STRUCTURAL TERMS

Bridge Cap

"is the highest part of a bridge pier, on which the bridge bearings or rollers are seated. It may be of stone, brick or plain or reinforced concrete, usually the last for heavy loads."

Joist

beam directly supporting a floor

Live Load

load which may be removed or replaced on a structure. Moving loads or movable loads

girder

A horizontal beam that supports other beams; a very large beam, especially one that is built up from other sections.

Aggregates

gravel, sand, slag, crushed rock or similar inert materials which form a large part of concretes,asphalts or roads including macadam.

Diaphragm

a structural system used to transfer/transmit lateral forces like wind and earthquake load to the vertical-resisting elements. Horizontal bracing systems

boring

making a hole in rock blasting, using a rotative or percussive drill

1 bore hole

0-50 sqm

2 bore holes

50-500 sqm

3 bore holes

500 sqm or more

Gusset Plate

a flat steel plate used to connect the members of a truss; a stiffener plate

Punching Shear

The failure in a base when a heavily loaded column strikes a hole through it.

Seismograph

A device that records ground movements caused by seismic waves as they move through Earth

Span

The distance between supports for a beam, girder, truss, or other horizontal structural member; to carry a load between supports.

Span

it is the extent of space between two supports of a structure. It also refers to the structure so supported.

Modulus of Elasticity

What do you call ratio Stress/Strain?

Modulus of Elasticity

The ratio of the increment of some specified form of stress to the increment of some specified form of strain, such as Young's modulus, the bulk modulus, or the shear modulus. Also known as coefficient of elasticity, elasticity modulus, elastic modulus.

Modulus of rigidity

Also called the Shear Modulus, it is the ratio of shear stress to the shear strain and is denoted by G.

yield point

it is the first stress in a material at which an increase in strain occurs without an increase in stress

yield point

the stress at which noticeable, suddenly increased deformation occurs under slowly increasing load

elastic limit

Maximum stress that a material will withstand without permanent deformation.

elastic limit

the stress beyond which further load causes permanent set. In most materials it is also the limit of proportionality.

Plastic Limit

The minimum moisture content at which the soil can be rolled into a thread one-eighth of an inch in diameter without crumbling and is determined by trial and error.

deflection

The distance a beam or structure deforms under loading, typically due to bending in a beam. The elastic movement of loaded parts of a structure.

shear

force directed parallel to a surface

shear

force that causes one part of the body to slide relative to an adjacent part in a direction parallel to their plane of contact

Stress

Force per unit area.

strain

Change in the length of an object in some direction per unit.

Grade Beam

the US term for ground beam

Tendon

a pre-stressing bar, cable, rope, strand or wire

slenderness ratio

The ratio of the effective length of a column to its least radius of gyration.

resilience

the strain energy stored in an elastic material per unit of volume

Ductility

The ability to be pulled into thin wires. The ability of a metal to undergo cold plastic deformation without breaking.

Modulus of Rapture

the breaking stress of a cast-iron, wooden or mass concrete rectangular beam, calculated on the assumptions that the tensile strains in the beam are equal distances from the neutral axis

structure

it is an assemblage of framing members designed to support gravity loads and resists lateral forces

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.

Essential Facilities

Structures that are necessary for emergency operations subsequent to a natural disaster.

Special occupancy

Buildings used for college or adult education with a capacity of 500 or more students fall to what type of occupancy?

retaining wall

A wall designed to resist the lateral displacement of soil or other materials.

Diaphragm

It is a horizontal or nearly horizontal system acting to transmit lateral forces to the vertical-resisting elements, including horizontal bracing systems

soft story

A story whose lateral stiffness is less than 70 percent of the stiffness of the story above. Such an abrupt change of stiffness should be avoided if possible.

Weak Story

Is one in which the story strength is less than 80% of that of the story above.

P-delta effect

The secondary effect on shears and moments of frame members induced by the vertical loads acting on the laterally displaced building frame.

girder

Large beam supporting a smaller beam.

Elasticity

Advantage of steel over concrete

crippling

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

Buckling

Usual failure of a long column

yield

What usually happen to reinforcing steel in a reinforced concrete slab or beam if such member is about to collapse?

Bundled bars

Reinforcing bars put in a contact to act as a unit

Every 600mm; 15-25 seconds

Use of concrete vibrator

Seismicity

The degree, to which a location is subjected earthquake risk, usually refers to the frequency to occurrence and magnitude of past earthquake and expectation of future seismic activity.

Columns

Ties are for

Beams

Stirrups are for

Planted Column

What do you call a column that is not aligned to a lower floor column?

Pre-tensioning

Type of pre-stressing for which tension is applied prior to the placing of concrete

Flat Slab

Type of concrete floor which has no supporting beams.

Bond Stress

The force adhesion per unit area of contact between two bonded surfaces.

span length

Distance between two structural supports

Jacking Force

Temporary force exerted by a device that introduce tension into a pre-stressing tendon.

Setting

Rapid hardening element is called "early [blank] cement"

settlement

The gradual movement of an engineering structure due to compression of the soil below the foundation.

Permeability

Ability of rock or soil to allow water to flow through it

Workability

SLUMP TEST IS DONE IN FRESH CONCRETE IN ORDER PRIMARILY TO DETERMINE

Aggregates

Inert materials used in concrete which occupy more than 75% of the volume of the hardened concrete.

Shear wall

The wall that resists horizontal forces applied in a plane of the wall.

Contraction Joint

is a formed, sawed, or tooled groove in a concrete structure to create a weakened plane and regulate the location of cracking resulting from the dimensional change of different parts of the structure.

Development Length

Length of embedded reinforcement required to develop the design strength of reinforcement at a critical section.

Post-tensioning

It is a method of pre-stressing in which tendons are tensioned after concrete has hardened.

kg m/s2

Newton is expressed in

N/m2

Pascal (Pa), the SI unit of stress, is expressed in

Psi

pounds per square inch

Psi

The unit of stress in the Imperial system

strain gauge

An instrument for measuring minute deformation

deflection

A term to describe the magnitude to which a structural element is displaced when subjected to an applied load.

elastic limit

It is the amount of stress that a material can undergo before moving from elastic deformation into plastic deformation

yield point

It is the first stress in a material at which an increase in strain occurs without an increase in stress

rigid

A material that possesses a very high Young's Modulus is

F/A

Stress

dL/L

Strain

Modulus of Elasticity

stress/strain

Poisson's Ratio

Ratio of lateral strain to longitudinal strain.

Proportional Limit

the greatest stress a structure can withstand without permanent deformation

soil compaction

A method of mechanically increasing the density of soil

top

The main bars for cantilevered slabs are located at

End of slab

What is the Best Location of Support for a One Way Slab?

Laitance

It is a flaky layer of hardened but weak hydrated cement and fine aggregates which began as a milky layer on the upper surface of the concrete mass during the curing process which was caused by an excess amount of water used in the mixture or by too much vibration.

Footing

Structure that transfers the load (weight) of the house to the soil, supports the foundation

hydrostatic pressure

It is the depth below ground water level multiplied by the weight of water

pressure

What causes the Upward Force that acts on footings?

Allowable bearing capacity

is the ultimate bearing capacity divided by a factor of safety.

Soil Bearing Pressure

What do you call the Upward Force acting on spread footing?

yield strength

A36 Steel is the most common type of Steel Alloy. What does the number 36 mean?

American Society for Testing and Materials

What is ASTM?

ASTM A6

The ASTM standard specification for General Requirements for Rolled Structural Steel bars, plates, shapes, and sheet piling.

ASTM A36

The ASTM standard specification for Carbon Structural Steel

ASTM A325

The ASTM standard specification for structural bolts, steel, heat treated, 120/105 ksi Minimum Tensile Strength

moment-resisting frame

Is a frame in which members and joints are capable of resisting forces primarily by flexure:

Effective Length of Column

The distance between points of zero moment on a compression member is

Development Length

Length of embedded reinforcement required to develop the design strength of reinforcement at a critical section.

Bearing wall system

a structural system without a complete vertical load-carrying space frame