Chapter 2 Concepts Of Construction Flashcards
Arch
Combines the function of a beam and a column.
Attitude
Vertical or horizontal orientation.
Axial load
A load that passes through the centroid of a section under construction and is perpendicular to the plane of the section.
Bar joist
Lightweight steel truss joist.
Beam
A structural member that transmits forces perpendicular to such forces to the reaction points.
Bent
A line of columns in any direction.
Braced frame
A structural system that uses diagonal members to provide bracing against the lateral wind and earthquake loads.
Bracket
Diagonal member that supports what would otherwise be a cantilever.
Brick and block composite wall
Consist of an exterior wythe of brick directly mortared or parged to an inner wythe of concrete masonry unit (CMU).
BTU
British thermal unit; the quantity of heat required to raise the temperature of 1 pound of water 1°F at the pressure of 1 atm and temperature of 60°F.
Built-up girder
Made of steel plates and angles riveted together, as distinguished from one rolled from one piece of steel.
Buttress
Mass of masonry built against a wall to strengthen it. Necessary when a vault or an arch places a heavy load or thrust on one part of a wall.
Caloric value
Measured in BTU; the amount of heat required to raise 1 pound of water 1°F.
Camber
Upward rise.
Cantilever beam
A beam supported at one end only, rigidly held in position at that end.
Cantilevered
Supported by cantilever.
Cavity or hollow wall
A wall built of two wythes (a single vertical thickness of masonry) separated by a space for rain drainage or insulation.
Centroid
The center point at which a body would be stable, or balanced, under the influence of gravity.
Chord
The outside members (top and bottom) of a truss, as opposed to the inner “webbed members.”
Column
A structural member that transmits a compressive force along a straight path in the direction of the member.
Composite
Built up of different parts, pieces, or materials.
Composite wall
A wall composed of two or more masonry materials that react together under load.
Compression
Direct pushing force, in line with the axis member; the opposite of tension.
Concentrated load
A load acting on a very small area of the structures’s surface; the exact opposite of a distributed load.
Continuous beam
A beam supported at three or more points. It is considered structurally advantageous because if the span between two supports is overloaded, the rest of the beam assists in carrying the load.
Core construction
No external braces involved; bracing is done within the core of the structure.
Cross wall
Any wall at right angles to any other wall; the walls should brace one another.
Dead load
The weight of a building; the dead load consist of the weight of all materials of construction incorporated into the building, including but not limited to walls, floor, roofs, ceilings, stairways, built-in partitions, finishes, cladding, and other similarly incorporated architectural and structural items, as well as fixed service equipment, including the weight of cranes.
Deflection
The deformation or displacement of a structural member as a result of loads acting on it.
Demising wall
Wall bounding a tenant space.
Diaphragm floor
A floor designed to stiffen a building against wind and other lateral loads such as earthquakes.
Eccentric load
A force that is perpendicular to the plane of the section but does not pass through the center of the section.
Fire cut
The end of a joist that is cut at an angle to permit the joist to fall out of a wall without damaging the load-bearing wall.
Fire load
The potential fuel available for a fire in a building.
Fire resistance
The ability of a material to avoid ignition, combustion, and the thermal effects of fire.
Fire wall
Wall with a fire-resistive rating and structural stability that separates buildings or subdivides a building to prevent the spread of fire.
Fixed beam
Beam supported at two points and rigidly held in position at both points. This rigidity may cause collapse of a wall if the beam collapses and the rigid connection does not yield properly.
Flitch plate girder
Made by sandwiching a piece of steel between two wooden beams.
Foundation
The lower division of a building that serves to transmit and anchor the loads from the superstructure directly to its earth or rock, usually below ground level.
Gang nail
Another name for a gusset plate in a lightweight wood truss.
Girder
A beam that supports other beams.
Gravity connection
A connection that depends on the weight of the building to hold it in place.
Gravity resistance system
All of the structural elements of a building and the connections that support and transfer the loads.
Grillage
A series of closely spaced beams designed to carry a particularly heavy load.
Gusset plate
(Lightweight wood truss) Connecting plate made of a thin sheet of steel used to connect the components of the truss.
Header
A masonry unit that overlaps two or more adjoining wythes of masonry to tie them together.
Heat release rate (HRR)
The rate at which the potential heat in a fuel is released.
Homogeneous
When describing wall construction, a wall that acts as one unit (good bonding exist between bricks blocks, and mortar.
Hurricane bracing
Components of a hurricane resistance system that prevent uplift of the components of a structure, including galvanized steel straps used to connect roof trusses to stud walls and anchor bolts use to connect stud walls with sill and sole plates.
Impact load
The effect of a moving load upon a stationary structure.
Inverted king post truss
A truss incorporating a single compression member; it is inverted because the compression member extends downward.
Joist
A beam.
K-bracing
An arrangement of braces between columns that resembles the letter “K.”
Kilojoule (kJ)
Metric unit approximately equivalent to one BTU.
Kilowatt (KW)
A unit for measuring the energy release rate of a fire.
KIP
1000 pounds force.
Knee wall
A wall typically found in the top floor of a wood-frame home with a peaked roof. This short wall “squares off” the triangular area at the edge of the room where the sloping roof meets the floor.
Lateral impact load
A force that acts on a structure from a horizontal direction, such as wind or seismic forces.
Ledger board
A wood board typically attached to a wall’s studs that is used to support wood joists.
Lightweight truss
A collection of lightweight structural components joined in a triangular unit that can be used to support either floors or roofs.
Lintel
The horizontal beam that forms the upper structural member of an opening for a window or door and supports part of the structure above it.
Live load
The weight of the building contents.
Load
Force or other action that results from the weight of all building materials, occupants and their possessions, environmental effects, differential movement, and restrained dimensional changes.
Load-bearing wall
Any wall that carries a load in addition to its own weight.
Megastructure
A very large structure.
Megawatt (MW)
A unit for measuring the energy release rate of a fire.
Moment
The tendency of a force to rotate or twist a structural member.
Moment frame
A structural system that utilizes special “moment” connections between columns and beams to resist rotation due to lateral loads such as earthquakes and wind.
Monolithic concrete
A construction technique in which all successive poured concrete castings are joined together so that the structure seems to be like one piece of stone.
Needle beam
When any change is to be made in the foundation of an existing wall, the wall must be supported. Often holes are cut through the wall, and so-called needle beams are inserted and supported on both sides. They pick up the load of the walls.
Neutral axis
The line along with the length of the beam does not change.
Non-load-bearing wall
A wall supporting no load other than its own weight.
Overhanging beam
A beam that projects beyond its support, but not far enough to be a cantilever.
Panel points
The connection points joining ties, struts, and chords in a trust.
Panel wall (curtain wall)
Non-load-bearing enclosing wall on framed buildings.
Parallel-chord truss
A truss in which both the upper and lower chords are parallel to each other.
Partition wall
A non-load-bearing wall that subdivides spaces within any story of a building or room.
Party wall
A load-bearing wall that is common to two structures.
Pier
A short column of masonry, usually rectangular in horizontal cross section, used to support other structural members.
Pilaster
A masonry column projecting from one or both faces of the wall in which it is located.
Pinned
A description for structural elements that are connected by simple connectors such as bolts, rivets, or welded joints.
Plastic design
Design based on connections that redirect overloads to other sections of the building.
Portal bracing
Heavy riveting of girders to columns from the top to the bottom of the frame.
Precast
A concrete member that is cast and cured in a place other than its final position in the structure.
Precast concrete tilt slab wall
A type of wall that acts as a vertical cantilever when it is being erected and is braced by tormentors or temporary bracing polls.
Q
A designation of the HRR; refers to the rate at which a fuel burn.
Queen post truss
A truss with two compression members.
Rakers
Diagonal bracing columns.
Reaction
The response in structures to the imposed loads, which are generally developed at the supports.
Reinforced concrete
In concrete masonry construction, steel reinforcement that is embedded in such a manner that the two materials act together in resisting forces.
Repeated load
A load that is applied intermittently.
Rigid frame
Structural frame in which all columns and beams are rigidly connected. There are no hinged joints, and the angular relationship between beam and column members is maintained under load.
Rising roof
A phenomenon in wood trusses in which differences in moisture levels between the upper and lower wood truss chords cause the truss to bend and create a rise in the roof.
Rubble masonry wall
A wall composed of inner and outer wythes of coursed masonry. The space between the wystes is filled with random masonry, sometimes mixed with mortar. Such walls are unstable to a lateral thrust.
Safety factor
The ratio of the strength of the material just before failure to the safe working stress.
Sand-lime mortar
A water-soluble mixture used in the past as mortar; when water is applied, the mortar can be washed away from the wall.
Self-releasing floor
A type of floor in which floor girders are set on anchor boxes in walls and caps attached to columns. A wood cleats or steel dog-iron similar to a big staple is used to provide minimal stability. Often used in heavy-timber construction.
Self-weight
Another term for dead load.
Serpentine wall
A curving wall.
Shear
Forces occurring within a building member when opposing forces pull the member in opposite directions.
Shear wall
A wall that counteracts the effects of lateral loads such as wind and earthquakes.
Simple beam
A beam supported at two points near its ends. In simple beam construction, the load is delivered to the two reaction points and the rest of the structure renders no assistance in an overload.
Spaceframe
A three-dimensional pyramid like truss.
Spandrel girder
A girder that ties wall columns together in a framed building.
Steel joist
And open web design used for the support of floors and roofs.
Stiffness
A capacity of a member or framework to resist imposed loads without excessive deflection.
Strain
The actual percentage of elongation (deformation) when a material is stressed.
Stress
Force per unit area that produces a deformation.
Stretcher
A masonry unit laid horizontally with its length in the direction of the face of the wall.
Structural elements
Components of a structure that include beams, trusses, columns, arches, and walls.
Structural frame
All members of the structure that are tied together to carry the imposed loads to the substructure, and hence to the ground.
Strut
A bracing column.
Suspended beam
A simple beam, with one or both ends suspended on a tension member such as a chain, cable, or rod.
Suspended load
A hanging load supported from above.
Tension
A pulling or stretching force in line with the axis of the body; the opposite of compression, which is pushing, crushing stress.
Tie
(truss member) The tensile connecting members of a truss web.
Tie rod
A rod in tension; used to hold parts of a structure together.
Torque
The measurable turning force applied to a structural member.
Torsion
A force tending to twist a structural member.
Transfer beam
A beam that typically carries a load around a large opening or over an area in order to avoid intervening columns.
Transmission
The manner in which a load is spread from the point of application to the ground.
Triangular truss
A roof truss that is triangular in shape; it is used to create a peaked roof.
Truss
A type of beam that is a framed structure consisting of a triangle or group of triangles arranged in a single plane in such a manner that loads applied at the points of intersections of the members will cause only direct stresses (tension or compression) in the numbers.
Tube construction
Externally braced structure.
Ultimate strength
The highest load that a member or structure can sustain before failure occurs.
Uniformly distributed load
A load that is applied evenly over an area.
Veneer wall
A wall made up of a single vertical thickness of masonry that is designed to improve the exterior appearance of a building.
Vierendeel truss
A rectangular truss with very rigid corner bracing.
Voussoir
A wedge-shaped block whose converging sides radiate from a center, forming an element of an arch or vaulted ceiling.
Wall
A structural element that transmits to the ground the compressive forces applied along the top or received at any point on the wall.
Wall column
A column of steel, reinforced concrete, or solid masonry (such as brick or solid block) in a block wall. Concentrated loads such as main girders are applied to all the wall directly above the wall column.
Watt (W)
A unit for measuring the energy release rate of a fire.
Web
The group of struts, ties, and panel points in a truss.
Weep hole
A drainage hole in a masonry wall that allows water trapped inside the wall to escape.
Wet joint
Cast-in-place concrete that unites the rods projecting from precast sections.
Wind load
The positive or negative force of the wind acting on a structure.
Wythe
A single continuous vertical wall of masonry units (one masonry unit in thickness).
