Chap 3 Flashcards
structural design
Direction of forces from loads acting on interior of structural members is expressed as ?
Stress
Forces within structural supports systems that resist applied loads are referred to as
reaction R
Any effect that a structure must be designed to resist like gravity, wind , earthquakes ..
load
any interaction that may change the motion of an object
force
condition of balance that exists when a structural system is capable of supporting the applied load
EQUILBRUIM p. 66
A REACTION W/IN a structural component that opposes a vertical load
bending Moment
Most common load imposed on a structure ?
gravity
Sources of vibration can include
Natural ( wind) , building related ( vent system ) external ( traffic )
what changes external to building may cause peripheral structural members to expand and contract
Temperature pg.67
Pulls material apart referred to as tensile stress
Tension
squeeze the material is referred to as
compression streee
slides one plane of material past an adjacent plane
shear
what forces often can be visually identified and evaluated
external forces
what forces must be calculated
Interior forces p. 68
load applied to CENTER of cross section of a member and perpendicular to that cross section
axial load
loads perpendicular to the cross section of the structural members , But which does not pass THROUGHT THE CENTER of the cross section
eccentric loads
loads applied OFF CENTER from the cross section of the structural compentent
Torsional load
Point at which materials causes to perform
failure point
Ratio of failure points of materials to maximum design stress `
factor point p. 69
Load types can meet multiple categories that are based on factors such as ?
Change over time
load application velocity
weight distribution
a load that is fixed in its location
dead load
loads that is not fixed or permanent
Live load
loads that are steady or applied gradually
static load p. 70
loads that involve motion ( wind, falling )
dynamic loads
For dynamic loads to stop moving, the surface it impacts must
absorb the kinetic energy
Dynamic loads may cause ?
structural failure
Rain and snow are
Live loads
ponding is
water accumulation. 72
Energy possessed by moving objects because of motion
kinetic
air pressure less than that of the surrounding atmosphere
negative pressure
water at a depth go 3 inches adds a static load of
21 pounds per sq ft.
Straight line winds apply forces to a surface is ?
direct pressure
wind flowing around the objects may catch what ?
drag