Shallow foundations frequently use footings to transfer weight to soil; wall footing defined as the part of the building that rests on the bearing soil and is wider than the foundation
column footing-square pad of concrete that supports a column
Deep Foundations are more costly than shallow; utilize piles and pliers
piles- are driven into the ground and develop their load carrying ability either thru friction with surrounding soil or by being driven into contact with rock
pliers- are constructed by first drilling or digging a shaft and filling it with concrete.
Difference between shoring and underpinning?
Underpinning is permanent
Solid lumber sizes for boards, dimension lumber, and timbers
Boards have a nominal thickness of 2 inches or less
Dimension lumber has thickness of to 2 to 4 inches or more(8 to 18ft)(roof rafters24ft)
Timbers have a nominal thickness of 5 inches or more
Laminated wood members are produced by joing flat strips with glue.
Beams produced like this are called?
Sizes and shapes may also be made(curves)
can be produced from __ to __ inches in depth and up to ___ft in length
3 to 75 inches in depth
100ft in length
What are the 3 types of wood joints?
Butt joint- not used where tensil forces are present
Scarf Joint- scarf and finger are used where tension and tensile are present
wood panels include
plywood-commonly 1/4" to 1 1/8' thich, 4X8 sheet
sandwich or composite panels
Types of nonveneered panels
OSB, particleboard, waferboard
particleboard used for flooring, 8' X 40'
Trusses- light frame- 2inch nominal lumber alighned in a plane usually connected by gusset plates
heavy timber truss- are made up of members up to 8 or 10in thick
wood i-beams- frequently used for floors also rafters
2 main ways to treat wood with fire retardent?
*all treatment decrease strength
Chemicals used in fire retarding
Ammonium Phosphate, Ammonium Sulfate
Boric Acid, Zinc chloride
Main application of thermoplastic composite lumber
Outside decks and railings
maind adv is resistance to weathering
flame spread rating 80
Heavy Timber framing
columns not less than 8X8's and beams not less than 6X10's
Post and Beam framing
columns and beams greater than wood frame yet lesser than heavy timber
posts are usually 4X4 or 6X6 and spaced 4 to 12 feet
Light wood frame
either Ballon Frame or Platform frame
2X4's or 2X8's spaced 12, 16, or 24 inches
Brick Veneer framing
adds little structural support
must be tied at intervals of 16 inches
every 6th course is a header course
Nonreinforced masonry construction is limited to what height?
Floors are required to be 3inch tongue and groove with 1 inch nominal tongue and groove flooring
Roofs are required to be 2 inch tongue and groove or 1 1/8'' structural panel or planks
non-bearing partitions and walls are required to be not less than 2 layers of 1 inch matched boards or laminated construction 4 inches thick or 1 hr FRR