A material's life cycle can be organized into three phases: Pre-Building; Building; and Post-Building. The basic ingredients for building products, whether for concrete walls or roofing membranes, are obtained by mining or harvesting natural resources. In reality, a material is only considered a renewable or sustainable resource if it can be grown at a rate that meets or exceeds the rate of human consumption. Some sustainable building materials rely on new technology, others reinvigorate centuries-old methods. The latter have a track record that makes performance easier to anticipate and evaluate. New technologies require testing over time. Advice from other architects and building owners who are using these new technologies can assist in determining their long-range effectiveness. (Sharma 18-20)
Physical properties includes density, melting and boiling temperature. Mechanical Properties includes basic mechanical properties, such as elastic modulus, shear modulus, Poisson's ratio, and mechanical strength properties, i.e., yielding stress, ultimate stress, elongation. Thermal Properties includes Coefficient of thermal expansion and thermal conductivity. Electric Properties includes Electric resistivity. Acoustic Properties includes Compression wave velocity, shear wave velocity and bar velocity.
Asphalt is a dark brown to black cementitious material in which the predominating constituents are bitumens that occur in nature or are obtained in petroleum processing. Asphalts are highly complex and not well-characterized materials containing saturated and unsaturated aliphatic and aromatic compounds with up to 150 carbon atoms. Their composition varies depending on the source of crude oil. Many of the compounds contain oxygen, nitrogen, sulfur, and other heteroatoms. Asphalt typically contains about 80% by weight of carbon; around 10% hydrogen; up to 6% sulfur; small amounts of oxygen and nitrogen; and trace amounts of metals such as iron, nickel, and vanadium. The molecular weights of the constituent compounds range from several hundred to many thousands. Asphalt Physical Properties are a direct result of its chemical composition..
Within a certain temperature range an asphalt is also viscoelastic, which means that it exhibits the mechanical characteristics of viscous flow and elastic deformation. Generally, asphalts are characterized by their physical properties.
Softening Point: Range of temperatures that the asphalt softens using a ring and
ball technique. Sometimes thought of as the melting point.
Penetration How far a weighted needle or cone will sink into the asphalt during
a set period of time.
Viscosity An indication of how thick or thin the liquid asphalt is at various
Flash Point Temperature that the heated asphalt will ignite.
The softening point and penetration are usually the most commonly used measurements for classifying an asphalt's properties. Generally, when comparing asphalts, as the softening point increases, the viscosity also increases, the penetration drops and the flash point rises. The widespread use of asphalt relies on its remarkable waterproofing and binding properties. Asphalt is used for Buildup Roofing, Waterproofing, Damp-roofing, Rubberized Joint Sealer,