Review Notes: Building Materials - Bituminous Materials, Ferrous and Non-Ferrous, Glass & Glazing

BITUMINOUS MATERIALS


Bitumen – a generic name applied to a semisolid mixture of complex hydrocarbons, derived from coal or petroleum, as a coal-tar pitch or asphalt.

Tar – the resulting condensate when destructive distillation is carried out on such materials as wood coal, shale, peat or bone.

Pitch – a solid or semi-solid residue produced from partial evaporation or fractional distillation of tar.

Coal-tar Pitch – most common material of this kind of pitch.

Asphalts - dark brown or black solids or semi-solids which are found in the natural state and are also produced by the refining of petroleum.

Liquid Paving Asphalts – liquid asphalts used for paving are cutbacks.

Asphalt Paving Cements – used as binders for more expensive asphalt pavements.

FERROUS AND NON-FERROUS MATERIALS


Ferrous – metal in which iron is the principal element
Nonferrous – containing no, or very little iron.

Ferrous Metal:

1. Steel – a malleable alloy of iron and carbon produced by melting and refining pig iron and/or scrap steel, graded according to the carbon content.
2. Pig Iron – used to make cast iron which is high in compressive strength but low in tensile strength, and has little use for construction.
3. Wrought Iron – produced when pig iron is melted in such a way as to remove nearly all of the carbon and other impurities.
4. Alloy Steels – made by containing other elements with the molten steel. Nickel, chromium copper and manganese are used.
5. Nickel Steel – stronger than carbon steel and is used to make structural members for building chromium steel is very hard and corrosion-resistant.
6. Stainless Steels – made with chromium or a combination of nickel and chromium used in buildings for exterior wall panels, frames for doors, expansion joints, flashings, copings, fascia and gravel stops.
7. Copper – bearing steel has high resistance to corrosion and is used for making sheet steel and metal lath.
8. Manganese Steel – offers great resistance to abrasion and finds important use in the cutting edges of heavy digging tools.
9. Weathering Steel – recently developed grade of steel. It forms its protection against atmospheric corrosion and thus requires no painting.

Nonferrous Metal:

Aluminum – a lustrous, silver-white nonmagnetic, lightweight metal which is very malleable; has good thermal and electrical conductivity; a good reflector of both heat and light.

Aluminum Foil – used as a vapor barrier on walls and ceilings and as reflective insulation.

Copper – a lustrous reddish metal, highly ductile and malleable; has high tensile strength; is an excellent electrical and thermal conductor; is available in a wide variety of shapes; widely used for downspout, electrical conductors, flashings, gutter, roofing, etc.

Lead – a soft, malleable, heavy metal; has low melting point and a high coefficient of thermal expansion. Very easy to cut and work, enabling it to be fitted over uneven surfaces. Used for roofing, flashing and spandrel wall panels.

Tin – a lustrous white, soft and malleable metal having a low melting point; relatively unaffected by exposure to air; used for making alloys and solder and in coating sheet metal.




GLASS AND GLAZING


Glass – a hard, brittle inorganic substance, ordinarily transparent or translucent; produced by melting a mixture of silica, a flux and a stabilizer.

Types of Glass:

1. Reflective Glass – used to control glare and reduce solar heat. It the product of a glass-coating process which is carried out in a large, rectangular vacuum chamber. Manufactured in two types, silver and gold, the glass can be specified in any one of three nominal light transmittance of 8, 14, or 20 percent.
2. Rolled and Rough Cast Glass – used where clear vision is not required, such as by factory roofs and walls, windows for halls and staircases, skylights, and partitions in offices. Cast glass diffuses light, and because of its low reflecting and absorption index, transmits 90 to 93 percent of light rays striking it.
3. Cathedral and Figured Glass – manufacturing is similar to rolled and rough-cast glasses. However, they contain a pattern or texture impressed usually on one surface by a patterned roller.
4. Wired Glass – simply a rolled glass into which wire mesh is inserted during the process of manufacture.
5. Heat –Absorbing Plate Glass – made by adding ingredients to the mix used in making regular slate glass so that the finished product is pale bluish-green or gray.
6. Tempered Plate Glass – three to five times as strong as regular plate of the same thickness – and area in resisting compressive forces and fracture due to strain or thermal shock.
7. Vitreous Colored Plate – polished plate glass can be heat-strengthened and coated on one side with vitreous color which is fire-fused to the surface.
8. Laminated Safety Glass (Bullet Proofing) – widely used in the automotive industry and transportation, but now finding some uses in the building industry, like glass that can withstand firearm attack and explosions.
9. Insulating Glass – consists of two sheets of plate or sheet glass, separated by an air space, and joined around the edges to produce a hermitically sealed unit.

Classification of Sheet Glass:

1. Window Glass – used for glazing windows doors and storm sash in residential buildings where good light and vision are required at moderate cost.
2. Heavy Sheet Glass – used for glazing windows and doors where greater strength is required but where slight distortion is not objectionable.
3. Picture Glass – used for covering pictures, photographs, maps, charts projector slides and instrument dials.

Glass products:

1. Glass Blocks – comparable in many ways to unit masonry but have the added feature of transmitting light.
2. Solid Glass Brick – also made to admit light into a building, because of its solid construction, it offers greater protection against vandalism than conventional window glass or glass blocks. The ability of the brick is to allow undistorted passage of light.

Posted in: BldgMatls