PSAD

Question 1

energy stored in a material due to its deformation.

Answer 1

Strain energy

Question 2

it indicates the maximum amount of strain-energy the material can absorb just
before it fractures (ability to absorb energy in plastic range).

Answer 2

Modulus of toughness:

Question 3

represents the largest amount of internal strain energy per unit volume the
material can absorb without causing any permanent damage to the material (ability to absorb
energy in the elastic range).

Answer 3

Modulus of Resilience:

Question 4

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

Answer 4

Elasticity:

Question 5

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

Answer 5

Ductility:

Question 6

or ability to resist a deformation within the linear range.

Answer 6

Stiffness:

Question 7

material’s resistance to fracture.

Answer 7

Toughness:

Question 8

material’s resistance to indentation.

Answer 8

Hardness:

Question 9

Any material that can be subjected to large strains before it fractures

Answer 9

Ductile Materials:

Question 10

Materials that exhibit little or no yielding before failure

Answer 10

Brittle Materials:

Question 11

has the same physical and mechanical properties throughout its volume or
material has the same composition at any point.

Answer 11

Homogeneous material:

Question 12

has same physical and mechanical properties in all directions.

Answer 12

Isotropic material:

Question 13

has material properties at a particular point, which differ along three mutually-
orthogonal axes.

Answer 13

Orthotropic material:

Question 14

all cross sections are the same throughout its length.

Answer 14

Prismatic:

Question 15

When a material has to support a load for a very long period of time, it may continue to deform
until a sudden fracture occurs or its usefulness is impaired.

Answer 15

Creep:

Question 16

When a material is subjected to repeated cycles of stress or strain, it causes its structure to break
down, ultimately leading to fracture.

Answer 16

Fatigue:

Question 17

lateral deflection that occurs when long slender members are subjected to an axial compressive
force.

Answer 17

Buckling:

Question 18

A slight increase in stress above the elastic limit will result in a breakdown of the material and
causes it to deform permanently.

Answer 18

Yielding:

Question 19

When yielding has ended, an increase in load can be supported by the specimen, until
it reaches a maximum stress referred to as the ultimate stress.

Answer 19

Strain Hardening:

Question 20

Just after the ultimate stress, the cross-sectional area will begin to decrease in a localized region
of the specimen, until the specimen breaks at the fracture stress.

Answer 20

Necking:

Question 21

It is the space between two adjacent floors

Answer 21

Story:

Question 22

rigid horizontal planes used to transfer lateral forces to vertical resisting elements.

Answer 22

Diaphragms:

Question 23

wall designed to resist lateral forces acting in its own plane, typically wind and seismic loads.
- stiffened walls and are capable of transferring lateral forces from floors and roofs to the
foundation.

Answer 23

Shear wall:

Question 24

is the point where the object “suffers” no torque by the effect of the gravitational force
acted upon it.

Answer 24

Center of gravity:

Question 25

center of resistance of a floor or diaphragm against lateral forces - It is the point through which the resultant of the resistance to the applied lateral force acts.

Answer 25

Center of rigidity:

Question 26

point through which the resultant of the masses of a system acts. - It is the point through which the applied lateral force acts.

Answer 26

Center of mass:

Question 27

The point through which the resultant of the restoring forces of a system acts.

Answer 27

Center of stiffness:

Question 28

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

Answer 28

Eccentricity:

Question 29

It is the total design lateral force at the base of a structure.

Answer 29

Design seismic base shear:

Question 30

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

Answer 30

Story drift:

Question 31

is the lateral displacement of the story relative to the base

Answer 31

Story displacement:

Question 32

Discontinuities in a lateral force path

Answer 32

Out-of-plane offsets:

Question 33

occurs when the structure’s center of mass does not coincide with its center of rigidity

Answer 33

Torsional shear stress:

Question 34

It occurs when a building period coincides with the earthquake period.

Answer 34

Resonance:

Question 35

time period of undamped free vibration of a structure.

Answer 35

Natural period:

Question 36

rate at which natural vibration is absorbed. - The effect of internal friction, imperfect elasticity of material, slipping, sliding, etc in reducing the amplitude of vibration

Answer 36

Damping:

Question 37

The geographical point on the surface of earth vertically above the focus of the earthquake.

Answer 37

Epicenter:

Question 38

The originating earthquake source of the elastic waves inside the earth which cause shaking of ground due to earthquake.

Answer 38

Focus:

Question 39

the capacity to undergo large inelastic deformations without significant loss of strength or stiffness.

Answer 39

Ductility:

Question 40

is a state in saturated cohesionless soil wherein the effective shear strength is reduced to negligible value. - condition when soil tends to behave like a fluid mass.

Answer 40

Liquefaction:

Question 41

a measure of the strength of shaking during the earthquake

Answer 41

Intensity:

Question 42

a measure of energy released in an earthquake.

Answer 42

Magnitude:

Question 43

are instruments used to record the motion of the ground during an earthquake.

Answer 43

Seismographs:

Question 44

It is one in which the lateral stiffness is less than 70 percent of that in the storey above or less than 80 percent of the average lateral stiffness of the three storeys above.

Answer 44

Soft Storey:

Question 45

It is one in which the storey lateral strength is less than 80 percent of that in the storey above.

Answer 45

Weak Storey:

Question 46

Inverse of stiffness.

Answer 46

Flexbility

Question 47

The deformation that occurs in yielding.

Answer 47

Plastic Deformation