BUILDING TECHNOLOGY I

Mid-Term Exam Lecture Notes

Disclaimer: These notes are short handed outlines for  review purposes only and are not intended to cover all the material discussed in class.

Lecture Outline #1

Document Formats

Phases of architectural Services

Schematic                     5%

Design Dev.                  15%

Construction Doc.     50%

Bidding/Negot.            10%

Const. Admin.              20%

Sheet Organization

Cover sheet - index, title block

Demolition

Civil

Landscape

Architectural

            Legend , Site Plan,  Floor Plans , Elevations , Sections , Ext. Details , Int Details,             elev., Schedules , Interior Design , Structural,  Mechanical - Plumbing, HVAC, Fire             Prot.,Electrical

General Symbols - Abbrev. Sht.

            Material Designations

Lecture #2    CODES

Zoning Codes- to prevent overbuilding (maintain light and air), overcrowding and maintain similar  functions (no factories in a residential area)

Restrictions to building:

            Use  - Zoning Map - C, R, L - limited Ind.,  G - general Ind.,

                        #’s define degree of resriction, worst case rules

            Height - Max. also set by codes, worst case rules

Site coverage - Floor Area Ratio - F.A.R.  Percentage of site footprint to total floor area allowed           

Example:  Ratio 1 : 2  -  1000 s.f. site , = 2000 s.f. total max.

            Setbacks - from property lines,  maintain privacy and street patterns
   
       Easements - utility and access clearance

Building Codes

Pennsylvania - by locality
Philadelphia - BOCA

Fire Safety Codes

-Use Groups - number of people  &

-Construction Type - 1 thru 5, Fire resistance

            Combustible vs. Noncombustible (Materials) - Protected vs. Unprotected (Sprinklered)

to determine:    Height and Area Restrictions &

                        Fire resistance Ratings of Structural Materials - Hours

                        UL Ratings - pre-rated assemblies

Lecture #3      3 Main Physical Systems

-Structural

-Exterior Envelope

-Interior Dividers

Basic Structural Elements - single or in combination

            LINEAR - Post and Beam - column and beam system, skeletal grid

            PLANAR  - Bearing Wall - load bearing plane

Loads

Static Loads - relatively constant

            -Dead - fixed
   
       -Live - variable 

Dynamic Loads - sudden and changeable

            -Wind - pressure or suction
   
       -Seismic - sudden earth movement

Forces - sum of all forces = 0,  forces want to reach ground by quickest path

            -Uniform load - distributed - slab
         
  -Point load - concentrated - beam

Stresses

            -Tension - pulling apart
   
      -Compression - pushing together

Columns - vertical compressive load

            -Slenderness ratio -capacity varies inversely with length
   
      -Buckling - eccentrically or overloaded

Lecture #4   Spanning Space

Beam - lateral transfer of load, Simple span

            -Bending - inefficient transfer of loads results in both tension,(bottom) and   compression, (top)

             Optimization of beam material - vertical orientation

            Wide flange principle - material moves to outside

-Shear Stress - cutting stress

-Cantilever - stresses reverse

-Moment - stress from the tendency to rotate around an axis

Truss - beam with efficient use of material

Triangulation - gives rigidity, individual members only in T or C, efficient

Arch - linear, form-active element - efficient through its geometry

            shape is close to natural flow of compression  forces around an opening

            Parabola is most efficient

            develops lateral thrust at base

Terms        Springline,        Keystone

Vault - extended arch

Lecture #5    Structures 3

Lateral Stability  - resists wind and seismic, rectangle with ‘pinned joints’ will collapse

-Diagonal Bracing - Triangulation T & C change per direction

-Rigid Frame - corners braced to resist lateral forces

-Shear wall - rigid plane incorporates triangulation in material

Overturning Moment - Greater the base> greater the resistance

Form Active Structures - derived strength from shape,

            curved in 2 directions to self -stabilize

Dome - rotated arch except circumferential T in lower and C in upper portion

Hyperbolic Parabaloid - made from straight lines, saddle shape, concrete

Membrane Structures - All forces in T,

            Fabric, cable nets

            stretched in opposite directions, saddle shape

Pneumatic Structures - Inflated,  supported by air pressure

Lecture #6 GEOGRAPHIC FACTORS

SOILS

2 Main Types

Course Grained - Visible particles

-Gravel         -Sand

Fine Grained - non-visible, grouped by shape

-Silt             -Clay- -plate shaped particles slip under load

Bearing - resistance must equal load

-course grain best bearing with little amount of voids

-rated in PSF

-soil test boring - tests for types, density, water

TOPOGRAPHY - elevation of the land

affects:   -building and foundation form - raised on stilts or cut into hill

-site drainage - maintain natural drainage patterns, flood plains

-micro-climate - elevation, orientation- S vs.N, large bodies of water

Contours -

Contour Map(topographic)

            Field survey - w/ transit         Lines indicate elevation        Spot elevation marks - “connect the dots”

Lecture #7 FOUNDATIONS - part of Substructure that distributes load from Superstructure to ground

Types by Load Distribution

-Pier/Pile - Point load

-Linear/Wall - Linear load

-Slab/Mat - Uniform load

Footings - Distribute load from wall or column to soil, 45 degree angle, Linear vs. Pad             Foot to the Leg

Types by Catagory

DEEP -Pier/Pile  - penetrate past bad soil

-Caissons - single,  drilled cast conc. column bearing on suitable soil or bedrock, Belled  bottom

-Piles - multiple, clustered steel, conc., or wood end bearing or Friction Pile, top cap, act together as a large caisson, driven into earth

Grade Beam - connects piles and caissons,  not  main structural system

SHALLOW -Linear/Wall and Slab/Mat  -  must have good bearing soil

-Wall - Linear footings,

-Pad footings

EXCAVATION - Removal of soil to bear on suitable

-sloped - on large sites, slope varies per soil cohesiveness

-Shoring/Sheeting - constricted sites, usually driven into ground as cantilever against soil

- Cut and Fill - redistribute land on site

Concerns:

Settlement - Wide designed Footing, Steel Rebar placement - footing and wall

Drainage -Hydrostatic pressure -  keep water off wall

-Perforated Tile,

-Gravel backfill - Coarse grained soils

-Damp-proofing - membranes - sheets, liquid asphalts, bentonite clay, sprayed, rolled,                                     Drainage Mesh

Frost -bottom of footing below frostline

-Slab - On Grade, little or no frost,  Mat, thick slab acting as a single footing

Concrete Block and Wood foundations - not recommended except for Crawlspace - water penetration, durability

Lecture #8 WOOD INTRODUCTION

Advantages - strength in T & C for weight, easily assembled, shapeable, beautiful, renewable

Disadvantages - defects, warpage, burns, decays

TREES - Growth

Bark - Protection                                                  Heartwood - dead
   
         Cambium - New cell growth at edge                      Pith - small first growth             
   
         Sapwood - Nurtient route to leaves, major portion   

Cells - Long cells paralell to long axis of trunk = direction

            of grain, Several times stronger with grain

TYPES - Softwoods - Coniferious, Pine, Fir,  Building wood

 -Hardwoods - Maple, Oak, Walnut,  Finish wood

LUMBER - squared wood used for construction

Plainsawn - max. yield, variety of grain patterns, tends to distort,

Quartersawn - even grain pattern (finish wood), more stable, expensive and wasteful

SEASONING - drying lumber to strengthen and resist decay, moisture < 19%

            -air dry in stacks
            -kiln dryed, monitored, faster

DEFECTS -

            -Cupping and Warping,distortion due to shrinkage while drying
            -Checking - cracking against the grain
            -Splitting - cracking with the grain
            -Knots - branch
            -Decay and Insect damage

GRADING - Seperation by appearance and strength, (defects)

Nominal size - size when fisrt cut from tree, common reference

Actual size - size after dressed(planed) and seasoned

-1/4”less            1”  =  3/4”

-1/2” less            2”  =  1 1/2”                  4”  =  3 1/2”

                                                          3”  =  2 1/2”                  6”  =  5 1/2”

-3/4” less            8”  =  7 1/4" +

FASTENERS

NAILS - hammer or Nail Gun - Air powered or .22 cal. charge

-Common - flathead                        -Finish - small head to be hidden

measured in “pennies” represented “d”, 8,10,16 most common

Galvanized - zinc coated, no rust for wet conditions

SCREWS - more secure hold in material, used mainly for hardware, cabinets and drywall

BOLTS - connection where extra strength is needed

TOOTHED PLATE - cheap truss connector

JOIST HANGER - Used to hold side bearing joists

Lecture #9 HEAVY TIMBER

Earliest from of spanning with a beam

Traditional method of building until mid 1800’s - Used in barns, mills

Set on Braced Framing(half timbering) for lateral  or  Masonry walls

Large wood beams and columns

Joined by interlocking wood to wood connections           Nails were expensive

Post and Beam Framing - major members, larger spacing            Decking spans between,  thicker- determined by distance

FIRE RESISTANCE -

Large timbers - grater capacity to absorb heat - slower to catch fire

Forms protective charred outer layer, prevents collapse

Fire-cut - prevents toppling of wall

ENGINEERED LUMBER - WOOD PRODUCTS

Modern day equivalent - large pieces of lumber dwindleing and $

Wood connected by adhesive to create new products

Reuses unusable pieces

Stronger than solid wood - will not break at adhesive

Laminated sheets

Plywood - Veneers - sliced off log

Laminated Beams

Glue Lams - 2x’s
Micro-lams(LVL) - plywood
Strand Beams - Recycled Scrap pieces
Decking - T & G - planks

Lecture #10 WOOD FRAMING

WOOD LIGHT FRAME

-Balloon frame - first method, requires long pieces, firestops

-Platform Framing - creates own platform, shorter pieces, allows tilt-up const., integral firestops

FRAMING DEFINITIONS - from found. up

FOUNDATION CONECTION

Sill - with anchor bolt

Joist - floor support beam, spaced 16” o.c.

Header - closes off end of joists

Subfloor - also creates diaphram action in floor

Sole plate - base of frame wall

WALL & WINDOW

Studs - structural, 16” o.c., double at windows, triple min. at corners

Sheathing - 4’x8’, diagonal bracing

Sill

Header - double with plywood

FLOOR PLATFORM -

Top plate - double 

(similar to found.)

ROOF FRAMING

Birdsmouth

Ceiling Joist - less stress than floor

Rafter - angled joist, Pitch-Rise & Run, 3/12 min.

Fascia

Collar Tie - prevents horizontal thrust

Ridge Board - for connection

Ridge Beam - for support, when don’t want horiz. Tie