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Effective of Admixture usage in Concrete
Alpha Construction chemical, a leading manufacturer of concrete admixtures and additive in Bangladesh, was established in 2016, in Uttara, Dhaka. It is specialized in concrete admixtures’ and additive research, manufacturing, and distribution. Alpha produces over 40 products, including PC Ether, SNF/PNS, SMF, SAF superplasticizer, set accelerators, set retarders, Air entraining agent, pumping aids, anti-freezing products, etc.
What is concrete damp?
Concrete’s porous nature means that water from under your home can seep up through your concrete floor, making it damp. This can cause issues with mold and mildew, especially if you have carpet or furniture on top of the concrete. Basements and garages – the typical rooms with concrete floors – also suffer from poor air circulation, giving the moisture nowhere to go once it seeps through the floor. Sealing the concrete can help eliminate the dampness on your floor.
How moisture gets into concrete?
Every slab of concrete has moisture and will always have moisture. So you’re never going to achieve, nor would you want, 100 percent dry concrete. What you’re looking for is moisture content that’s at an acceptable level to accept the flooring finish you are going to apply. Moisture sources for concrete are both internal and external. The internal source of moisture is the water mixed with cement that created the concrete. Despite advances in concrete science, the ratio of water to cement in your batch of concrete remains one of the most influential factors as to how long a concrete slab needs to cure and dry. External sources of concrete moisture can also be substantial and include such things as rainwater, poor plumbing, poor drainage below or at the sides of the slab, and even the humidity in the air. Whatever the source, once the concrete slab is poured and cured, it needs enough time for the excess moisture within it to evaporate. If the flooring finish is applied while the concrete retains excess moisture, that’s when you can expect flooring adhesive failures, efflorescence, or other types of moisture-related damage.
How moisture moves through concrete?
During the drying process, the concrete batch water, cement, aggregate, and other admixtures create tiny pathways within called capillaries. Once cured, the excess water in the slab moves through these capillaries to release the moisture. Since most concrete floors have a vapor retarder below them, this moisture must move upwards in order to escape. The significant movement of water within the slab means that the moisture content will vary by depth. Generally, the surface of the slab is drier, while deeper in the concrete, the moisture content is higher. One more important note: Moisture doesn’t just flow out of a slab. The flow of moisture is actually a two-way street. External sources of water present during the drying process can potentially increase a slab’s moisture content. The capillaries in the concrete act like a sponge that can soak up direct water sources.