- Distributed
Two loads that exist within every building:
- Live
- Dead
5 factors that determine the suitability of the material for a given application (help them work or fail)
- Type
- Shape
- Orientation or plane
- Mass
- Material surface
Today’s sawn lumber is known as ____ as opposed to yesteryear’s ____.
- Nominal
- Full-dimensional
Decorative sheathing can range in thickness from ___ to ___
1/8 in to 3/8 in
From a fire service viewpoint, steel has two weaknesses:
- Engineered for very
specific applications - Softens and elongates
when heated
The most abundant metal that exists on Earth
Aluminum
Steel is resistant to which forces
- Tension
- Compression
- Shear
The masonry wall’s Achilles heel is the ____.
Mortar
The weight of the building itself, and anything permanently attached to the building
Dead load
Any load applied to a building other than dead loads, which are typically transient, moving, impacting or static (like furniture)
Live loads
A load spread over a large surface area or over multiple points
Distributed
