Building Materials, Third Edition

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called apatites. However, the majority of advanced composite materials with unique properties
are man-made. Straw-reinforced mud bricks for construction of huts, and laminated bows
made from wood, animal, tendons and silk are examples of composites that were in use in
several centuries BC. The most widely used composite material in construction industry is
cement concrete and, reinforced cement concrete. Some of the special concrete such as
Ferrocement and fibre concrete are also composites.
Composite materials are known to have more environmental resistance than traditional civil
engineering materials such as steel, masonry, and plaster. Degradation in strength and stiffness
for steel structures due to the corrosion problem requires frequent inspection, maintenance
and repair. Similarly stress cracking due to warm/cold weathering limits the service life of
concrete structures. Use of composites in structure minimizes property and life loss induced by
earthquake.
Currently, composite materials are being used to retrofit and /or reinforce existing
infrastructure. For example composite have been used to provide an external reinforcement to
concrete columns to increases the earthquake resistance. Similarly, flat composite laminates
may be bonded to the exterior surface of the reinforced concrete deck to increase its bending
stiffness.
Based on the fiber type in the composite, the material can be selected for specific uses. Glass
fibers are used to strengthen polymeric material and composites. Glass fiber reinforced plastics
and glass fibre reinforced cement concrete are the excellent composite material. Alumina nickel
aluminium composites. Carbon fibers are used with epoxy resins or metals such as aluminium
as matrix for compressor blades in gas turbines, high strength to weight ratio is requirement.
Carbon fibers in very small quantity in concrete forms smart concrete, a composite of the era.
Ceramic fibres such as fibers of Al 2 O 3 and SiC are becoming very useful. A variety of metals
e.g., steel can be used to draw high strength wires that may serve as metal fibers.

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1. Briefly describe the properties of following building materials.
   (a) Adhesives (b) Asbestos
   (c) Thermocole


2. (a) What is thermocole?
   (b) How are adhesives classified?
   (c) Give specific uses of linoleum in buildings.


3. Write notes on:
   (a) Heat insulating materials.
   (b) Sound insulating materials.
   (c) Damp proofing materials.


4. What are geosynthetics? Briefly describe their applications in building and construction
   industry.
   1.Briefly describe the properties and uses of following materials
   (a) Heat insulating materials (b) Sound proofing materials
   (c) Water proofing materials (d) Sand-lime bricks
   2.Describe briefly the following materials
   (a) Thermocole (b) Linoleum
   (c) Asbestos (d) Geosynthetics