2015年1月8日星期四

History and Development of construction materials.

Construction steel products hold the balance in construction, which gradually develops according the growth of social productive forces, science and technology. At the earliest time, human lived in caves, when we know nothing about construction materials. And human hadn’t learnt to dig caves and build booth with wood and bamboos until it came to Stone Age, when we could rough houses with raw materials. And then, our ancestors made tiles with clay, made lime with rocks. From that point, building materials turn into man-made phrase from natural phrase, which offered support for building bigger houses. 

After the 18th century, steel, cement, concrete and other construction materials were produced, which laid foundation to modern buildings. Among these, rebar as one of major steel products. 

Rebar, which is short reinforcing steel bar, is a steel bar or mesh of steel wires used as a tension device in reinforced concrete and reinforced masonry structures to strengthen and hold the concrete in tension. Rebar's surface is often patterned to form a better bond with the concrete. — Wikipedia 

It is the most significant steel products for construction, because buildings are held by its strength and tension. Our company supply kinds of steel rebar in standards: BS4449 -1997 Grade 250B, 460B; BS4449-2005 GRADE 500B; GB, HRB335/HRB400/HRB500, CRB550 etc.

For modern construction, the quality and prosperities of construction materials, and if they are applied properly tie closely to the quality of engineering. 

In China and many other countries, after the demolition of a building, workers are called in to remove the rebar. They scour the site, extracting the metal using bolt cutters, welding equipment, sledgehammers, and other tools. The metal is partially straightened, bundled and sold.

Rebar, like almost all metal products, can be recycled as scrap. It is usually combined with other steel products, melted down, and re-formed.

After the twenty century, combining with the enriched of construction materials, chemical material based on organics quickly developed and became popular. Some materials have special functions, such as thermal insulation materials, sound absorption materials, fire-resistant materials, waterproof materials, anti-explosion materials and radiation protection materials, offer firm material guarantee to building protection.