MATERIALS OF CONSTRUCTION - AYBU

CE 244MATERIALS OF CONSTRUCTION

Course Objectives To develop a basic understanding of keymaterial properties, requirements, and relatedbehavior characteristics of typical constructionmaterials.

Course Content TypesProduction methodsUses in constructionProperties and related tests of the followingmaterials of construction: Building StonesMetalsClay ProductsGypsumLime CementsMineral AggregatesConcreteTimber

Course Content These materials are used in all civilengineering structures such as; buildings,bridges, highways, railways, tunnels, dams,harbor structures, towers & etc.

CLASSIFICATION OF CIVILENGINEERING MATERIALS1.According to their phases2.According to their internal structure &chemical composition

Phase Classification1. Gases : Air, oxygen, CO22. Liquids : Water, chemical admixtures3. Semi-solids : Fresh pastes, mortars, asphalt4. Solids : Metals, hardened concrete

Internal Structure & ChemicalComposition Classification1. Metals : (formed by metallic bonds)A. Ferrous (iron, cast iron, steel)B. Non-ferrous (aluminum, copper, zinc, lead)2. Polymers : (long chains having moleculesof C, H, O, N which are formed bycovalent bonding. The chains are bound toeachother either by covalent bonds or Vander Waal’s forces.)A. Natural (rubber, asphalt, resins, wood)B. Artificial (plastics)

Internal Structure & ChemicalComposition Classification3. Ceramics : (mainly aluminosilicates formedby mixed bonding, covalent and ionic)A. Structural clay products (bricks, tiles, pipes)B. Porcelains4. Composite Materials :A. Natural (agglemerates)B. Artificial (Portland cement, concrete)

Internal Structure & ChemicalComposition Classification5. Reinforced Composite Materials :(reinforced concrete, reinforced plastics) One of the most important task of anengineer is to select the most suitablematerial for a given civil engineeringstructure.

Factors Determining the Choiceof Proper Material for a Structure Strength, rigidity & Durability Requirements–––– Permanent loading Creep StrengthRepeated loading Fatique StrengthImpact loading Toughness & ResilienceSurface loading Hardness & Resistance to abrasionEnvironmental Requirements– Temperature change coefficient of thermal conductivity– Moisture movement permeability– Chemical effects chemical composition

Factors Determining the Choiceof Proper Material for a Structure Economy. Choose the cheaper & availablematerials considering– Initial cost– Useful life– Frequency of maintenance– Cost of maintenance– Salvage value– Comfortability

Example: Comparison of concretepavement vs. asphalt pavement foreconomy.ConcreteAsphaltInitial Cost– Useful Life –Frequency of Repair –Cost of Repair– Salvage Value Comfortability–

General Properties of CivilEngineering Materials Physical **Mechanical **ChemicalOther– Thermal, Acoustical, Optical, Electrical** Most CE Applications Focus on Physical& Mechanical Properties

Physical Properties Properties of physical structure––––densityspecific gravityporositypermeability– surface energy– texture (micro, macro)– other (color, thermalexpansion, shape)

Mechanical Properties Resistance to applied loads (stress)initially & over time– stiffness– strength– fracture / yielding(brittle / e (bending)torsiondirect shearmultiaxial

Chemical Properties Chemical composition, potentialreaction with environment– oxide content– carbonate content– acidity, alkalinity– resistance to corrosion

Determining the Propertiesof Civil Engineering Materials Properties of materials are determined by Laboratory testing Field testing. To avoid inconsistencies in test resultsSTANDARDS are devised which describethe test apparatus and the procedure.

Items that are usuallystandardized in a test are: Obtaining test specimens and number of specimensSize and shape of the specimenPreparation of specimens for testingTemperature & moisture during preparation &testingType of machineryRate of loadingInterpretation of test resultsWriting a report

Standardization InstitutesTurkey - Turkish Standards Institute (TSE) England - British Standards Institute (BSI) Germany - Deutsche Institute Norm (DIN) U.S. - American Society for Testing andMaterials (ASTM) Europe - European Committee forStandardization (CEN)

CEMENTITIOUS MATERIALS Although there are several differentmaterials which have adhesive properties,three types are of particular interest to civilengineers.Glues : materials of gelatinous naturederived from vegetable or animal sources.Bituminous Materials : complex hydrocarbonVarious Compounds of Calcium : gypsum,lime, cements

CEMENTITIOUS MATERIALS Cementitious materials are substanceswhich, upon certain chemical reactionsattain binding properties Non-hydraulic cements (gypsum and lime) Hydraulic cements (portland cement) Hydraulicity is that property of gainingbinding value when mixed with water andremaining stable when exposed to water.

SPECIAL PROPERTIES OFCEMENTITIOUS MATERIALS Fineness : Particle size.Normal Consistency : A standard amount of waterwhich gives a certain fluidity to the paste.Time of Setting : Beginning of complete loss ofplasticity.Sand Carrying Capacity : Amount of sand that canbe added without harming plasticityHardening : Formation of solid phase; completeloss of plasticity.Yield : Volume of final product obtained incomparison with volumes of constituent materials.

of C, H, O, N which are formed by covalent bonding. The chains are bound to eachother either by covalent bonds or Van der Waal’s forces.) A. Natural (rubber, asphalt, resins, wood) B. Artificial (plastics) 3. Ceramics : (mainly aluminosilicates formed by mixed bonding, covalent and ionic) A. Structural clay products (bricks, tiles, pipes) B. Porcelains 4. Composite Materials : A. Natural .