LS Construction Flashcards
Construction/Contract Doc’s Components
- Bid Documents
- Contract (b/w owner. & contractor)
- Drawings
- Specifications
- Bond forms
- General & Special Conditions
ASTM
American society for testing & materials
Compacting fill for subgrade
Remove organic matter
Compact in 6-12” lifts/layers
Dressed lumber
Described by # of sides dressed: S4S, S2S (surface 2 sides)
About 1/2” less than name ie 2x4 is 1.5x3.5
AWPB
American wood preservers bureau
Set standards for pressure treated wood
3 Classes of wood preservative treatments
- water borne (paintable)
- oil borne (paintable)
- creosote (not paintable)
Timber retaining walls
- 1st timber below surface
- stagger joints
- toe nail timber together w/ 6, 10, 12” spikes or drill 1” hole 12” away from end & drive 1/2” galv pipes or 3/4” reinforcing rods thru all timbers to ground
- batter walls over 3’ ht: 1” per 1’ of height
- anchors & deadmen: every 10-15’ lf & 3-4’ vertical ht
Concrete
- Mixture of water, Portland cement, and fine & coarse aggregate
- water & Portland cement combine & harden binding aggregates: hydration
- 1 Portland cement sack = 1cf = 94 lbs
- 1 cy of cement should contain 5 sacks
Coarse aggregate (cement)
1/4” - 1.5”
For patios, drives, walks etc aggregate should not exceed 1/3 of its thickness
5 types of Portland cement
Type I: general purpose/residential
Type II: moderately sulfate resistant walkways, pilings, bridges
Type III: high early strength; reaches most strength within 1st week of curing. Rush jobs/winter/forms
Type IV: slow curing. Water dams
Type V: sulfate resistant for alkaline soils or in ground water. Gains strength slowly.
Low water-cement ratio
Less water more cement the stronger & more durable
Compressive strength in concrete
- increases with age
- is tested after 28 days of curing
- NC state code minimum is 2500 psi
Slump test
- 12” truncated cone: 8” @ base & 4” @ top
- Fill cone with concrete
- pull cone off & set next to concrete cone
- measure how much concrete has sagged
For drives, walks, slabs:
Hand method: max slump of 5” & min of 2”
Power methods: max slump of 3”
Air-entrained concrete
Cement with minute air bubbles that allow for water to expand into when freezing
Forming concrete
- have 90 min after mixing to pour & strike off
- moisten forms & subgrade before pouring
- consolidate poured concrete in form
- strike it off level with a screed
- 2nd screed pass to smooth it
Pouring concrete slab
- work from corners into center
- place loads up against pervious
- after strike off, work w/ bull float or Darby
- once bleed water has left & concrete stiffened slightly
Concrete control joints
- depth of 1/4 the thickness of pour
- slabs: max 10’ apart
- walks: max 5’ apart
- after scoring float surface w/wooden float
Concrete curing
- when over 70 degrees keep continuously wet for 5 days
- when between 50-70 degrees keep wet for 7 days
Expansion joint
- 1/4-1/2” wide
- extend full width & depth of slab
- premolded asphalt impregnated fiber
- recess filler 1/4-1/2” from top of surface
How many bricks in a linear foot of soldier course?
6 bricks in 1 lf of soldier course
How many bricks in a linear foot of sailor course?
3 bricks in 1 lf of sailor course
When should tree wrappings be installed & removed?
Install in the fall to protect from sun scald & remove in the spring.
For what reasons should you stake or guy trees?
- Protection
- Support
- Anchorage
When should stakes & guys be removed?
After one growing season.
How deep should screenings/sand at walks be?
1” - 4” deep
What should a driveway base be composed of?
- min. 4” compacted aggregate base
- 1” of screenings
Water Borne Treated
- CCA (chromated copper arsenate)
- ACA (ammoniacal copper arsenate)
What is the typ. ht of a riser & depth of a tread on deck steps?
Typ. Riser: 7.5”
Typ. Tread: 11.5”
At what height above ground are rails needed?
30” above ground
