Transcript Engineering Concepts Chapter 1 Terms

Engineering Concepts
Chapter 4 Terms
ABUTMENT
The part of a structure
that directly receives thrust
or pressure.
ARCH BRIDGE

A bridge that uses long
span arches for
support.
BEAM BRIDGE

A bridge whose main
structural element
consists of a beam set
across two or more
vertical supporting
members.
BUCKLE

Failure caused by
bending, giving way, or
crumpling due to
excessive force.
BRITTLE

The description for a
material which is
neither ductile nor
malleable and will fail
suddenly without
warning.
COMPRESSION

The effect of a force
which tends to shorten
an object in the
direction of the force.
For example, the
towers of a suspension
bridge are in
compression.
DEAD LOAD

A permanent part of a
structure. A dead load
does not change over
time.
DENSITY

Mass per unit volume.
DYNAMIC LOAD

A quick exertion of
force such as an
explosion, collision,
etc.
ELASTIC DEFORMATION RANGE

A range during material
testing where if the
load is released the
material will return to
its initial size and
shape.
FIXTURE

Apparatus used in
manufacturing
processes to assemble
large pieces of material
in a consistent fashion.
FREE-BODY DIAGRAM

TAB
TAC
TAD
TAE
A sketch of an object
(body) of interest with
all the surrounding
objects stripped away
and all of the forces
acting on the object
(body) shown.
JIG

Apparatus used in
manufacturing
processes to assemble
or measure pieces of
material in a consistent
fashion, smaller than a
fixture and can be
moved.
LIVE LOAD

A load moving across
or within a structure.
MOMENT OF INERTIA

MOI
.
An indication of the
stiffness of a particular
shape. The higher the
moment of inertia, the
less the deflection.
NEWTON’S FIRST LAW

(The Law of Inertia) –
Objects at rest tend to
stay at rest, and objects
in motion tend to stay
in motion at a constant
speed in a straight line
unless acted upon by
an unbalanced force.
NEWTON’S SECOND LAW

The net force acting on
an object in a given
direction is equal to the
mass of the object
multiplied by the
acceleration of the
object in the same
direction as the net
force.
NEWTON’S THIRD LAW

The force of one object
(object 1) acting on
another object (object
2) is equal in
magnitude and
opposite in direction to
the force of the second
object acting upon the
first.
PLASTIC DEFORMATION RANGE

A range during material
testing where the
material will not return
to its initial size and
shape.
REACTIONS
y

8N
x
c
40o
70o
a
Ra = 4N
70o
b
Rb = 4N
Reactions are passive
forces that are induced
at the supports of a
structure.
STATICS

The study of objects in
a state of equilibrium.
STATIC LOAD

A load that
accumulates over time.
STRESS-STRAIN CURVE

A graph of stress (on
the y-axis) versus strain
(on the x-axis) for
materials under stress;
enables engineers to
learn about the strength
of material as it
deforms elastically and
plastically.
SUSPENSION BRIDGE

A bridge having a road
or deck hung from a
pair of steel cables,
each carried by two
towers, one at each
bank; e.g., the Golden
Gate Bridge over San
Francisco Bay.
TENSION

A situation in which
force is applied to an
object that stretches,
expands or lengthens
the object.
TENSILE

Of or relating to
tension; a “tensile”
force is a force that
serves to stretch,
expand, or lengthen an
object.
TRUSS

A large structural
member that consists of
many smaller parts,
typically in a repeating
pattern of geometric
shapes.
YIELD