Structural terms

Building frame system

-complete space frame supporting gravity loads, lateral loads resisted by shear walls/braced frames either on exterior or interior

Curtain wall

1. In a tall building of steel-frame construction, an exterior wall that is non-loadbearing, having no structural function; also see metal curtain wall. 2. In ancient fortifications, an enclosing wall or rampart connecting two bastions or towers.

Tie beam

1. On individual pile caps or spread footings which are eccentrically loaded, a beam (usually of reinforced concrete) used to distribute horizontal forces to other pile caps or footings; a strap, 2. 2. In roof framing, a horizontal timber connecting two opposite rafters at their lower ends to prevent them from spreading; also see collar beam.

Stirrups

1. Same as hanger. 2. A bent rod, usually U-shaped or W-shaped; used in reinforced brick or concrete construction. 3. A reinforcing device to resist shear and diagonal tension stresses in a beam. 4. A metal seat, attached to a wall beam or post or hung from a girder, to receive and support a beam or joist.

Creep

1. The continuing, time-dependent part of strain resulting from stress; the permanent and continuing dimensional deformation of a material under a sustained load, following the initial instantaneous elastic deformation. 2. Slow movement of rock debris or soil, usually imperceptible except in observations of long duration. 3. In structures, particularly of concrete, permanent deflection of structural framing or structural decking resulting from plastic flow under continued stress. 4. In roofing, permanent elongation or shrinkage of a roofing membrane resulting from thermal or moisture changes. 5. The flow of water along the interface between a structure and the surrounding soil or rock foundation.

Capillarity

1. The movement of a liquid in the interstices of soil or other porous material, as a result of surface tension. 2. The phenomenon responsible for dry soil sucking up moisture above the ground water level.

Seepage

1. The slow movement of water through a soil. 2. The quantity of water which has slowly moved through a porous material, such as soil.

Liquefaction

1. The sudden, large decrease of shearing resistance of a cohesionless soil caused by a collapse of the soil structure, produced by shock or small shear strains, associated with a sudden but temporary increase of pore water pressures. 2. The process of transforming a soil from a solid state to a liquid state, usually as a result of increased pore pressure and reduced shearing resistance. For example, an action in which a soil deposit (e.g., loose sand) loses its shear resistance temporarily and takes on the character of a liquid; such action, for example, may occur during an earthquake.

Bearing wall

A WALL CAPABLE OF SUPPORTING AN IMPOSED LOAD.

Planted column

A column that is not aligned to a lower floor column.

Eccentric column

A column with a cross section that lacks symmetry may suffer torsional buckling (sudden twisting) before, or in combination with, lateral buckling. The presence of the twisting deformations renders both theoretical analyses and practical designs rather complex.

Axial stress

A force with its resultant passing through the centroid of a particular section and being perpendicular to the plane of the section.A force in a direction parallel to the long axis of the structure.

Lintel

A horizontal structural member (such as a beam) over an opening which carries the weight of the wall above it; usually of steel, stone, or wood.

Girt

A horizontal structural member in the framing, 3 of an early timber-framed house, typically supporting the ends of the ceiling joists and acting as the main horizontal support for the floor above; often located about halfway between the groundsill, 2 and the horizontal timber at the top of the wall (the top plate) The term girt often is

Girder

A large or principal beam of steel, reinforced concrete, or timber; used to support concentrated loads at isolated points along its length.

Seismic load

A load on a structure caused by movement of the Earth relative to the structure during an earthquake.

Transverse load

A load, 1 applied perpendicularly to the plane of the longitudinal axis of a structure, such as a wind load.

Admixture

A material other than water, aggregates, lime, or cement, used as an ingredient of concrete or mortar, and added to the batch immediately before or during its mixing; used as a water repellent, as a coloring agent, as a retarder or accelerator (to modify its setting rate), etc.

Shear stress

A measure of how easily a material can be twisted.

Flexural rigidity

A measure of stiffness of a structural member; the product of modulus of elasticity and moment of inertia divided by the length of the member.

Sand

A naturally occurring grainy material made of finely divided rock and mineral particles; the most common ingredient is silica

Rock

A naturally occurring solid mixture of one or more minerals or organic matter

Geodetic engineer

A professional person who determines the shape, contour and measurement of land.

Porosity

A ratio, usually expressed as a percentage, of the volume of voids in a material to the total volume of the material, including the voids. The voids permit gases or liquids to pass through the material.

Floating Foundation

A reinforced concrete slab used to support and distribute the concentrated load from columns in a soil having low bearing capacity; also called a raft foundation or mat foundation.

Tie rods

A rod in tension, used to bind parts of a structure together

Beam

A structural member, usually horizontal, that carries a load that is applied transverse to its length.

Dowels

A tied reinforced concrete column bears on a spread footing. The bearing area of the footing is much greater than the cross-sectional area of the column. The column and footing are constructed of materials having the same specified strength.

Flat slab

A type of concrete floor which has no beam

Retaining wall

A wall that holds back on earth embankment. A wall which resists the lateral pressure of retained earth or other material.

Lime

A white or grayish-white caustic substance, calcium oxide, usually obtained by heating limestone or marble at a high temperature; used chiefly in plasters, mortars, and cements. In the past, in many areas along the seacoast where limestone was scarce, seashells were heated to obtain lime.

pre-stressing force

Act of transferring stress in prestressing tendons from jacks or pretensioning bed to concrete member. Transfer Length—Length over which prestressing force is transferred to concrete by bond in pretensioned mem bers.

Working stress

Actual stress due to load applied. Determined by the effect of the max size and most favorable position of any strength-reducing characteristics permitted in the grade

Inert Materials

Also called aggregate

Plasticizer

An admixture for making a concrete or mortar mix workable with little water.

Truss

An assembly of structural members joined to form a rigid framework, usually connected to form triangles..

Column

An upright structural member acting primarily in compression.

Essential facilities

Aviation control towers fall to what type of occupancy

crippling load

British term for buckling load.

Reinforced concrete

Concrete into which steel reinforcing bars have been embedded to impart tensile strength to the construction.

Slab

Considered a compression member (n) a large, thick, flat piece of stone, concrete, metal,or wood. / 평판

Post Tensioning

Done on site. Wires are put in loosely, concrete poured in, then wires are tensioned after 28 days

Tensile force

Force applied in opposite directions to stretch an object PULLED APART

Brittleness

Hard and likely to break or crack

Temperature reinforcement

In reinforced concrete, reinforcement that is designed to resist tensile stresses resulting from changes in temperature.

Allowable stress

In the design of structures, the maximum unit stress permitted under working loads by codes and specifications

Soft storey

Is a storey whose lateral stiffness is less than 70% of the stiffness of the storey above

Weak storey

Is a storey whose strength is less than 80% of the strength of the storey

Bearing wall system

It is a structural system without complete vertical local carrying space frame

Shear wall

It is designed to resist lateral forces parallel to the plane of the wall

Bottom bars

Longitudinal bars serving as tension reinforcement in the section of a concrete beam subject to positive moment

Curing

Maintaining the humidity and temperature of freshly placed concrete during some definite period following placing, casting, or finishing to assure satisfactory hydration of the cementitious materials and proper hardening of the concrete.

Elastic limit

Maximum stress that a material will withstand without permanent deformation.

Precast concrete

Method of building construction where the concrete building member is poured and set according to specification in a controlled environment and is then shipped to the construction site for use.

1/20

Minimum thickness of one-way slab when it is simply supported

effective depth

Of a beam or slab section, the depth measured from the compression face to the centroid of the tensile reinforcement

Moment of inertia

Of a body around an axis, the sum of the products obtained by multiplying each element of mass by the square of its distance from the axis

Proportional limit

Point at which the deformation is no longer directly proportional to the applied force. Hooke's Law no longer applies.

Parapet wall

Projection of the exterior wall or façade of a building wall is the part of any wall entirely above the roof line.

Boulders

Rock fragments that are bigger than 2 feet in diameter

One way slab

Slab supported on two sides and bending takes place predominantly in one direction only

Floating

Smoothing newly applied mortar, plaster, or concrete with a trowel or float.

Bundled bars

Sometimes employed consisting of two to four bars tied in direct contact with each other to serve or act as one unit reinforcement place at the corner of lateral ties

flexural strength

That property of a solid which is an indication of its ability to withstand bending.

Elasticity

The ability of a material to bounce back after being disturbed

Pavement

The durable surfacing of a road, sidewalk, or other outdoor area

Impact load

The effect of a moving load upon a stationary structure. Dynamic and sudden load placed on a rope, typically during a fall.

Jacking force

The force exerted temporarily by the device which introduces tension in tendons in prestressed concrete.

Footing

The lowest, widest part of the foundation that distributes the load over a broad area of the soil.

Section modulus

The moment of inertia of the area of the cross section of a structural member divided by the distance from the center of gravity to the farthest point of the section; a measure of the flexural strength of the beam.

Inflection point

The point on the length of a structural member subjected to flexure at which the direction of curvature changes and at which the bending moment is zero

Crippling

The sharp bending or buckling when a column is loaded heavily is called _____.

Torsional stress

The shear stress on a transverse cross section which results from the action of a twist.

Tensile stress

The stress per square unit area of the original cross section of a material which resists its elongation.

Live load

The weight of movable objects such as people, furnishings, machines, vehicles, and goods in or on a building.

Dead load

The weight of the building or building components.

Two way slab

__ work best for bays that are square or nearly square , are reinforced equally in both directions and share the bending forces equally between the two directions

Tendons

a reinforcing strand in prestressed concrete. In prestressed concrete, a steel element such as a wire, cable, bar, rod, or strand used to impart prestress to the concrete when the element is placed under tension.

Deck

a structure of planks or plates, approximately horizontal, extending across a ship or boat at any of various levels, especially one of those at the highest level and open to the weather

Soils engineer

an engineer specializing in the analysis of soils and soil load-bearing capacity, and in determining adequate footing and foundation requirements for a structure.

Flexural stress

bending caused by a combination of tension and compression

Materials engineer

focus in developing new and better materials; concerned with processing of materials

Braced frame

frame with diagonal bracing, resists lateral thrust and gravity load

Pier

in architecture, is an upright support for a structure or superstructure such as an arch or bridge. Sections of structural walls between openings (bays) can function as piers.

Boundary element

is an element at the edges or openings or at perimeters of shear walls or diaphragms.

Prestressed concrete

is structural concrete in which internal stresses have been introduced to reduce potential tensile stresses in concrete resulting fro loads. Wires are put into tension within a form and then concrete is poured in, released after 28 days. This practice induces camber which gives greater strength

Adhesion stress

is the tendency of dissimilar particles or surfaces to cling to one another (cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another). The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are certain emergent mechanical effects that will also be discussed at the end of the article.

Fatigue

is the weakening of a material caused by repeatedly applied loads. It is the progressive and localized structural damage that occurs when a material is subjected to cyclic loading. The nominal maximum stress values that cause such damage may be much less than the strength of the material typically quoted as the ultimate tensile stress limit, or the yield stress limit.

Hazardous facilities

occupancies and structures housing or supporting toxic or explosive chemicals or substances; Non- building structures storing, supporting or containing quantities of toxic or explosive substances.

Yield point

point at which deformation becomes permanent. The lowest stress in a material (less than the maximum attainable stress) at which the material begins to exhibit plastic properties; beyond this point an increase in strain occurs without an increase in stress.

Temperature bars

rebars placed perpendicular to load supporting bars to prevent cracking due to temperature changes

Aggregates

sand, gravel, crushed stone, or recycled concrete that are put into composite materials such as concrete and asphalt concrete. Adds strength to the overall composite material.

Gravel

small bits of hard rock use as aggregate in construction or for ornamental purposes in gardens and fish tanks.

Rupture

sudden breaking or bursting of a structure or organ

Circumferential stress

tension caused by transmurial pressure + wall thicknes Pr / h

Bond stress

the adhesive for per unit area of contact between reinforcing bar and the surrounding concrete developed at any section of a flexural member

Fracture

the cracking or breaking of a hard object or material.

Shear

the parallel force that shifts a structure in two opposite directions

Permeability

the state or quality of a material or membrane that causes it to allow liquids or gases to pass through it.

Pre-tensioning

type of prestressing, concrete is poured around stretched steel members