Whatever you need for your application, toughness or resistance to weathering, Galiawa ensures that all aggregate products are of the highest quality so Galiawa’s aggregates can be relied on by our clients.
At Galiawa, the aggregate solutions available can be split into two major categories:
- Main natural aggregates that are collected from hard rock quarries and sand and gravel deposits.
- Alternative aggregates, made of recycled concrete, and secondary aggregates, such as mining waste, slag, and ashes, from other industrial waste.
What are aggregates?
As in the case of natural sand and gravel, aggregates are rock fragments derived from fluvial deposits or quarried from hard rock formations. The extracted materials are then processed into final products by crushing, shaping, and screening, including washing where necessary. In the manufacture of concrete or bitumen, the processed aggregates can be mixed with cement materials as a binder in the production of asphalt.
|We have world-class cement that is suitable for a broad range of applications. What you need to know about cement is this.|
|1.||What is cement and how is it made?
Cement consists of carefully calibrated quantities of calcium, silica, aluminium and iron which are combined in balanced proportions and then heated to extreme temperatures to create clinker. To create cement, this material is ground into a fine powder. The method provides it with hydraulic characteristics, allowing it to bind sand and gravel together to form concrete.
|2.||Types of cement
In the building industry, there are different kinds of cement used. Depending on its intended use, the material structure and properties differ between each type of cement. Additives are introduced during the manufacturing process to alter things such as strength, curing time, color, and resistance to chemicals.
|3.||The difference between cement and concrete
One of the materials used in the making of concrete is cement. Concrete consists of the cement paste and aggregates. By adding water to cement, the paste is formed, and aggregates are made up of sand or crushed stone. These materials together harden to form the rock-like mass we know as concrete.
Cement products are usually graded by strength, with a higher number suggesting a higher strength, ranging from 35.5, 42.5 and 52.5. The strength class is determined by standard tests performed at either two or seven days, and again at 28 days. The strength class is generally preceded by the letters’ N ‘or’ R ‘, with normal strength indicated by the former, and fast strength gain indicated by the latter.
|5.||How long does cement take to dry?
Within 24 to 48 hours, most cement will set. The curing process will reach partial completion after 7 days. It is necessary to keep the cement free from heavy loads during this process. Construction can proceed afterwards. At 28 days, most cement mixes will be cured fully and maximum strength is reached.
|6.||Shelf life and storage
The shelf life of cement is roughly 6 months inland, and 3 months in coastal areas. This can be impacted, however, by storage conditions. Cement should always be stored in a dry and moisture-proof area. The bags should be stacked on wooden pallets about 20 cm off the floor, in an environment with as few windows as possible.
When dealing with cement, it is important to practice proper precautions. Cement can cause irritation and burns when it comes into contact with the skin because of its alkaline nature. Fine cement powder can also cause damage to the eyes and lungs. Protective equipment is, therefore, required. This entails protection for the eyes, gloves, safety shoes, and protective clothing.