Structural Flashcards
Dead loads
Live loads:
Other loads
Dead loads: Buildings weight, fixed partitions, fixed service equipment
Live loads: people and loads do to occupancy. movable office partitions.
Does NOT include snow, wind, or other environmental loads..
does NOT include construction loads, earthquake loads, flood loads
Other loads
Occupancy category:
Occupancy category:
1: Agg buildings, storage buildings, temp buildings
2: All other buildings….most stuff
3-1. Schools (except very small)
3-2. Healthcare
3-3. Jails
3-4. 300+ covered
4-1. Essential service buildings 4-2. Emergency Shelters 4-3. Hospitals with ER or surgury 4-4: Power generation 4-5: Water for fire pressie
Uniform live load examples
Residential (single & multi living areas)
Public areas (lobby, restaurants, gyms)
Corridors and exits:
Balconies and decks:
Uniform live load examples
Residential (single & multi living areas)
40psf
Public areas (assembly, lobby, restaurants, gyms): 100psf
Corridors and exits: 100psf
Balconies and decks: 1.5 live load of area served (100 max)
Handrail/ guardrail loads:
Grab bars:
Handrail/ guardrail loads:
Linear load: 50 psf
concentrated load: 200 pounds
Grab bars: 250 pounds any direction any location
Roof Loads:
is rooftop landscaping dead or live load?
What is the live load for diff roof gardens
Roof Loads:
Landscaped roof are dead load. based on weight of planters and totally saturated soil
unoccupied roof garden has dead load of planters plus 20 psf live loads. occuppied roof gardens have dead load of planters/soils etc plus 100 psf live load
Snow load:
How to determine snow design load?
What other option do you have for snow design loads for ROOFS?
Factors that impact snow load?
Snow load:
snow design loads: CBC chapter 16 says to see ASCE chapter 7 (American Society of Civil Engineers)
You can use the snow ground loads found in CBC chapter 16 because instead of going to ASCE because the roof should always have less snow on it than the ground due to wind/heat/ etc
snow load factors:
- slope of room
- warm or cool roof. warm has less snow
- wind exposure can blow snow off
- rain on snow surcharge
- snow drifts on roofs against wall or higher structure
- Snow sliding from upper roof to lower roof.
- rough/ smoothness of roof
Wind loads:
How to determine wind load?
What direction is wind assumed to come from?
What if structure is shielded by another structure?
Wind loads:
CBC refs ASCE
- any/ all horizontal direction.
- does not matter, shielding does not reduce wind load design
walls/ partitions over 6’ tall must resist how much horizontal force?
What type of load is this under in the CBC?
- as much as need but no less than 5 psf
- Live load…opening doors etc I guess
Wind loads:
“open building”
“low rise building”
Wind loads:
Open building: 80% open walls
low rise building (for wind load): height is less than smallest width and is 60’ or under
What is “Basic Wind Speed”
Typical CA wind speeds
3 second gust at 33’ above grade in wind category C
used to be 85mph now 110 mph ?
Soil later loads:
what bld components need to resist soil later loads?
What forces must these components resist?
What code lays out these requirements?
What is a main variable in the soil later load in the design chart?
Rough range of loads seen?
Soil later loads:
-Basements, foundations, retaining walls
- overturning
- sliding
- water uplift
- foundation pressure
- CBC
- unified soil classification
- 30 to 100 pound per sf per foot of dept
Wind load:
Wind surface roughness categories?
Wind exposure categories?
Wind load:
surface roughness category:
B:Urban and suburban areas, wooded areas or other terrain with numerous closely spaced obstructions having the size of single-family dwellings or larger.
C: Open terrain with scattered obstructions having heights generally less than 30 feet (9144 mm). This category includes flat open country, and grasslands
D: Flat, unobstructed areas and water surfaces. This category includes smooth mud flats, salt flats and unbroken ice.
Exposure category:
B: = < 30’ mean bld height, B surface roughness for 1500’ min. upwind
> 30’ mean bld height, B surface 2500’ min. or 20x bld height upwind (which ever is greater
C: all others
D:
-D surface roughness 5000’ min. upwind
- B or C surface roughness but site is within 600’ of a D roughness area.
Rain load:
how much water must a roof be able to hold structurally
Rain load:
-Up to the overflow drain heights
Earthquake loads:
Seismic Design Category. What is used to determine this?
Seismic Design Category: what are they and generically what types of buildings fall under each type
Earthquake loads:
- Occupancy Category / Risk Category
I-IV - Site Class
(based on soil from geo)
A-F - Mapped acceleration parameters
AKA type of bld + type of soil + seismic activity in area
standard seismic categories (A-D)
A: good soil / little ground shaking
B: I,II, III class blds with moderate shaking
C: I,II, III class blds with MORE SEVERE shaking -IV buildings with MODERATE SHAKING
D: SEVERE SHAKING not near major fault line.
——–special ones——-
E. I, II, II near major major fault
F. IV near major fault
category 1,2,3: A: little shake good soil B: moderate shake C: significant shake D: Sever shake E: near major Fault
Category 4 A: little shake good soil C: moderate shake D: significant shake D: Sever shake F: Near major Fault
Earthquake loads:
What is a Site Class?
Where is it found?
What is it used for?
What are the different site classes?
Earthquake loads:
Site class is type of soil
geotec
structural uses it combined with rick category and seismic activity to come up with the buildings Seismic Design Category
A: Hard rock B: Rock C: very dense soil with rocks D: stiff soil (standard default) E: soil with lots of clay F: high qualification
