What Is Unit Weight?
The ratio of the weight of a material to its volume is its unit weight, sometimes termed specific weight or weight density. The unit weight of water, γw, is 9.81 kN/m3 in the SI system and 62.4 lb/ft3 in the English system.
What Is Density?
The term density is used herein to denote the mass-to-volume ratio of the material. However, some references, particularly older ones, use the term to describe unit weight. Density is denoted by p. Because m = W/g, the unit weight terms defined above can be converted to mass densities as follows:
ρ = M/V
ρ = Density
M = Mass
V = Volume
In the SI system mass densities are commonly expressed in Mg/m3, kg/m3, or g/ml. The mass density of water can therefore be expressed ρw = 1000 kg/m3 = 1 Mg/m3 = 1 g/ml.
The mass density of soil solids typically ranges from 2640 to 2750 kg/m3. Where mass or mass density values (g, kg, or kg/m3) are given or measured, they must be multiplied by g(9.8 m/s2) to obtain weights or unit weights before performing stress calculations.
In the English system mass density values are virtually never used in geotechnical engineering and all work is performed in terms of unit weights (1b/ft3).
What Is Unit Weight Material?
Unit weight material is also known as Specific material weight. Unit weight material is the weight of the material per unit volume. As we know that the volume is identified in terms of liters or m3 and weight is measured in terms of Kg or KN.
The unit weight of materials is the weight of material/unit volume which means the Unit weight is expressed in Kg/L or KG/m3 or KN/m3. For easy reference, we organized all the building materials unit weights in a table. This list is a collective effort. Give a thumbs up if you liked it. Bookmark the page and use the search if required.
Unit Weight Building Materials
Sr.No.
|
Material
|
Unit Weight
|
| 1 | A.C Sheet | 17 Kg/m3 |
| 2 | Aerocon Bricks | 551 to 600 Kg/m3 |
| 3 | Alcohol | 780 Kg/m3 |
| 4 | Aluminum | 2739 Kg/m3 |
| 5 | Anthracite Coal | 1550 Kg/m3 |
| 6 | Ashes | 650 Kg/m3 |
| 7 | Ballast | 1720 Kg/m3 |
| 8 | Birch Wood | 670 Kg/m3 |
| 9 | Bitumen | 1040 Kg/m3 |
| 10 | Bituminous concrete | 2243 Kg/m3 |
| 11 | Bituminous Macadum | 2400 Kg/m3 |
| 12 | Brick | 1600 – 1920 Kg/m3 |
| 13 | Brick Jelly | 1420 Kg/m3 |
| 14 | Brick Masonry | 1920 Kg/m3 |
| 15 | Cast iron | 7203 Kg/m3 |
| 16 | Ceement Slurry | 1442 Kg/m3 |
| 17 | Cement Concrete block | 1800 Kg/m3 |
| 18 | Cement Grout | 1500 to 1800 Kg/m3 |
| 19 | Cement Mortar | 2000 Kg/m3 |
| 20 | Cement Plaster | 2000 Kg/m3 |
| 21 | Cemrent | 1400 Kg/m3 |
| 22 | Chalk | 2220 Kg/m3 |
| 23 | Clay (Damp) | 1760 Kg/m3 |
| 24 | Clay (dry) | 1600 Kg/m3 |
| 25 | Clinker | 750 Kg/m3 |
| 26 | Coal Tar | 1200 Kg/m3 |
| 27 | Coarse Aggregate | 1680-1750 Kg/m3 |
| 28 | Cobalt | 8746 Kg/m3 |
| 29 | Copper | 8940 Kg/m3 |
| 30 | Crude Oil | 880 Kg/m3 |
| 31 | Cuddapa | 2720 Kg/m3 |
| 32 | Disel | 745 Kg/m3 |
| 33 | Dry Rubble Masonry | 2080 Kg/m3 |
| 34 | Earth (Dry,loose) | 1200 Kg/m3 |
| 35 | Fly Ash | 1120 to 1500 Kg/m3 |
| 36 | Fly Ash Brick Masonry | 2000 to 2100 Kg/m3 |
| 37 | Fly Ash Bricks | 1468 to 1700 Kg/m3 |
| 38 | Galvanized Iron Steel (0.56 mm) | 5 Kg/m3 |
| 39 | Galvanized Iron Steel (1.63 mm) | 13 Kg/m3 |
| 40 | Gasoline | 670 Kg/m3 |
| 41 | GeoPolimer Concrete | 2400 Kg/m3 |
| 42 | Glass Reinforced Concrete | 2000 to 2100 Kg/m3 |
| 43 | Granite Stone | 2460-2800 Kg/m3 |
| 44 | Graphite | 1200 Kg/m3 |
| 45 | Gravel Soil | 2000 Kg/m3 |
| 46 | Green Concrete | 2315 to 2499 Kg/m3 |
| 47 | Heavy Charcoal | 530 Kg/m3 |
| 48 | Ice | 910 Kg/m3 |
| 49 | Igneous rocks (Felsic) | 2700 Kg/m3 |
| 50 | Igneous rocks (Mafic) | 3000 Kg/m3 |
| 51 | Kerosene | 800 Kg/m3 |
| 52 | Larch Wood | 590 Kg/m3 |
| 53 | Laterite Stone | 1019 g/m3 |
| 54 | Lead | 11340 Kg/m3 |
| 55 | Light Charcoal | 300 Kg/m3 |
| 56 | Light Weight Concrete | 800 to 1000 Kg/m3 |
| 57 | Lime Concrete | 1900 Kg/m3 |
| 58 | Lime Plaster | 1700 Kg/m3 |
| 59 | Lime Stone | 2400 – 2720 Kg/m3 |
| 60 | M Sand | 1540 Kg/m3 |
| 61 | Magnesium | 1738 Kg/m3 |
| 62 | Mahogany | 545 Kg/m3 |
| 63 | Mangalore Tiles with Battens | 65 Kg/m3 |
| 64 | Maple | 755 Kg/m3 |
| 65 | Marble Stone | 2620 Kg/m3 |
| 66 | Metamorphic rocks | 2700 Kg/m3 |
| 67 | Mud | 1600-1920 Kg/m3 |
| 68 | Nickel | 8908 Kg/m3 |
| 69 | Nitric Acid (91 percent) | 1510 Kg/m3 |
| 70 | Oak | 730 Kg/m3 |
| 71 | Peat | 750 Kg/m3 |
| 72 | Petrol | 720 Kg/m3 |
| 73 | Pitch | 1100 Kg/m3 |
| 74 | Plain Cement Concrete | 2300 Kg/m3 |
| 75 | Plaster of Paris | 881 Kg/m3 |
| 76 | Plastics | 1250 Kg/m3 |
| 77 | Quarry Dust | 1300 to 1450 Kg/m3 |
| 78 | Quartz | 2320 Kg/m3 |
| 79 | Quick lime | 33450 Kg/m3 |
| 80 | Rapid Hardening Cement | 1250 Kg/m3 |
| 81 | Red Wood | 450-510 Kg/m3 |
| 82 | Reinforced Cement Concrete | 2400 Kg/m3 |
| 83 | Rubber | 1300 Kg/m3 |
| 84 | Rubble stone | 1600-1750 Kg/m3 |
| 85 | Sal Wood | 990 Kg/m3 |
| 86 | Sand | 1440-1700 Kg/m3 |
| 87 | Sandstone | 2250 to 2400 Kg/m3 |
| 88 | Sedimentary rocks | 2600 Kg/m3 |
| 89 | Shale Gas | 2500 Kg/m3 |
| 90 | Silt | 2100 Kg/m3 |
| 91 | Slag | 1500 Kg/m3 |
| 92 | Stainless Steel | 7480 Kg/m3 |
| 93 | Steel | 7850 Kg/m3 |
| 94 | Sulphuric Acid (87 Percent) | 1790 Kg/m3 |
| 95 | Teak | 630-720 Kg/m3 |
| 96 | Tin | 7280 Kg/m3 |
| 97 | Water | 1000 Kg/m3 |
| 98 | Zinc | 7135 Kg/m3 |
FAQ
What Is Unit Weight?
Unit weight, also known as specific weight or weight density, is the ratio of the weight of a material to its volume. In the SI system, the unit weight of water is 9.81 kN/m³, and in the English system, it’s 62.4 lb/ft³.
How Is Density Different from Unit Weight?
Density refers to the mass-to-volume ratio of a material, denoted by ρ. It is calculated as ρ = M/V, where M is mass and V is volume. Unit weight, on the other hand, is the weight per unit volume and is used primarily in geotechnical engineering.
How Do You Convert Unit Weight to Density?
To convert unit weight to density, use the formula ρ = γ/g, where γ is the unit weight and g is the acceleration due to gravity (approximately 9.8 m/s²). For example, a unit weight of 10 kN/m³ converts to a density of 10,000 kg/m³.
What Are Common Units for Expressing Density?
Density is commonly expressed in units such as kg/m³, g/cm³, or Mg/m³ in the SI system, and lb/ft³ or lb/in³ in the English system.
What Are Typical Unit Weights for Building Materials?
The unit weight of building materials varies widely. For example, cement concrete has a unit weight of about 2400 kg/m³, while lightweight concrete can range from 800 to 1000 kg/m³.
Why Is It Important to Know the Unit Weight of Materials?
Knowing the unit weight of materials is crucial for various engineering calculations, including load-bearing capacity, structural design, and material handling. It helps ensure that structures are designed safely and efficiently.
How Does the Unit Weight of Soil Impact Construction?
The unit weight of soil affects its compaction, stability, and bearing capacity. Engineers use this information to assess soil properties and design foundations and other structural elements accordingly.
How Do Environmental Factors Affect Unit Weight and Density?
Environmental factors such as moisture content, temperature, and pressure can affect both unit weight and density. For example, the unit weight of soil can increase with moisture content due to the added weight of water.
What Is the Significance of Mass Density in Geotechnical Engineering?
In geotechnical engineering, mass density is used to understand soil and rock properties, which are critical for foundation design, slope stability, and other structural assessments.
Can Unit Weight and Density Values Vary for the Same Material?
Yes, unit weight and density values can vary for the same material depending on factors such as compaction, moisture content, and impurities. For instance, the unit weight of soil can differ based on its compaction level.
