Architecture is an important indicator of the historical development of mankind. With the rise of a nation and civilisation in general the architecture inevitably becomes more advanced and sophisticated; in consequence, building materials evolve too.
Limestone, presumably, was the first building material used by man: lime plates lie in the foundation of the Egyptian pyramids and the Great Wall of China. The strength of ancient masonry structures is provided by the perfect fit for stones – cementing materials, were discovered centuries later. Concrete was invented in ancient Rome – the Romans invented concrete, which, congealing, acquired the strength and durability of the stone. All this has enabled the Romans to create magnificent, monumental castles and palaces.
The role of hydraulic lime in modern building industry
Building projects become way more sophisticated as years pass on, and economic feasibility is no longer the most essential factor even in residential projects. Thus, sophisticated conditions may dictate the requirements for successful implementations, and these requirements drive innovations and changes in production of building technologies and materials.
Therefore, to ensure proper hardness, plaster solutions are used as inorganic binders with water and various additives. Binders also represent construction materials used for the manufacture of concrete and mortar. Binders are used in plaster works and are divided into three main groups: mineral (air and hydraulic); organic, and mixed with special properties.
For the erection of structures in humid operating conditions, as well as for constructing plinths and foundations of large buildings, irrigation canals, preparation of masonry mortar and plaster for use in wet conditions and in the manufacture of lime, ash and lime-slag binders hydraulic lime is widely utilised. This product is obtained by calcining before sintering to marly limestone, contains from 6 to 25% of fine clay and sand admixtures. In accordance with industry standards the result of manufacturing of lime is the fine powder, with sifting residue of particles on the sieve not exceeding 1 – 15%.
Apart from clay impurities hydraulic lime is also comprised of incorporating magnesium carbonate and other impurities. Since the building lime is manufactured from natural raw materials without any additional components, to obtain the artificial mixture of uniform composition marly limestones with uniform distribution of clay and other impurities must be provided. Construction specialists of Telling Company, a far-famed Wolverhampton-based architectural agency widely applying hydraulic lime and lime mortar solutions, admit that not each type is suitable for this or that construction site and individual characteristics have a decisive factor on the choice. The quality of products depends on the form of compounds – limestone or other impurities. Hydraulic lime typically estimated in accordance with a primary or hydraulic module, which is the ratio of percentage of weight of calcium oxide to the percentage of acidic oxides.