Sand is one of the most fundamental materials in construction, playing a crucial role in building homes, infrastructure, and forming concrete.
While vast reserves of sand exist in seas and deserts, these types are unsuitable for construction. The question arises: why is that?
Despite the sheer abundance of sand in these environments, what prevents us from using it?
The role of sand in construction
Sand serves as an essential component in nearly every stage of construction, from mixing concrete to masonry work. For a structure to be strong, durable, and long-lasting, the right type of sand must be carefully chosen.
While sand can be sourced from various locations, river sand remains the preferred material in many countries.
Why river sand is the go-to choice
In countries like Bangladesh, river sand is the dominant material used for construction projects. Its abundant supply and ideal characteristics make it a reliable option for cement mixing and building sturdy structures. However, concerns about excessive or illegal extraction of river sand have been frequently highlighted in media reports.
Key characteristics of sand in construction
Not all sand is created equal when it comes to construction. Before sand can be used, it must meet certain criteria regarding size, shape, and texture. Sand is typically classified into three categories based on particle size: coarse, medium, and fine.
The strength and durability of a structure depend on these factors. Rough, angular particles, for example, are far superior in terms of resistance and bonding strength compared to smooth, rounded particles.
Why sea and desert sand don’t make the cut
Sea and desert sands fall short of the qualities needed for reliable construction.
Sea sand, for instance, is typically smooth and fine, with rounded particles that hinder the creation of strong chemical bonds during construction. Even when mixed with cement, these particles fail to form a durable bond, making the resulting structure weak. Additionally, sea sand contains salt, which accelerates corrosion in steel and iron, further compromising the structural integrity.
Desert sand presents similar challenges. Its particles are too smooth and round to form the necessary interlocking bonds with cement, which are crucial for creating a solid structure. Furthermore, desert sand tends to have high salt and alkaline content, which weakens the structure over time as water evaporates, causing the bonds within the concrete to deteriorate.
This is why despite their abundance, neither sea nor desert sand meets the criteria necessary for use in construction.
River sand, with its angular and rough texture, remains the most suitable and widely used option for building durable and stable structures. Recognizing the importance of selecting the right type of sand is essential for ensuring that buildings and infrastructures stand the test of time, delivering both safety and longevity.
