What Is Density?
Let’s get started with the basics; what is density and density of cement?
Density is also known as the unit weight of a substance which is represented via a symbol called a line (p). It also represents the degree of the material’s compactness and if the material is of higher density, it becomes more compact.
The density of construction materials is mass per unit volume of materials used/in question. They are expressed in kg / ft3 / m3 or lb which shows the compactness of the construction material.
Also expressed as:
- p = m/V = 1/v
Here;
- p = the density [kg / m3]Â [slugs / ft3]
- m = is the mass [kg] [slugs]
- V = the volume [m3] [ft3]
- v = the specific volume [m3 / kg] [ft3 / slug]
- Conversion = 1 kg / m3 which is, 0.624 lb / ft3
Bulk Density Of Cement
Cement works as a binder, that is a substance used in construction which hardens and adheres to other materials and helps join them together. It is rarely used on its own but is best to bond gravel and sand. Cement mixed with fine aggregate produces mortar for masonry, or gravel and sand that produce concrete.
Density is the ratio of mass to volume. This is why it can be indicated in terms of kg / m3, which is about 1440 kg / m3 for cement. Density is found for materials and not certainly for quantities.
Bulk Density Of Sand
The sand’s density returns based on its conditions, by condition, we mean if they are wet, dry, or packaged.
Sand’s density is affected if it is compacted/bulged/loose/wet/dry. Here, when the sand is packed, its grains are forced to form a narrower formation and produce more matter in its volume.
On the other hand, the natural sand which is locally available has a bulk density of 1.71 kg/m3 and is mostly used in construction with a specific gravity of 2.65) with a 5.24 fineness modulus.
When the sand is wet, the water present in it affects the total matter in the volume. Here, the average density of the different sand conditions is as follows:
- Loose sand has a density of 1442 kg / m3. It is dry and has probably been moved or agitated to loosen its natural process of packaging
- Dry sand has a density of 1602 kg / m3. It is in its undisturbed natural form where it has been compacted by gravity and rain over time but is now dry
- Packed sand has a density of 1682 kg / m3. Here the sand is packed manually or mechanicallyÂ
- Wet sand has a density of around 1922 kg / m3. This is the kind of sand that has been in a naturally compressed environment and is now wet
- Wet packed sand has a density of 2082 kg / m3. Here, the sand is compacted and is also almost saturated with water.
Aggregate Density
This is an aggregation of non-metallic minerals that are obtained in the form of particles and can be easily processed and used when constructing civil and road engineering.
Aggregates are mainly classified into two categories:
- Fine aggregate – Is a natural sand kind that has been sieved and washed to remove particles that are larger than 5 mm
- Coarse aggregate – Is gravel that has been crushed, washed, and sieved so that the particles from 5 to 50 mm in size are removed. The coarse and fine aggregate is delivered separately.
Most people opt to use a mixture of both, fine and coarse aggregate by combining them into correct proportions and concrete with very few spaces or voids to reduce the amount of comparatively expensive cement that is needed to produce strong concrete.
Bulk Density Of Aggregate
The density or unit weight of an aggregate is the weight and mass of the aggregate which is needed to fill a container with a specified unit volume.
The bulk density = mass/volume
Here;
- If one unit is the volume, then the bulk density = mass
- Units are in kg / m3 or lb / ft3
The volume in this definition contains the voids and aggregates between the aggregate particles with the approximate apparent density of the aggregate commonly used in normal-weight concrete which is between 1200–1750 kg / m3 that is 75-110 lb / ft3.
The standard test method here for determining the apparent density of aggregates can be presented in the (AASHTO T 19) ASTM C 29 standard.
The Relative Density Of Aggregate
The specific gravity or the relative density of an aggregate is the ratio between the mass of an equal amount of water with the mass.
Relative density = mass of the aggregate/mass with an equal volume of water
Here;
The aggregates will have a relative density which will fall between 2.4-2.9 with a corresponding particle density of mass at 2400-2900 kg / m3 (150-181 lb / ft3).
For coarse aggregates, the standard method is explained in ASTM C 127 (AASHTO), and for the fine aggregates in ASTM C 128 (AASHTO).
Its relative density can be determined with a dry saturated surface (SSD) or oven-dried basis.
Density Of Building Materials As Per IS 875 Part-1
Density of Civil Martials
| Construction Materials | Density (Kg /m3) | Density (lb/ft3) | Density (Kn /m3) |
| Cement | 1440 kg/m3 | 89.8 | 14.4 |
| Ordinary Cement | 1440 kg/m3 | 89.87 | 14.4 |
| Rapid Hardening Cement | 1280 kg/m3 | 79.87 | 12.8 |
| Sandstone | 2000 kg/m3 | 124.8 | 20 |
| Sludge | 2100 kg/m3 | 131 | 21 |
| Concrete (PCC) | 2400 kg/m3 | 149.8 | 24 |
| Concrete (RCC) | 2500 kg/m3 | 156 | 25 |
| Water | 1000 kg/m3 | 62.43 | 10 |
| Saline Water | 1025 kg/m3 | 63.96 | 10.25 |
| Ferry | 170 kg/m3 | 10.6 | 1.7 |
| Bamboo | 300 – 400 kg/m3 | 18.7 – 25 | 3.0 – 4.0 |
| Pine | 370 – 530 kg/m3 | 23 – 33 | 3.7 – 5.3 |
| Cedar | 380 kg/m3 | 23.7 | 3.8 |
| Aspen | 420 kg/m3 | 26.2 | 4.2 |
| Willow wood | 420 kg/m3 | 26.2 | 4.2 |
| African mahogany | 495 – 850 kg/m3 | 31 – 53 | 4.95 – 8.5 |
| Honduras mahogany | 545 kg/m3 | 34 | 5.45 |
| American redwood | 450 kg/m3 | 28 | 4.5 |
| European redwood | 510 kg/m3 | 31.8 | 5.1 |
| Fir (Canadian) | 450 kg/m3 | 28 | 4.5 |
| Fir (Sitka) | 450 kg/m3 | 28 | 4.5 |
| Aphromosia | 7.05 | ||
| apple | 660 – 830 kg/m3 | 1.2 – 51.8 | 6.6 – 8.3 |
| Gray (black) | 540 kg/m3 | 33.7 | 5.4 |
| Gray (white) | 670 kg/m3 | 41.8 | 6.7 |
| Birch | 670 kg/m3Â | 41.8 | 6.7 |
| Ebony | 960 – 1120 kg/m3 | 59.9 – 69.9 | 9.6 – 11.20 |
| Elm | 600 – 815 kg/m3 | 37.4 – 50.8 | 6.0 – 8.15 |
| Iroko | 655 kg/m3 | 40.9 | 6.55 |
| Larch | 590 kg/m3 | 36.8 | 5.9 |
| Maple | 755 kg/m3 | 47.1 | 7.55 |
| Carvalho | 590 – 930 kg/m3 | 36.8 – 58 | 5.9 – 9.30 |
| Teak | 630 kg/m3 | 9.3 | 6.3 |
| Sycamore | 590 kg/m3 | 36.8 | 5.9 |
| Lignum vitae | 1280 – 1370 kg/m3 | 79.9 – 85.5 | 12.80 – 13.70 |
| Sandy soil | 1800 kg/m3 | 112.3 | 18 |
| Clay soil | 1900 kg/m3 | 118.6 | 19 |
| Gravel soil | 2000 kg/m3 | 124.8 | 20 |
| Chalk | 2100 kg/m3 | 131 | 21 |
| Shale | 2500 kg/m3Â | 156 | 25 |
| Sedimentary rocks | 2600 kg/m3 | 162.3 | 26 |
| Metamorphic rocks | 2700 kg/m3 | 168.5 | 27 |
| Igneous (felsic) rocks | 2700 kg/m3 | 168.5 | 27 |
| Igneous (mafic) rocks | 3000 kg/m3 | 187.2 | 30 |
| Bricks | 1500 – 1800 kg/m3 | 93.6 – 112.3 | 15.00 – 18.00 |
| Asphalt | 721 kg/m3 | 45 | 7.21 |
| Lima | 640 kg/m3 | 39.9 | 6.4 |
| Cement mortar | 2080 kg/m3 | 129.8 | 20.8 |
| Lime mortar | 1760 kg/m3 | 109.8 | 17.6 |
| Steel | 7850 kg/m3 | 490 | 78.5 |
| Stainless steel | 7480 – 8000 kg/m3 | 466.9 – 499.4 | 74.80 – 80.00 |
| Aluminium | 2739 kg/m3 | 170.9 | 27.39 |
| Magnesium | 1738 kg/m3 | 108.4 | 17.38 |
| Cobalt | 8746 kg/m3 | 545.9 | 87.46 |
| Nickel | 8908 kg/m3 | 556.1 | 89.08 |
| Tin | 7280 kg/m3 | 454.4 | 72.8 |
| Lead | 11340 kg/m3 | 707.9 | 113.4 |
| Zinc | 7135 kg/m3 | 445.4 | 71.35 |
| Cast iron | 7208 kg/m3 | 449.9 | 72.08 |
| Copper | 8940 kg/m3 | 558.1 | 89.4 |
| Iron | 7850 kg/m3 | 490 | 78.5 |
| Glass | 2580 kg/m3 | 161 | 25.8 |
| Bitumen | 1040 kg/m3 | 64.896 | 10.4 |
| Brick Dust (Surkhi) | 1010 kg/m3 | 63.024 | 10.1 |
| Clay Soil | 1900 kg/m3 | 118.56 | 19 |
| Earth (Dry) | 1410 – 1840 kg/m3 | 87.98 – 114.82 | 14.10 – 18.40 |
| Earth (Moist) | 1600 – 2000 kg/m3 | 99.84 – 124.8 | 16.00 – 20.00 |
| Fire Bricks | 2400 kg/m3 | 149.76 | 24 |
| Granite Stone | 2400 – 2690 kg/m3 | 149.76 – 167.85 | 24.00 – 26.90 |
| Gypsum Mortar | 1200 kg/m3 | 74.88 | 12 |
| Gypsum Powder | 1410 – 1760 kg/m3 | 87.98 – 109.82 | 14.10 – 17.60 |
| Ice | 920 kg/m3 | 57.41 | 9.2 |
| Plain Cement Concrete | 2400 kg/m3 | 149.8 | 24 |
| Reinforced Cement Concrete | 2500 kg/m3 | 156 | 25 |
| Prestressed Cement Concrete | 2400 kg/m3 | 149.8 | 24 |
| RCC Blocks | 2100 kg/m3 | 131.04 | 21 |
| Rubber | 1300 kg/m3 | 81.12 | 13 |
| Sal Wood | 865 kg/m3 | 53.98 | 8.65 |
| Sand (Dry) | 1540 – 1600 kg/m3 | 96.09 – 99.84 | 15.40 – 16.00 |
| Sand (Wet) | 1760 – 2000 kg/m3 | 109.82 – 124.80 | 17.60 – 20.00 |
| Stone Ballast | 1720 kg/m3 | 107.33 | 17.2 |
| Stone chips | 1600 – 1920 kg/m3 | 99.84 – 119.81 | 16.00 – 19.20 |
The density also decides the sinking property of any material by knowing the density of the liquid. This means that if a material has a lower density than the liquid then it would float on the surface. Simultaneously, if it is denser as compared to the liquid, then it would sink.
On the flip side, if two different materials have similar weights, the density of both will be different. Lower dense material occupies more volume as compared to the ones with higher dense material.
The value of the building material density can also help discover the amount of material needed for a space.
For instance, water has a density of 1000kg / m3 and if we put a wood made from bamboo (350kg / m3) into the water, then it will float on the surface as compared to the brick (1700 kg.m3) which is the sink.
