TECHNOLOGY

• early 20th century (Germany)
• diamond
• shapes

• dead load
• live load
• rain/snow load
• wind load
• earth and water horizontal loads

- light framed foundations must reach through the unstable organic soil to the stable undisturbed soil beneath the local frost line

- large scale heavy bldg foundations- rock or soil stable enough for massive loads

• soil= any earth material that is particulate
• - boulder- an individual particle of soil too large to lift by hand (or req. 2 hands)
• - cobble- takes a whole hand to lift
• coarse grained soils
• - gravel- particle that can be lifted easily between thumb & forefinger
• - sand- individual soil particles can be seen but are too small to be picked up individually
• fine grained soils
• - silt- roughly spherical, smaller~equidimensional granules
• -clay-  plate-shaped, smaller than silt

continuous mineral material

• - the migration through the soil must be managed
• - dry locations: not under water pressure- spray on asphalt or equivalent
• - wet locations: under water pressure- drainage mat- drain away from building

• - penetration tests- pin/tube hammered into the ground (capacity indicated by # blows of a std driving hammer to advance a tube into the soil by a fixed amt)
• - boring tests- shallow by hand- deep by drilling rig
• - test pits- dig a big hole and see what you find (useful when fdtn is not expected to extend deeper than roughly 16 ft)

• - water table- the depth that the soil is fully saturated & the pressure of the groundwater is atmospheric
• - hydrostatic pressure- pressure exerted by water as it moves through the soil

• - liquefaction- sands & silts w/ high water content are susceptible to this=> a temporary change from solid to liquid state during cyclic shaking (can lead to loss of support for a building foundation or excessive pressure on fdtn walls)
• - liquid limit- the water content at which soil passes from a plastic state to a liquid state
• - plastic limit- the water content at which soil loses its plasticity & begins to behave as a solid
• - testing can determine-- water content of soil, its permeability to water, its shrinkage when dried, its shear & compressive strengths, the amt by which the soil can be expected to consolidate under the load, the rate at which consolidation will take place

• - simple concrete footings
• - column footings
• - wall footing/strip footing
• - concrete slab on grade (1/2 story bldgs, climates with little to no ground frost)
• - floating= bldg weighs approximately the same as the soil excavated for the substructure (stress in soil beneath bldg remains =)
• - continuous spread footings- extend below all organic matter & the local frost line to support the foundation walls

• - caisson (drilled pier)- extends through strata of unsatisfactory soil beneath the substructure of a building until it reaches a more suitable stratum (often contain bells)
• - socketed caisson- drilled into rock at the bottom rather than belled (bearing capacity comes from its end bearing, but also from frictional forces between the sides of the caisson & the rock)
• - piles- differ from caissons in that they are forcibly driven into the earth rather than drilled & poured (may be used where noncohesive soils, subsurface water conditions, or excessive depth of bearing strata make caissons impractical)
•     - end bearing pile= driven until hits firm resistance from a bearing stratum such as rock, dense sands, etc.
•     - friction pile= w/o encountering- may still develop a considerable load- carrying capacity through frictional resistance- work best in silty, clayey, & sandy soils
• - pile caps- join 2-25 piles each, distributes the load of the column or wall
• - grade beams- think of them as reinforced concrete bridges that are spanning between
• the deep foundation points & supporting the walls above

• used where strong earthquakes are common
• - bldgs sometimes placed on base isolators (which flex or yield to absorb much of the ground movement) 
• - frequently used= a multilayered sandwich of rubber & steel plates
• - the foundation & columns are separated by rubber bearings

• - benchmark: never changing reference point used as a base for all elevations
• - elevation: vertical distance between a standard reference point (benchmark) & other point
• - transits 
• - rough layout

• ??
• fdtn walls- formwork- 2 walls strong enough to support concrete weight
• bracing- openings to provide the utilities to the basement

used with whalers frequently

- anchor the building to the foundation

• keeping the cold & heat out 
• insulation at some point in/on the foundation

• - foundation sill plate- usually made of preservative-treated wood for added resistance to insects & moisture
•     - bolted to fdtn as a base for the wood framing
• - sill sealer- made of compressible or resilient material, should be inserted between the sill & fdtn to reduce air infiltration through the gap (some materials also discourage moisture wicking up from fdtn into wood framing)

making round concrete columns with them

• - most common design: cantilevered retaining wall
• - stone, masonry, preservative-treated wood, coast/galvanized steel, precast concrete, or most commonly, sitecast concrete
• - failure may occur through fracture of the wall, overturning of the wall (due to soil failure), lateral sliding of the wall, or undermining of the wall by flowing groundwater
• -most common cause of failure: improper control of drainage

• - the process of strengthening & stabilizing the foundations of an existing building
• 3 alternatives when fdtn capacity needs to be increased:
• 1. the fdtns may be enlarged
• 2. new, deep fdtns can be inserted under shallow ones to carry the load to a deeper, stronger stratum of soil (new piles, caissons to the sides of existing)
• 3. the soil itself can be strengthened by grouting or by chemical treatment

how wood was joined in construction for centuries

• - better structural performance & fire safety (than balloon framing)
• - foundation, floor frame, keep working way up in a series of flat platforms
• - when the fdtn is complete, basement beams are placed, sills are bolted to the fdtn, & the first floor joists & subfloor are installed
• - very detailed nailing schedule 
• - primary components & terms to understand

• remember what nominal size actually means
• - nominal size: what are they called vs. what size they really are (2x4 is very close to 1.5"x 3.5")

• - Foundation
• - Sill- resistant to rot sometimes
• - Rim joist or header joist
• - floor joists
• - blocking
• - sub floor sheathing
• - stud wall
• - rafters if sloped, joists if flat
• - ridge rafters
• - fascia boards
• - outlook rafters
• - ceiling joists

• Roof sheathing
• Wall sheathing: with either plywood or OSB, which provide permanent, very stiff bracing, or with let-in bracing
•     sheathing panels made from wood or paper fiber are intended principally as thermal insulation & to provide a base for water-resistant bldg paper or house wrap (non-structural=> rely on let-in diagonal bracing or strategically located structural panels for lateral force resistance)

• - wind bracing
• - braced wall panels

• - most important factor in keeping floors from squeaking is properly fastening the subfloor to the joists
• - increasing floor stiffness & reducing squeaking- adhesive may be used in conj. with mechanical fasteners
• - deformed shank nails or screws hold subflooring more securely than common nails & contribute to squeak prevention

• - stringer- primary structural component of stairs (2x4s spanning between them & supporting the tread material)
• - riser- nailed with galvanized finish nails to the stringers & clear coated along with the floor boards
• tread
• 

• - an angled notch in the rafter that allows the rafter to seat securely on the top plate of the wall
• - a typical detail at the bearing point of a sloped rafter on a wall
• - toe nailed (or screwed) through the rafter

• what are they in general terms
• - load-bearing high-insulating structural sandwich of OSB (Oriented Strand Board) skins and EPS foam (Expanded Polystrene foam)
• - the sandwich principle creates a structure where the loads are carried by the OSB & spread over the entire surface of the wall on both sides (walls replace dimension lumber framing)
• - typically foam thickness matches dimensional lumber sizes (foam cores available from 1" to 12")
• - run horiz/vertically up to 24'
• - good thermal & moisture advantages, stud loss is minimized
• 

• - Most SIP manufacturers provide panels in both 2x4 and 2x6 varieties, however, bear in mind that those sizes predicate that the 2x4 or 2x6 is sandwiched between the panels.
• - Therefore, your wall thickness to rough structural frame will be 4-1/2" and 6-1/2" respectively. Including the OSB skin is very important to the structure.

• - tape is placed over the SIP joints, especially at roof ridges, to prevent air leakage & water condensation
• - applied directly to the SIPs

• medullary rings: or pith rays- creates paths for the sap perpendicular to the annual rings
• annual rings or growth rings: created by the changes in the speed of growth as the seasons change
• sapwood: the part of the tree where sap still flows
• heartwood: the older, harder, darker part of the tree where sap no longer flows

• softwoods: coniferous (evergreen)
• typical softwood grain= pine, wider grains
• hardwoods: broadleaf (deciduous), not always harder than softwoods (ex. douglas fir is a softwood & balsa is a hardwood)
• typical grain=walnut, tighter grains, more dense

- Forest Stewardship Council: driven in part by the failure of an intergovernmental process to agree on a global forest compact, & the compelling question- what is sustainable forestry?

• seasoned wood: wood can be dried to any desired moisture content, but framing lumber is seasoned when its m. content =/< 19%
• green lumber: when the lumber is freshly cut, unseasoned= much weaker & less stable compared to seasoned lumber

= plain sawn?: dividing the log to produce the max. yield of useful pieces & therefore the greatest economy

• - a process that forces chemical preservatives into the wood to resist rot & insects
• (chromated Copper arsenate, alkaline copper quat (ACQ), micronized cooper quat, etc.)

- plies (layers) run perpendicular to each other so the panel is of = (or close to =) strength in both directions

• which are structural
• Plywood
• OSB - Oriented Strand Board
• Particle Board
• Fiberboard

large beams- made up of dimension lumber - glued together- & quite often left exposed (b/c of rate they burn)

• - for moderate size beams (3.5"- 5" wide) by various depths
• - not typically left exposed

• - laminated veneer lumber: often used for smaller beams 1.75" wide by varying depths.
• - stronger & stiffer than dimension lumber, can be ganged to do the work of heavy paralams
• - made up of thin wood veneers (like plywood) & oriented vertically

• what are advantages of these over dimension lumber
• - PSL- stronger & stiffer than DL
• - basically I beam made out of wood

• = a thin non-structural layer of finish quality wood applied to plywood or other surfaces
• 3 typical ways to create-
• 1. Rotary veneer (toilet paper)
• 2. crown cut- wide ranged
• 3. quarter cut

• 3 types of matching
• 1. book matching
• 2. random matching
• 3. slip matching

• what is the shank of the nail & why is it important
• - tries to hold into place while still drying
• - why the heads are smaller
• face nail, end nail, toe nail

• - screws, lags & bolts, washers & nuts
• - nailing plates
• - joist hangers: used where the ends of joists butt into supporting headers (as around stair openings & at changes of joist direction for projecting bays). provide pockets for the end of the joist & punched holes into which many special short nails are driven in to connect safely
• post caps
• post base
• beam hanger

• - solid wood or gluelam structures where the lumber is left exposed
• - pit dwellings:
• - cruck frame: crucks= primary structural members, usually curved- that transfer loads to the ground but also to each other to create an arch-like meeting
• - braced frames:
• - bents: prefabricated structural frames that include columns, beams brace (lifted into place)

• how is it typically connected? mortise & tenon or steel connections
• - steel connectors
• - mortise, tenon, & dowels

- vertical wood structural members

• +: non combustible, lighter weight, longer spans, consistently sized members, more stable in humid conditions, termite resistant, less drilling for services, 100% recyclable
• -: not yet the std practice for all uses, more labor intensive, thermal conductivity, condensation, insulation costs, higher fastener costs, galvanic action, not a renewable resource (though recyclable)
• structural framing members...
• basic components:
• - self tapping screws
• - C-shaped structural members

what are the agreed upon advantages & disadvantages

• - self tapping screws (drills its own hole, then treads into the hole)
• - c- shaped structural members of various depth, width, & gauge (thickness of the walls) of steel
• - u-shaped runner channels that they slide into- create equivalent of plates & rim boards or rafters
• end clips, web stiffeners, foundation clips, bracing, hangers, channel,

how are the walls braced

one of the big advantages

• yield strength: when the steel deforms in compression
• vs. tensile strength: when does the steel fail in tension
• A36 carbon steel most common
• hot rolled: (not as dense or heavy, much more likely to rust), mill finish- factory finish
• cold rolled steel: (more expensive)

• knowing pictures
• W-shapes- most commonly used for columns & beams
• I-beams & H-beams & their difference

• ordered by ID (inside dimension)
• bar channel (small channel)
• structural channel (big channel)

= & unequal legs

textured for slip prevention

• need to have techniques to provide lateral force resistance
• taller bldgs= rigid core/rigid perimeter design
• diagonal- braced triangular configurations, can rely exclusively on shear connections between beams & columns
• moment: rely on moment connections between beams & columns that are resistant to rotation & therby capable of stabilizing the frame against lateral forces
• shear: stiff walls made of steel, concrete, or reinforced concrete masonrya properly sheathed wall can act like this to resist lateral forces. interior & exterior walls can be shear walls, must be provided in both east-west & north-south orientations & must be distributed more or less symmetrically in the floor plan. Stresses w/in shear walls are proportional to their length, with shorter walls being subjected to higher stresses than those that are longer

• rivets: a single piece of steel deformed to create a connection
• hot steel rivet inserted through holes in the 2 members to be joined, head placed in cup shaped depression of a heavy, hand held hammer, pneumatic hammer drives a set repeatedly against the body to form  2nd head
• bolts:
• welding:  
•     stick welding- solid stick consumable electrode protected by flux that emit CO2 & protects the weld (cheap, messy, requires skill)
•     MIG welding- (Metal Inert gas) consumable wire electrode on a spool & a shield gas constantly fed through the welding gun (more $, less mess, less skill needed)
•    TIG welding- (Tungsten Inert Gas) non-combustible tungsten creates the arc & filler material is added by hand. Used for very fine welding & welding of stainless steel, aluminum, copper... (more expense & skill, almost no mess, good with many materials)

• columns: transfer all the loads vertically, eventually to the foundation
• girders: support the beams (which are the pt loads on the girders) & transfer the loads to the columns
• beams: support the joists & transfer the loads to the girders or columns
• joists (hierarchy): members that support the floor system (considered a distribtd load)

• support the floor/roof loads by transferring the loads to the beams
• bearing seat, web, bottom, & top chord
• 

• placed on steel decking, can span different distances between beams depending on:
• 1. gauge of steel decking
• 2. depth of the steel decking
• 3. reinforcing used in the slab
• 4. the depth of the concrete

coating steel with a thin layer of Zinc, which can be left exposed or painted

• in a plant... dip into acid bath to clean of impurities, dip into a molten bath of zinc at around 860 deg F
• use a plasma cutter to vent (which use compressed air & heated electrically charged gas to cut through the steel)

• pigment: color
• fillers: carry the color
• binders: bind the fillers & pigment together into the material being painted
• primer: bonds to the surface
• finish paints: protects from abuse, sun, etc

+ charged polymer or epoxy sprayed on grounded object which is then heated & cooled to melt & harden the coating

• the patina of the steel
• rusting carbon steel- letting the steel form a patina: rust- works well in an arid climate
• the rust protects the steel but does not rust so much as to weaken the steel

• often known by the trademark COR-TEN
• alloys create a rust like patina that protects the steel & can be used in more demanding climates
• controls rust against failure

open steel grids

masonry adhesive

• - lintels (header)
• - jambs
• - sills

20-25% is the most efficient rise of the span

what is the most important

• - unreinforced or reinforced
• - mono-structure or composite
• - solid walls or cavity walls (wythe, course)

• what is it?
• external & internal

inside, exterior or interior of wall

what is it made of

• load bearing
• - infill technique
• - importance of keeping moisture out (base condition)

• - a form of earth retention in which corrosion-resistant wire baskets are filled with cobble- or boulder-sized rocks & then stacked to form retaining walls, slope protection, & similar structures
• 

surface divider joints- abutment joints, control, & expansion joints

• - volume change joints
• - settlement joints
• - seismic separation joints

• not concrete, a part of it
• concrete: composite material composed of coarse granular material (the aggregate or filler) embedded in a hard matrix of material (the cement or binder) that fills the space among the aggregate particles and glues them together
• fly ash: byproduct of coal-burning power plants, a cementitious binder to lower amt of needed cement

• - solidifies in a moist condition,hydration- bonds elements together when mixed w water
• ~28 days

• determined by the proportioning of the elements in the mix (amt water)
• 200psi-20,000psi

• cone- measures slump/settlement
• conc. is stronger in compression but weak in tension

• rebar: bars of carbon steel with deformations (ridges) to create a frictional bond between the bars themselves & the concrete
• concrete & rebar expand & contract at similar rates

= weakened planes between hardened concrete and fresh concrete

use a concrete vibrator &/or rubber mallets to remove air pockets & large bubbles from the form at the visible....????

- screed


- bull float


- trowels

smooth troweled vs. broom finishes

rounds off the exposed edge of the slab so it won't be chipped as easily

• separate the sections (complete expansion)
•  slab covered with plastic- to keep from curing to quickly (avoiding evaporation)

what they mean

• units
• - how is it typically joined- can be welded together

• cables are cast into the concrete bldg components
• the dead load of the concrete will lead to sagging over time
• cable are pre-tensioned to create a slight upward camber that will level out with loading

- cast-in-place concrete that is then lifted into position

• for a typical 8" slab this is done when the 3,000 psi concrete reaches about 2,000 psi (3-10 days depending)
• you cannot later cut holes through the floor w/o having dependable documents of the reinforcing location or having an x-ray done of the floor (cutting cables would undermine the structure)

• anchoring plates are set at the edges of the slab
• high strength steel strands (tendons) are run in steel or plastic ducts

• 1: beams span one direction
• 2: span in both dir to transfer load to gridded columns, usually done w/o beams unless in a particularly heavy loaded construction

forms & their temporary structure

2 way f.p. (cast-in-place) = most efficient

• shape of structural bay
• span of the structure
• loads
• what finishes & appearance is acceptable
• shear loads
• sound transmission

how does the formwork impact the finish of concrete

• insulated concrete form
• insulated styrofoam, concrete is poured between

Do you want to leave the structure exposed while achieving high fire ratings?

Wood Timbers or Concrete

Can you afford to have the project set up with an extensive sprinkler system?

Are structural components indoor or outdoor? (fire ratings)

• Minimize OFF site time
• - site cast concrete
• - light gauge steel framing
• - wood platform frame
• - masonry 
• - ICFs

• Minimize ON site time
• - steel frame
• - precast concrete
• - heavy timber frame
• - SIP's

• 1-3 story bldgs
• steel frame
• heavy timber frame
• platform frame
• SIPs
• ICFs
• CMUs
• Straw, Adobe
• Load Bearing Masonry walls

• 4-20 story bldgs
• precast concrete
• steel frame
• site cast concrete
• CMUs

• Over 20 stories
• Steel Frame
• Cast in Place Concrete

• - have to design to support future loads whether adding onto above or horizontally
• is fdtn condition not as stable as desired?
• - steel frame with bolted connections
• - heavy timber frame
• - wood platform framing

• -more= more time= increases the cost
• - specialists?

• determine local code: IBC or UBC or...
• IBC is the most common now
• determine use group, then find floor area & height limitations

• getting started-know
• 1. use group
• 2. building types allowed for each use group
• 3. floor area & height limitations for building types

• setbacks= areas to leave for yard
• easements= where you have utilities (power lines above, electric below, sewers, etc.)
•  view restrictions