Anil Kumar Pillai
The Ramco Cements Limited
In today’s construction scenario, HPC (High Performance Concrete) is required for execution of concrete structures. Specific type of concrete is required for each concrete structure based on its location, purpose, exposure conditions and type of structure.
The definition of High Performance Concrete, therefore, will change with the type of concrete structure. It could be a normal residential building, multi-storeyed structure or dams or flyovers or projects of strategic importance.
The performance parameters of concrete required for each segment or project in the construction sector is different. Few of the specific requirements of concrete could be as follows:
1. Concrete with high early strength which can be used for construction of chimneys or silos using specialised formwork technology. One day concrete compressive strength is the key parameter in such projects.
2. Concrete with high slump retention time which could range from 30 minutes to 3 hours for Ready Mix Concrete units
3. Concrete with low heat of hydration for mass concreting works and for concrete requiring lesser thermal stresses.
4. Concrete with high durability especially for structures along marine /coastal areas whose durability can be measured through tests like RCPT (Rapid Chloride Penetration tests) and Water permeability tests
5. Concrete for precast units where moulds needs to be removed at the earliest
6. For underground concrete structures resistance to sulphate and chloride attack is required.
Therefore concrete needs to be customised based on the structure and application. The objective of concrete technologists working in projects with specific requirements as mentioned above is to ensure a concrete with the required compressive strength, workability and durability. High performance concrete therefore does not have a standard or uniform definition; it changes with the type of structure, exposure conditions and specific requirements of concrete in fresh and hardened state.
RAMCO Strongly believes that every market segment in the construction sector requires specific cement for specific application. For example, Ramco Superfast, a Rapid Hardening Portland cement is specifically made for precast segment. Ramco Supercrete is a cement ideal for concreting with high compressive strength and low heat of hydration. Similarly, while RAMCO Supergrade can be used for both concrete and plaster, RAMCO has developed Ramco Superplaster specifically for plastering purposes. Ramco today is proud to offer almost 12 different brands of cement to the consumers apart from offering a variety of brands from the dry mix plant.
Amongst the 12 varieties of cement offered by RAMCO, 4 are Portland Pozzolana Cement (Ramco Supercrete, Ramco Supergrade, Ramco Superfine EFC, Karthick Super Plus), 2 are Portland Slag Cement (Ramco Samudra, Ramco Supersteel), 4 are Ordinary Portland Cement (OPC 53, OPC 53 Infra, OPC 43, OPC 43 Infra), 1 Sulphate Resisting Portland Cement (Ramco Supercoast), 1 Rapid Hardening Portland Cement (Ramco SuperFast)
Today’s consumers are far more knowledgeable and clearly aware of their requirements. They are looking for products whose performance meets their requirements. Therefore, Ramco’s policy of segmenting the market and focusing on RIGHT PRODUCT FOR RIGHT APPLICATION will surely help the construction professionals in making suitable customised concrete.
Cement which is being sold as commodity, therefore, can be customised to specific applications which are required for various types of concrete structures.
Since last few years, the Technical Services team of RAMCO, the MACE division, along with RAMCO RESEARCH DEVELOPMENT CENTRE (RRDC) and Manufacturing team interacted with customers from various segments to clearly identify the concrete requirements of various segments – housing, commercial complexes, Ready Mix Concrete units, Precast units, Infrastructure projects and Projects of strategic importance.
The identification and requirements of concrete for each project must be evaluated based on the grade of concrete required, workability required either through slump or flow test, type of cementitious materials used, type and brand of chemical admixtures used and the degree of durability desired. Moreover the construction practices at various projects also varies, which could range from volumetric batching to batching by weight. Smaller construction sites in rural areas may follow volumetric batching which could lead to errors and hence proper monitoring is required at such sites. Such sites normally do not use chemical admixtures. Most of such sites may not have facilities for checking the compressive strength or workability of concrete. For such sites the Engineers from the Technical Services division of RAMCO – MACE division assist the construction personnel to make concrete of the required performance. There are projects which follows batching by weight where chemical admixtures are used with the overall objective to enhance specific performance of concrete – compressive strength, workability or durability. For all such Projects RAMCO offers Right product for Right application along with data bank of concrete mix designs done at its Research Centre – Ramco Research Development Centre.