Materials and Method of Construction

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November 28, 2022

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Materials and Method of Construction

(Introduction)

Engineering Materials

There are thousands of materials available to the engineer !
Basic construction materials: concrete, steel, clay products & Wood etc.

Course Objectives
- To develop a basic understanding of key material properties, requirements, and related behavior characteristics of typical construction materials.

Types
Production methods
Uses in construction
- Building Stones
- Metals
- Clay Products
- Lime
- Cements
- Aggregates
- Concrete
- Glass
- Paints and Varnishes
Properties of the following materials of construction:

These materials are used in all civil engineering structures such as;
- buildings
- bridges
- highways
- railways
- tunnels
- dams
- towers etc.

Books

Fundamentals of Building Construction Materials and Methods by Edward Allen and Joseph Iano 5th Edition
Building Materials by S.K Dughal 3rd Edition
Building Construction (Principals, Materials and System) by Madan Mehta 2nd Edtion

CLASSIFICATION OF CIVIL ENGINEERING MATERIALS

According to their phases
According to their internal structure & chemical composition

Phase Classification

Gases : Air, oxygen, CO2
Liquids : Water, chemical admixtures
Semi-solids : Fresh pastes, mortars, asphalt
Solids : Metals, hardened concrete

Internal Structure & Chemical Composition Classification
1. Metals : (formed by metallic bonds)
  1. Ferrous (iron, cast iron, steel)
  2. Non-ferrous (aluminum, copper, zinc, lead)
2. Polymers : (long chains having molecules of C, H, O, N which are formed by covalent bonding.)
  1. Natural (rubber, asphalt, resins, wood)
  2. Artificial (plastics)
    
    Natural
    
    Rubber
    
    Natural
    
    Resins
    
    Natural Asphalt
    
    Internal Structure & Chemical Composition Classification
3. Ceramics :
  1. Structural clay products (bricks, tiles, pipes)
  2. Porcelains((
    
    نترب ےک یٹم ینیچ ) is a ceramic
    
    material made by heating materials, generally including kaolin(china clay), in a kiln to temperatures between 1,200 and 1,400 °C)
4. Composite Materials :
  
  (Portland cement concrete)
5. Reinforced Composite Materials :

(reinforced concrete, reinforced plastics)

One of the most important tasks of an engineer is to select the most suitable material for a given civil engineering structure.

Factors Factors Determining the Choice of Proper Material for a Structure

Economy. Choose the cheaper & available materials considering
- Initial cost
- Useful life
- Frequency of maintenance
- Cost of maintenance
- Salvage value etc.

Example: Comparison of Concrete Pavement vs. Asphalt Pavement for economy.

ConcreteAsphaltInitial Cost– (More)+ (Less)Useful Life+(Long life)–(short)Frequency of Repair+(Less)–(More)Cost of Repair–(More)+(Less)Salvage Value-(Less)-(Less)General Properties of Civil Engineering Materials
Physical **

Mechanical **
Chemical
Other

– Thermal, Acoustical, Optical, Electrical

** Most CE Applications focus on physical & mechanical properties

Physical Properties

Properties of physical structure
- Density (mass/volume)
- Specific gravity(ratio of the density of a substance to the density of water – at a specified temperature(4oC)).
- Porosity (Porosity or void fraction is a measure of the void (i.e. “empty”) spaces in a material, and is a fraction of the volume of voids over the total volume, as a percentage between 0 and 100%.)
  
  Physical Properties
  
  PERMEABILTY
  
  Property of a material that lets fluids (such as water or water vapor) to diffuse through it to another medium without being chemically or physically affected.
  
  Mechanical Properties
  - Resistance to applied loads (stress) initially & over time
    - Stiffness
      
      Stiffness is the rigidity of an object — the extent to which it resists deformation in response to an applied force
    - Strength
      
      The capacity of an object to withstand maximum force.
      - Fracture (brittle)
      - Yielding (ductile)

Mechanical Properties

Tension
Compression
Flexure
Torsion

Determining the Properties of Civil Engineering Materials

Properties of materials are determined by
- Laboratory testing
- Field testing
To avoid inconsistencies in test results STANDARDS are devised which describe the test apparatus and the procedure.

Items that are usually standardized in a test are:

Items that are usually
standardized in a test are:
- Obtaining test specimens and number of specimens
- Size and shape of the specimen
- Preparation of specimens for testing
- Temperature & moisture during preparation & testing
- Type of machinery
- Rate of loading
- Interpretation of test results
- Writing a report
  
  Standardization Institutes
  - Turkey – Turkish Standards Institute (TSE)
  - England – British Standards Institute (BSI)
  - Germany – Deutsche Institute Norm (DIN)
  - U.S. – American Society for Testing and Materials (ASTM)
  - Europe – European Committee for Standardization (CEN)
  - India – Indian Standard (IS)
    
    (ASTM)
    
    (ASTM)
    
    CEMENTITIOUS MATERIALS
Although there are several different materials which have adhesive properties, three types are of particular interest to civil engineers.
- Glues : materials of gelatinous nature derived from vegetable or animal sources.
- Bituminous Materials : complex hydrocarbon
- Various Compounds of Calcium : gypsum, lime, cements
Cementitious materials are substances which, upon certain chemical reactions attain binding properties
- Non-hydraulic cements (gypsum and lime)
- Hydraulic cements (portland cement)
Hydraulicity is that property of gaining binding value when mixed with water.

Bridges: Wood

Bridges: Masonry

Stone arch bridge, Mérida, Spain.

1st century

Brick masonry bridge, Kuldiga, Latvia. Originally completed in 1874, destroyed in 1915, rebuilt in 1926.

Bridges: Steel