PSAD terms

soft storey

A building which has a floor which is less than 70% as stiff as the floor immediately above it, or less than 80% as stiff as the average stiffness of the three floors above it.

shear center

A lateral load acting on a beam will produce bending without twisting only if it acts through this point on the beam section.

In the formula Vn=Vc+Vs, Vs is the:

nominal shear strength provided by shear reinforcement

cantilever beam

A beam built into a rigid support at one end, with the other end being free.

d

The critical section for shear in no-prestressed beam is located at a distance ____ from face of support.

stiffness

The resistance to deformation of a member or structure measured by the ratio of the applied force to the corresponding displacement.

shrinkage

Decrease in either length or volume of a material resulting from changes in moisture content or chemical changes.

Saint-Venant's Principle

This principle states that the maximum stress diminishes rapidly as we move away from the point of load application. At a distance from the end of the bar equal to the width of the bar, the stress distribution is nearly uniform, and the maximum stress is only a few percent larger than the average stress.

0.75

For tension-controlled section, the reduction factor for shear is:

ground displacement

Which of the following can be measured by a seismometer?

inverse of stiffness

Which of the following refers to the flexibility of a structural system?

torque

The component of the resultant couple that tends to twist the bar.

Rapture stress

The stress of the material at failure is called:

creep

When a material is loaded over a long period, it causes it to deform continuously until fracture.

fatigue

Fracture caused when a material is subjected to repeated cycles of stress or strain.

Vu≤ϕ(Vc+0.67f′c−−√bwd)

In one-way shear strength, which of the following criterion is correct?

elasticity

The property of a material by virtue of which a body returns to its original, shape after removal of the load is called:

Saint-Venant's Principle

This principle states that the maximum stress diminishes rapidly as we move away from the point of load application. At a distance from the end of the bar equal to the width of the bar, the stress distribution is nearly uniform, and the maximum stress is only a few percent larger than the average stress.

T/2

A shaft of diameter D is subjected to a twisting moment of T and bending moment of M respectively. If the maximum bending stress is equal to the maximum shear stress developed, the M is equal to:

pre-tensioning

Stressing high strength steel before concrete hardens.

axial force

The force component that is perpendicular to the cross section, tending to elongate or shorten the bar.

shear wall

A structural system composed of braced panels to counter the effects of lateral load acting on a structure. Wind and seismic loads are the most common loads that these are designed to carry.

stiffness

This refers to the ability of the structure to resist changes in shape.

storey drift

Refers to the lateral displacement of one level relative to the level above or below.

bending moment = product of stress and section modulus

Which of the following statements is correct?

zero

At the neutral axis of a beam cross-section, the flexural stress is:

torsional shear stress

What will develop if the center of mass and center of rigidity of a structure does not coincide?

beam

This refers to a slender bar that carries transverse loading; that is, the applied force are perpendicular to the bar.

elasticity

Refers to the property of a material which makes it return to its original dimensions when load is removed.

resonance

It occurs when the structure's period coincides with the earthquake period.

plastic centriod

The point in a column cross-section where the resultant force acts when all the steel has yielded in compression and the entire concrete section is subjected to its maximum compressive stress.

net pressure

Pressure on soil due to column loads transmitted to the footing.

flexibility

The inverse of stiffness.

torsionally sensitive

Buildings with small eccentricity or if the maximum lateral displacement found in an equivalent static analysis in any level of a building exceeds 1.4 times the average displacement of the two ends of the level being considered, the building is considered:

fatigue

A fracture phenomenon resulting from a fluctuating stress cycle.

inversely proportional

Bending stress is _________ to the section modulus.

m^4

Which of the following gives a unit of moment of inertia.

center of mass

The point on a structure where the resultant vertical force acts.

drift index

The ratio of lateral deflection to the height of the building.

storey drift

Refers to the lateral displacement of one level relative to the other level above or below.

strain hardening

Phenomenon wherein ductile steel, after undergoing considerable deformation at or just above yield point, exhibits the capacity to resist substantially higher loading than that which caused initial yielding.

Stressing high strength steel after the concrete has been cast and has attained sufficient strength.

post-tensioning

The ability of the material to absorb energy in the plastic range.

toughness

pre-tensioning

Stressing high strength steel before concrete hardens.

extreme fiber

The maximum bending stress in an I-beam occurs at

0.85

Factor β for 17MPa≤f′c≤28 is:

residual stess

The stress that remains in an unloaded member after it has been formed into a finished product. (Examples of such stresses include, but are not limited to, those induced by cold bending, cooling after rolling, or welding.)

center of rigidity

It is the point through which the resultant of the resistance to the applied lateral force acts.

0.65

For compression-controlled section, the reduction factor for bending is:

toughness

The ability of the material to deform in plastic range without breaking.

ground displacement

Which of the following can be measured by a seismometer?

moment diagram, shear diagram

The shear is the slope of the_______The load is the slope of the_______

elastic limit

The maximum stress a material can withstand before the permanent deformation. It is the material's highest limit before the material's plastic deformation can occur. Once the stress or force is removed from the material, the material comes back to its original shape.

inverse of stiffness

Which of the following refers to the flexibility of a structural system?

elastic limit

The greatest stress that can be applied to an elastic body without causing permanent deformation.

toughness

Measurement of the ability to absorb energy without fracture.

ductility

The capacity of a structure to undergo large inelastic deformation without significant loss of strength or stiffeners.

post-tensiong

Stressing high strength steel after the concrete has been cast and has attained sufficient strength.

shear

The force components lying in the plane of the cross section, tending to slide the parts of the bar lying on either side of the cross section relative to one another.

eccentricity

The distance between the center of mass and center of rigidity.

Yield point

The point in the stress-strain curve where a material will undergo an appreciable elongation or yielding without corresponding increase in load.

distance from the extreme compression fiber to the centroid of longitudinal tension reinforcement

The effective depth of a beam is defined as the:

fs≤fy

A concrete member is compression controlled if: Where fs is the stress in extreme tension steel.

strain hardening

This occurs when a metal is strained beyond the yield point. An increasing stress is required to produce additional plastic deformation and the metal apparently becomes stronger and more difficult to deform.

the strain in extreme tension steel is greater than or equal to 0.005

A reinforced concrete member is tension controlled if:

creep

The increased strain or deformation of a structural element under a constant load.

bending moment

The component of the resultant couple that tend to bend the bar.

torsional shear stress

Occurs when the structure's center of mass does not coincide with its center of rigidity.

moment resistance/permissible bending stress

Section modulus of a beam is calculated as:

0.90

For tension-controlled section, the reduction factor for bending is:

h/2

In the case of a triangular section, the shear stress is maximum at the:

soft storey

A structural irregularity in which the storey shear strength is less than 90% of that in the storey above.

neutral axis of the section

An inverted T-Beam T-Section is subjected to a shear force F. The maximum shear stress will occur at:

At the bottom of the section

A cantilever beam of T cross-section carries a uniformly distributed loas. Where does the maximum magnitude of bending stress occur?

creep

Loss of stress that takes place with the passage of time as concrete is held at constant strain.

toughness

The ability of the material to deform in plastic range without breaking.

yielding

A material condition that causes it to deform permanently even due to slight increase of stress.

creep

Loss of stress that takes place with the passage of time as concrete is held at constant strain.

maximum

At the neutral axis of a beam cross-section, the shearing stress is:

shear wall

A structural system composed of braced panels to counter the effects of lateral load acting on a structure. Wind and seismic loads are the most common loads that these are designed to carry.

shear center

A lateral load acting on a beam will produce bending without twisting only if it acts through this point on the beam section.

Yield point

The first stress in a material at which an increase in strain occurs without an increase in stress, the yield point less than the maximum attainable stress.

drift

Lateral deflection of a building.

square section beam will be stronger

Two beams of equal cross-sectional area are subjected to equal bending moment. If one beam has a square cross-section and the other has a circular cross-section, then:

Ultimate stress

The maximum ordinate of the stress-strain diagram is called:

yielding

The stress point where a material will have appreciable deform when small amount of stress is experienced.

Modulus of Rigidity (G)

Resistance to shear deformation

Modulus of Rupture (Fr)

Resistance to bending before it breaks

Poisson's Ratio (v)

For elastic deformation, the negative ratio of lateral and axial strains that result from an applied axial stress.

Point of zero moment and point wheere the sag of the beam transitions. 0 deflection

Point of Inflection

Concrete

Which of the following compromiuses the bulk volume of concrete (CE NOV 2019)

Slump Test

This test determines the consistency of concrete

Water-to-cement ratio

The most important factor in concrete mix

Kinetic Friction

What do you call the retarding force acting opposite a body in motion

Resultant

What do you call the force which determines whether the body will be in equilibrium or will have a varying state of motion

Bearing stress

The compressive pressure between two bodies that are pressed against each other is called:

Shear stress

Stress caused by forces acting parallel to a cross-section, attempting to slide adjacent layers past each other.

Axial stress

Stress caused by forces acting along a member's longitudinal axis, pulling (tension) or pushing (compression) it directly.

Flexural stress

Stress caused by bending, which produces tension on one side of a structural member and compression on the other.

Strain

Deformation per unit length is called: