quiz

• The engineering structures are composed of materials. These materials are known as the engineering materials or building materials or materials of construction.
• It is necessary for the civil engineer to become conversant with the properties of such materials.
• The service conditions of buildings demand a wide range of materials and various properties

  • water resistance
  • strength
  • durability
  • temperature resistance
  • appearance
  • permeability
• The factors which form the basis of various systems of classifications of materials in material science and engineering

  • the chemical composition of the material
  • the mode of the occurrence of the material in the nature
  • the refining and the manufacturing process to which the material is subjected prior it acquires the required properties
  • the atomic and crystalline structure of material
  • the industrial and technical use of the material
• Civil Engineering structures where construction materials are used

  • Buildings
  • Bridges
  • Highways
  • Railways
  • Tunnels
  • Dams
  • Harbor structures
  • Towers
• Civil Engineering Materials


  • Wood
  • Cement and concrete
  • Bitumen and bituminous materials
  • Structural clay, masonry
  • Reinforcing and structural steels
• Concrete


  Construction material, Mixture of Portland cement, water, aggregates, and in some cases, admixtures. The cement and water form a paste that hardens and bonds the aggregates together.
• Composition of Concrete


  • Water
  • Aggregates
  • Chemical admixtures
  • Cement
• Water


  Good water is essential for quality concrete. Should be good enough to drink, free of trash, organic matter and excessive chemicals and/or minerals. The strength and other properties of concrete are highly dependent on the amount of water and the water-cement ratio.
• Aggregates


  Aggregates occupy 60 to 80 percent of the volume of concrete. Sand, gravel and crushed stone are the primary aggregates used. All aggregates must be essentially free of silt and/or organic matter.
• Chemical Admixtures


  Materials in the form of powder or fluids that are added to the concrete to give it certain characteristics not obtainable with plain concrete mixes. In normal use, admixture dosages are less than 5% by mass of cement, and are added to the concrete at the time of batching/mixing.
• The most common types of admixtures

  • Accelerators: Speed up the hydration (hardening) of the concrete. Typical materials used are CaCl2 and NaCl.
  • Acrylic Retarders: Slow the hydration of concrete and are used in large or difficult pours. Typical retarder is table sugar, or sucrose (C12H22O11)
  • Air Entraining agents: The most commonly used admixtures for agricultural concrete. Produce microscopic air bubbles throughout the concrete.
  • Water-reducing admixtures: Increase the workability of plastic or "fresh" concrete, allowing it to be placed more easily, with less consolidating effort. High-range waterreducing admixtures are a class of water-reducing admixtures
• Concrete is strong in compression, as the aggregate efficiently carries the compression load, weak in tension as the cement holding the aggregate in place can crack, allowing the structure to fail. Reinforced concrete solves these problems by adding either metal reinforcing bars, steel fibers, glass fiber, or plastic fiber to carry tensile loads.
• Cement


  Crystalline compound of calcium silicates and other calcium compounds having hydraulic properties. Considered hydraulic because of their ability to set and harden under or with excess water through the hydration of the cement's chemical compounds or minerals.
• Hydraulic Cements


  • Hydraulic lime: Only used in specialized mortars. Made from calcination of clay-rich limestones
  • Natural cements: Misleadingly called Roman. It is made from argillaceous limestones or interbedded limestone and clay or shale, with few raw materials. Because they were found to be inferior to Portland, most plants switched
  • Portland cement: Artificial cement. Made by the mixing clinker with gypsum in a 95:5 ratio
  • Portland-limestone cements: Large amounts (6% to 35%) of ground limestone have been added as a filler to a Portland cement base
  • Blended cements: Mix of Portland cement with one or more SCM (supplementary cementitious materials) like pozzolanic additives
  • Pozzolan-lime cements: Original Roman cements. Only a small quantity is manufactured in the U.S. Mix of pozzolans with lime
  • Masonry cements: Portland cement where other materials have been added primarily to impart plasticity
  • Aluminous cements: Limestones and bauxite are the main raw materials. Used for refractory applications (such as cementing furnace bricks) and certain applications where rapid hardening is required. It is more expensive than Portland
• Portland Cement


  Most active component of concrete, The greatest unit cost in concrete, Its selection and proper use are important in obtaining most economically the balance of properties desired for any particular concrete mixture. The production process for portland cement first involves grinding limestone or chalk and alumina and silica from shale or clay.
• Types of Portland Cement

  • Type I/II Portland cements are the most popular cements used by concrete producers
  • Type I cement is the general-purpose cement and most common type. Unless an alternative is specified, Type I is usually used.
  • Type II cement releases less heat during hardening. It is more suitable for projects involving large masses of concrete--heavy retaining walls.
• Standards


  • PNS – Philippine National Standard
  • ASTM – American Society for Testing and Materials
  • ISO – International Organization for Standardization
  • EN – European Standard
  • DIN – Deutsches Institut für Normung
  • JIS – Japanese Industrial Standards
• Ferrous Metal


  Any metal that contains iron
• Non-Ferrous Metal


  • Metals that don't contain iron
  • More malleable and lighter than ferrous metals
  • Particularly suited for use where strength is required but weight needs to be considered, such as in the aircraft industry
• Types of metals


  • Ferrous metals
  • Non-ferrous metals
• Pure metal


  An element (e.g. iron, copper, gold)
• Examples of ferrous metals

  • Steel
  • Cast iron
  • Wrought iron
• Steel


  • A combination of iron and carbon, renowned for its strength and machinability
  • Widely used in construction, manufacturing and industrial metal fabrication
• Stainless Steel


  An alloy steel made with the addition of chromium to steel, which provides resistance against rust
• Carbon Steel


  Contains a high carbon content that is added to iron to create an exceptionally hard metal that is used for tools
• Cast Iron


  A hard and wear resistant metal that is widely used for items including cookware, machine tools, engines, manhole covers and water pipes
• Wrought Iron


  • Unlike most other ferrous metals, wrought iron is able to resist corrosion and oxidation
  • Typically used for fences, railings and gates
• Rust


  The oxidation of iron that has been exposed to air and moisture
• Non-ferrous metals


  • Includes aluminum, copper, lead, zinc and tin, silver, and gold
  • Their main advantage is their malleability, no iron content giving them higher resistance to rust and corrosion
  • Ideal for gutters, liquid pipes, roofing and outdoor signs
  • Non-magnetic, for electronic and wiring applications
  • Used in Aircraft Frames, Automotive Applications, Appliances, Marine Technology, Hydro Power, Electrical Wiring, etc.
• Copper


  • Red in color, highly ductile, malleable and has high conductivity for electricity and heat
  • Principally used in the electric industry
• Lead


  • Soft, heavy, malleable metal with a low melting point and low tensile strength
  • Can withstand corrosion from moisture and many acids
  • Used in electrical power cables, batteries, building construction and soldering
• Zinc


  • Medium to low strength metal with a very low melting point
  • Used in galvanizing (the process of applying a protective zinc coating to iron or steel to prevent rust)
• Tin


  • Very soft, and malleable, ductile with low tensile strength
  • Often used to coat steel to prevent corrosion (e.g. Tin cans, tin foil in 19th Century)
• Aluminum


  • Lightweight
  • Corrosion Resistant
  • Electrical and thermal conductivity
  • Ductility
  • Strength at low temperature
  • Impermeable and odorless
  • Non-magnetic
  • Non-toxic
  • Sound and shock absorbent
  • Non-sparking
  • Recyclability