This gives the superficial evaluation of the material i.e. shape and size.
Density
The terms density is the mass per unit volume of material in its natural state. The properties of material such as strength, stress and other mechanical, thermal and electrical properties of material etc are greatly influenced by its density. Simply, It is defined as the mass per unit volume, ρ = m/v =Kg/m3 =1000 kg/m3, of water 1 gm/cm3 The term density is sometimes also used for the unit weight. So, Bulk unit weight γ is defined as the total. Weight per unit volume γ = w/v =KN/meter cube =9.81 KN/M3 9810 N/Meter Cube
Specific gravity
It is the ratio of the weight of a given material per unit volume to the weight of water per unit volume (or equal volume) at the given physical condition Sp. Gr = Specific weight of material / Specific weight of water It is also defined as the ratio of the density of a material to the density of water at same physical condition G = ρs / ρw Cement =3.5 Sand=2.6 to 2.9 Steel=7.8to 7.9
Porosity
It is the ratio of volume of voids in the material to the total volume of the material. It depends upon the texture and type of material. Porosity is measure of the denseness or looseness of material.
Porosity = Volume of void Porosity / Total volume
It is expressed in percentage. The porosity of the material is indicative of its various properties such as strength, bulk density, water absorption, permeability, durability etc.
Water Absorption capacity
It is defined as the ratio of absorbed water to the dry weight of the same material in a specific time period. It is measured as in percentage. It depends on the volume, shape, and size of the porous present in the material and type of material.
Water Absorption capacity =Weight of absorbed water / Dry Weight of material
Permeability
The property of a material, which permits flow of water through it, is called permeability. It is measures of water passing across the material per unit surface area perpendicular to the direction of flow. It depends upon type of material, size of material and porosity of the material.
Soundness
It is the physical property of material, which deals with the resistance of the material against the effect of heat and moisture attacks. It also defines as, the material means the resistance of the material against the effect of heat, alternate freezing and thawing moisture attack, etc.
Frost Resistance
It is the resistance of a material to resist against repeated action of freezing and thawing without considerably decreasing the mechanical strength in a saturated condition. The frost resistance of a material depends upon the density of material and degree of saturation with water. The dense materials are generally frost resistant.
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