STRUCTURES Flashcards
WHAT ARE, AND WHAT KIND OF 4 STATIC LOADS ARE THERE?
APPLIED SLOWLY TO A STRUCTURE AND REACHES A PEEK WITHOUT FLUCTUATING GREATLY.
- DEAD LOADS
- LIFE LOADS
- FOUNDATION LOADS
- IMPACT OR KINETIC LOADS
4 FAILING CONDITIONS OF SEISMIC LOADS?
- SOFT AND WEAK STORIES
- DISCONTINUOUS SHEAR WALLS
- VARIATIONS IN PERIMETER STRENGTH
- REENTRANT CORNER
3 STRESS TYPES TO EXTERNAL FORCE?
- TENSION
- COMPRESSION
- SHEAR
HOOK’S LAW, structures STRESS FORMULA
F = P / A
STRESS = TOTAL FORCE APPLIED / TOTAL AREA
FORCES WITHIN A BUILDING IN A SEISMIC EVENT - FORMULA
FORCES WITHIN A BUILDING IN A SEISMIC EVENT OR EQUAL TO THE WEIGHT OF THE BUILDING.
F = M*A
FORCE (F) = THE MASS (M) OF THE BUILDING x THE HORIZONTAL ACCELERATION (A)
3 structure types FOR SEISMIC RESTRAINT
- MOMENT RESISTING FRAME
- BRACED FRAME
- SHEAR WALLS
10 SEISMIC MITIGATION strategies
- -CONTINUOUS LOAD PATH
- -LOW HEIGHT TO BASE RATIO
- -EQUAL FLOOR HEIGHT
- -SYMMETRICAL PLAN
- -MINIMIZES TORSION
- -UNIFORM SECTION
- -SEISMIC RESISTING ELEMENTS AT PERIMETER
- -SHORT SPANS
- -NO CANTILEVERS
- -NO OPENINGS IN DIAPHRAGMS
3 FUNDAMENTAL PRINCIPLES OF EQUILIBRIUM APPLIED BUILDINGS.
- The sum of all vertical forces acting on a body must equal zero
- The sum of all horizontal forces acting on the body must equal zero
- The sum of all moments acting on the body must equal zero.
Allowable max BEAM STRESS - FORMULA
F = M / S
ALLOWABLE BENDING STRESS = MAX.MOMENT / SECTION MODULUS
MOMENT FORMULA FOR CENTER POINT LOAD
M = P*L / 4
MOMENT = POINTLOAD*LENGTH / 4
MOMENT FORMULA FOR UNIFORM LOAD
M = W*L^2 / 8
MOMENT = UNIFORM LOAD * LENGTH SQUARED / 8
WHAT AFFECTS THE BENDING MOMENT? what not?
LOAD, TYPE OF SUPPORTS & LENGTH AFFECT MOMENT,
Not: MATERIAL AND CROSS-SECTION
SHEAR FORCE FORMULA FOR POINT LOAD
V = W / 2
COLUMN SLENDERNESS RATIO
SLENDERNESS RATIO = L / R
L=Length
R = RADIUS OF GYRATION
SPAN STEEL GIRDERS IN FT
10-70
SPAN Flat wood trusses IN FT
40-150
SPAN Pitched wood trusses IN FT
40-100
SPAN Deep Long span joists IN FT
90-144
SPAN Glued lam beams IN FT
10-60
SPAN FLAT STEEL TRUSSES IN FT
40-300
SPAN PRESTRESSED SINGLE T IN FT
20-120
SPAN Prestress. conc girders IN FT
40-120
SPAN Conc arches IN FT
40-320
SPAN Suspended cables IN FT
450
SPAN Geodesic dome IN FT
400