Slide 1In This Unit…Slide 3Slide 4Slide 5Slide 6Compressive and tensile stresses in building componentsTensile and compressive stresses in a suspension bridgeSlide 9Modes of transfer of solar heat through a brick cavity wallThermal Resistance (R-value)Thermal ResistanceInsulating MaterialsSlide 14Questions about InsulationInsulation in floor over crawl spaceInsulating materialsSlide 18Unfaced fiberglassFaced fiberglassGranular InsulationBoards: perlite & expanded polystyreneInsulating concrete formworkPlacing insulating concreteSlide 25Lecture 3: Properties of MaterialsKamalesh Panthi, Ph.D.Department of Construction ManagementEast Carolina UniversityCMGT 2210 - Construction & Civil MaterialsIn This Unit…Properties of MaterialsStructural PropertiesThermal PropertiesAir and Water Vapor Flow PropertiesFire Related PropertiesAcoustical PropertiesLoad Resistance – The Structural Properties of MaterialsSmall spans in stonebrittle material, weak in tensionDiscovery of arch made longer spans in stone possibleStresses in a cableCompressive and tensile stresses in building componentsTensile and compressive stresses in a suspension bridgeThermal Properties of MaterialsModes of transfer of solar heat through a brick cavity wallThermal Resistance (R-value)How well a material resists heat flow depends on:Thickness of Material (L)Type of MaterialWhen L increases R increases, i.e., R LBut R also depends on material type, i.e. their resistivity, Therefore, Thermal Resistance (R)= LThermal Resistance•A material with a high R-value resists the flow of heat, and is called a thermal insulator.•A material with a low R-value allows heat to flow through it easily, and is called a thermal conductor.Insulating MaterialsCalculating R-Value R = L (thermal resistance X thickness)If the value of concrete is 0.15, what is the R-value of a 6 inch concrete wall?R = (0.15)(6) = .9 If the value of fiberglass insulation is 3.5, what is the R-value of 6 inch thick blanket of fiberglass insulation?R = (3.5)(6) = 21Questions about Insulation•Where to insulate?•Building envelope•How much insulation to use?•Varies with•Climate (heating degree days, cooling degree days)•Economics (return on investment)•Energy codeInsulation in floor over crawl spaceInsulating materials Fibrous Granular FoamedFibrous Insulation - thermal resistivity due to air contained between fibers Types Mineral fiber derived from glass (fiberglass) natural rock (rock wool) slag (slag wool) Cellulose derived from recycled newspaper, wood and sugarcane Forms Batts Blankets Semi-rigid boardsUnfaced fiberglassFaced fiberglassGranular Insulation Expanded perlite (glassy volcanic rock) Expanded vermiculite (mica) Expanded polystyrene (combustible polymer)Boards: perlite & expanded polystyreneInsulating concrete formworkPlacing insulating concreteFoamed insulation: Foamed in
View Full Document