Ch 3 Flashcards
What are the most critical aspects of engineering design for a building
Type and magnitude of forces
What is the force acting on the inside of a structure called
Stress
What is the support system that resists loads called
Reaction
Equilibrium exists when
Support a load equal or greater to applied load
When does total collapse happen
Loss of equilibrium
What is a common reaction of a horizontal component
Bending
What is the most common load on a structure
Gravity
What are the common sources of vibration on a structure
N
B
E
What causes structural members to expand and contract
Temp
What changes the direction of force within a structure
Shrinkage
What is classified as the direction of force within a material
Stresses
What pulls material apart
Tension
What squeezes material together
Compression
What slides material past adjacent plane
Shear
What loads causes unique stresses on external alignments
A L
T L
E L
What load is in a fixed location
Dead
What load is not in a fixed location
Live
What load is applied steadily or gradually
Static
What loads involves motion
Dynamic
What load produces localized forces
Concentrated
What type of load is water
Live
What kind of pressure is applied by winds
Direct
What is the primary consideration when designing buildings to with stain wind
Direct pressure
What locations can walls be insufficiently braced
Construction
Demo
Fire buildings
What is the most complicated load that must be accounted for
Seismic forces
What is the typical life span of a building
50 yrs
What are the most significant forces of an earthquake
Horizontal movement
Lateral loads
What increases the flexibility of a connection
Expansion joist
What isolates buildings from horizontal movements
Base isolation
What bracing is effective against ground motions
S W
C B
What type of load does soil exert
Lateral
What pressure is soil against the foundation
Active
What pressure is the foundation against the soil
Passive
What structural member carries a perpendicular load
Beam
What beam is free to rotate
Simple support
What type of beam resist bending
Cantilever
What beam commonly supports balconies
Cantilever
What flange carries comprehensive stress
Top
What flange carries tensile stress
Bottom
What is the centerline of the web known as
Neutral axis
What structural member supports axial load
Column
How do tall, thin columns fail
Buckle
How do short columns fail
Crushing
What force do arches produce
Inclined
What are arches most often used for
Roofs
Entrance to masonry buildings
What buildings are arches most often used in
Masonry
Cables are usually made of
Steel
What structural member are made of triangles
Trusses
What are the top and bottom members of a struss called
Chords
What is the typical distance of a truss span
22-70ft
Modern trusses may exceed how many feet
100
What are bar joists used for
Roof and floors in fire resistant construction
What are 3 dimensional truss structures
Space frames
What type of load do space frames support
uniform loads
Where are load bearing walls commonly placed
Exterior of a structure
How far are steel studs placed apart
12-16 inches
What type of construction carries transverse loads
Post and beam
What size post supports roofs
6x8
What type of system allows bending stress through joints
Rigid
What are shell structures commonly constructed of
Concrete
What type of structure is a shell
3D
What prevents arches from spreading
Horizontally Tie Rods
What is the middle section of a truss called
Web
Diagonal
What carries most of load resisting the bending
Top and bottom flange
What can change the direction of forces between structural elements
Temp
What creates stresses in the top of a beam
Compression
What creates stresses in the bottom of a beam
Tension
What is stress is created in the cross section of a beam
Shear stress
What load creates uniform stresses across the cross section
Axial
What load does not pass through the center of the cross section
Eccentric
What load creates a twisting effect that creates shear stress in a material
Torsional
What are considered part of the dead load
Structural elements
What load is not precisely quantifiable
Live
What loads may cause structural failure
Dynamic
What load creates a non uniform load
Concentrated
What does wind flowing around the object produce
Drag
What does wind produce by suction effect
Negative pressure
What are effective against long slow vibrations
Shear walls
Corner bracing
What is a less common system of building isolation
Sliding system
What occurs when sandy soil near water sources is loose
Soil liquefaction
What are the stresses in a cable
Tension
What is the life span of membrane structure for building codes
180 or more days
What is the life span of a membrane structure for fire codes
Less than 180 days
What stresses do arches produce
Compressive interior
What does a stream of 250 gpm produce
2080 lbs water per min
What is the static load of 3 inches of water
21 lbs per sq ft
What the 3 types of accommodations for seismic loads
Base isolation
Expansion joints
Dampening mechanisms
What absorbs resonant energy
Dampening mechanisms
What are the 3 directional movements of seismic loads
Lateral
Torsional
Resonant
What stresses are primarily created in a column
Compressive
What forces do concentrated loads produce
Localized
What loads do concentrated loads produce
Non uniform
What are arches designed with for minor adjustments
Hinges
What do steel stud walls have for stability
Diagonal bracing
What roof do rigid frames have
Gable
