Product & Services

  • Ready Mixed Concrete
  • Transport and Pumping
  • Technical Services
  • FAQ's

At RDC Concrete, ready mixed concrete (ready mix concrete or RMC) is produced in its fully automated and computerized concrete batching plants at multiple locations across India. RDC Concrete manufactures and supplies concrete mixes, which are designed in its well-equipped laboratories as per established procedures to comply with various provisions of Indian Standards. RDC Concrete's experienced logistics team works closely with you to ensure that the concrete of requisite quality is delivered on time and in the appropriate quantities.

RDC Concrete has the experience and the ability to design, produce and deliver a wide range of ready mixed concrete variants to meet specific requirements. Do contact us with details of your requirements and our experts will get in touch with you to discuss the way forward.

Apart from concrete mixes of various grades, RDC Concrete also produces special concretes.

Our Other Special Concrete Solutions :

FiberCrete Fibre Reinforced Concrete Download Brochure
ImpriCrete Decorative Concrete Download Brochure
LiteCrete Light Weight Concrete Download Brochure
NatureCrete Pervious Concrete Download Brochure
ProCrete Workability Retaining Concrete Download Brochure
SelfCrete Cohesive Flowable Concrete Download Brochure
SelfCrete+ Self Compacting Concrete Download Brochure
TempCrete Temperature Controlled Concrete Download Brochure

Benefits of ready mixed concrete over Site Mixed Concrete

Quality

RMC produced from fully automated batching plants guarantees quality since:

The raw materials are subject to stringent quality and quantity measures.

The concrete is subject to quality control throughout the manufacturing and delivery process.

Diversity of solutions

A wide variety of ready mixed concrete can be produced, with ease and on demand, by varying the proportions/combinations of the cement, aggregates and admixtures.

Service

Ready mixed concrete provides customers with unique service quality due to:

the availability of a large number of concrete mixer trucks which enable delivery rates to be kept under control.

supply of special services for difficult worksites like pumps, conveyors, etc.

the ability to adapt the pace of deliveries to the customer's needs.

Cost-effectiveness

Ready mixed concrete is more cost effective because:

Basic materials are now not stored on site and this reduces the need for storage space.

Plant and machinery for mixing concrete are not required.

Wastage of basic materials is avoided.

Labor associated with production of concrete is reduced.

Time required for the entire process is greatly reduced.

Lower Pollution

The use of RMC reduces air pollution in and around the worksite as the mixing is done at the plant.

Transport

To ensure speedy and efficient delivery, the RDC Concrete team will survey the site to ensure that the transit mixer trucks will have unimpaired access to the site. Among the factors they will consider are:

The access road and ground condition up to the discharge point should be safe and good enough for heavy vehicles.

Sufficient turning space should be provided for the transit mixer to access and leave the delivery point.

The distances, heights and clearances should be sufficient for moving the equipment.

Pumping Concrete

Pumping is one of the most efficient means of pouring concrete. In many situations-such as in high rise buildings - pumping is the only viable option. At other times, the ease and speed of pumping concrete makes it the most economical method of pouring concrete.

Ready mixed concrete is available in many variants; each of which has unique properties and uses. Whether your project is still in the planning stage, or you are experiencing concreting difficulties, the RDC team will work with you to understand your needs and deliver the most appropriate concrete products and services.

Fresh concrete needs attention and protection till it achieves sufficient strength and maturity. In the absence of proper care, concrete could develop defects that possibly cannot be rectified at later stage. The RDC's technical experts work with customers to ensure best practices for the proper use and maintenance of concrete are followed so that the resultant structure's strength, maturity and durability are ensured .

Make Your Concrete Last Longer

Here are a few tips that will enable you to ensure that concrete remains good throughout its intended lifespan:

Ordering ready mixed concrete

Do consult a qualified structural designer to determine the grade of concrete required for your structure. Ensure that the RDC technical team is informed about the correct grade of concrete along with other relevant details (specific contractual requirements or suggestions from the structural designer).

Formwork (Shuttering and Centering)

A properly constructed formwork is the cornerstone of a reliable concrete structure. Do have the formwork inspected and approved by a qualified structural designer before pouring the concrete. Here are a few guidelines that will help you build quality formworks:

  • For formwork of ground floor slabs, the props should rest on firm surface, preferably PCC. When the formwork is rested on earth, ensure that the ground is dry and well compacted. Use spreaders for props resting on ground.
  • Avoid the use of wooden props if possible; steel supports are preferred.
  • For slabs, ensure that props are vertical. Load carrying capacity reduces significantly when props are inclined.
  • To fix props, use bracings on both sides and runners at the center.
  • Seal any gaps in shutter joints to avoid leakage of cement slurry.
  • Before concrete is poured, ensure that interiors of the forms (shutters) are cleaned and shuttering oil (form release agent) is applied. Avoid the use of engine oil or other such lubricants as they may stain the concrete surface.
  • During concreting, forms, props, and all other supports must be continuously checked
  • After concreting, do consult your structural designer before removing the formwork. Listed in the table below are the recommended time limits as defined in IS 456:2000, 'Plain & Reinforced Concrete - Code of Practice'
  • Type of Formwork Minimum Period
    Vertical formwork of columns/walls/beams 16-24 hours
    Props for slabs with span up to 4.5 m 7 days
    Props for Slabs with span over 4.5 m 14 days
    Props for beams/arches with span up to 6 m 14 days
    Props for beams/arches with span over 6 m 21 days

    Reinforcement

  • Rough handling, shock loading and dropping of steel from a height should be avoided.
  • Avoid the use of wooden props if possible; steel supports are preferred.
  • Reinforcement should be free of rust, scales and coats of mud, oil or any other substances that may reduce or destroy the bond between steel and concrete.
  • Rebending and straightening of torsteel should preferably be avoided.
  • Do have the reinforcement checked by the structural designer after it is placed and secured.
  • The cover is the distance between the reinforcement and the concrete surface and is vital in ensuring the durability of the structure. Listed in the table below are the nominal minimum cover recommendations as defined in IS 456:2000, 'Plain & Reinforced Concrete - Code of Practice'.
  • Cover blocks should be of concrete or mortar of same strength or of PVC.
  • Structure Minimum Cover
    For all concrete works in slabs, beams etc 20 mm
    For longitudinal reinforcing bars in column 40 mm
    For columns with minimum dimension of 200 mm or less with maximum bar diameter of 12 mm 25 mm
    For footings 50 mm

    Placing of Concrete

    Improper placing of concrete could result in a defective structure that may require expensive repairs. While placing concrete, do ensure that:

    The concrete is deposited in or very near to its final position.

    The concrete is not placed in large heaps on the formwork. Moving heaped concrete manually or with a vibrator should also be avoided.

    The concrete is poured vertically from a height of less than one meter; otherwise it may lead to segregation.

    In mass concrete works, the concrete is placed in uniform layers; sloped layers may lead to segregation.

    When thickness/depth of structure is more than 300 mm (1 foot), concrete is placed in two or more layers of equal thickness/depth. In general, the allowable thickness of each concrete layer ranges from 150 mm (6 inches) to 300 mm (1 foot).

    In layered construction, fresh layer of concrete is placed only after the lower layer is properly compacted, but before that layer has set. If the continuity in placement is not maintained, it will lead to the formation of cold joints that will weaken the structure.

    For slabs, concrete placement starts from the corners and ends, and then continues inwards.

    There is no displacement of reinforcement and/or damage to formworks.

    For large concrete pours, proper planning and co-ordination are crucial in avoiding delays, cold joints, or segregation.

    When concrete is being poured into deep sections with heavy/congested reinforcement, ensure sufficient visibility so as to ensure proper placement of concrete. Inadequate care in placing may lead to segregation, poor finish and honeycombing effect, particularly in the lower portions of the structure.

    Compaction of Concrete

    Concrete, unless it is specifically designed for self-compaction, must be compacted. Compacting concrete removes the entrapped air and voids, and consequently increases the strength and durability of the concrete. To achieve uniformly compacted dense concrete:

    In the general construction of slabs, beams and columns, use needle vibrators of 50 mm diameter. For thin sections, in confined locations, and in structures with congested reinforcement, use a 30 mm diameter needle vibrator.

    Ensure adequate supply of spare vibrators and adequate fuel at the site.

    The concrete surface being compacted must be visible.

    The needle should be inserted quickly and allowed to quickly and completely penetrate the concrete on its own weight.

    The needle should not be left in the concrete for more than 10 seconds. If the concrete is being pumped, it will have a slump of 80-120 mm; in this case, the needle should not be left in the concrete for more than 5 seconds. Over vibration may cause mortar to accumulate on the top with the resultant thin layer having poor strength.

    Use experienced operators to man vibrators; they can determine when adequate compaction is achieved. Typical signs of sufficient compaction are air bubbles on the surface and the constant drone of the needle vibrator.

    Withdraw the needle from concrete slowly to ensure that the hole left by the needle is filled.

    Insert needles in staggered fashion to ensure uniform compaction for the concrete.

    In a layered placement, the needle should penetrate the bottom layer by 80-100 mm.

    For compaction in hot weather (for concreting of slabs), use a light initial vibration and then another round of vibration after about 30 minutes; this helps in significantly reducing shrinkage cracks.

    If concrete segregates due to over vibration, fine aggregates tend to accumulate on concrete surface and there is a tendency to shrink and crack. To avoid this, plough up and mix coarse aggregates with the help of forks (punja) before finishing.

    Wherever construction joint is to be provided, stop-ends should be firmly fixed to avoid movement of joints and ensure proper compaction of the concrete near stop-ends.

    Curing of Concrete

    Curing of concrete, which helps retain water in concrete that may have evaporated due to prevailing high ambient temperatures and/or windy conditions, is the last but significant step in concrete construction. Inadequate curing can result in concrete of poor strength and durability.

    Curing is generally done by sprinkling or spraying of water, by ponding or immersion, and by covering exposed surfaces with wet jute or hessian cloth. For slabs, ponding is the best method of curing. For effective curing of concrete, do ensure that:

    Continuous and adequate supply of water is available at the site throughout the curing period.

    The exposed concrete surfaces are kept in the wet or damp condition for at least 10 days from the date of placing concrete. Curing for 14 days would be ideal.

    In hot weather, curing by sprinkling of water is started within 4 to 5 hours of batching of concrete and continued till bunds are prepared and ponding is done.

    In some cases, when the temperature is above 30°C and strong winds are blowing, concrete surfaces may dry very fast inducing plastic shrinkage cracks as early as within 30 minutes of concrete placing. In such a situation, trowel the cracked concrete surface while it is still plastic to erase the cracks and then ensure that the concrete surface is continuously kept wet.

    Curing water and material used for bunds are free of substances which may stain or discolor concrete.

    Preferably cement mortar is used to prepare of bunds instead of earth.

    Bunds for ponding of water are maintained throughout the curing period.

    The height of bunds is sufficient for the ponding water to cover entire area uniformly including corners and edges. To avoid dry spots, water should be ponded for at least 20 mm above the highest point of concrete surface.

    For sloped roofs, staircases, columns and other vertical surfaces, cover the entire surface with hessian or jute cloth which is saturated with water throughout the curing period.

    Apparent ready mixed concrete shortages are caused by:

    Miscalculation of form volume or slab thickness when actual dimensions exceed the assumed dimensions by even a fraction.

    Deflection or distortion of the formwork.

    Irregular subgrade and its settlement.

    Smaller quantities wasted or used in incidental works for large pours.

    To ensure sufficient supply of ready mixed concrete:

    Measure formwork accurately and order sufficient quantity to finish the job.

    For large pours, include an allowance of about 2% over planned dimensions to account for wastage, potential increased thickness, etc.

    Towards the end of large pours, carefully measure the remaining volume and confirm the closing quantity to the ready mixed concrete supplier.

    NO! Restrain masons at the site. Do not force Transit Mixer Operators to add water to ready mixed concrete. Consequences of such actions can be severe. Properly designed ready mixed concrete contains optimum water. Inform the ready mixed concrete supplier if workability (slump) of ready mixed concrete is not as expected. If required, dosing of admixtures along with a small quantity of water would be done by the ready mixed concrete supplier´s technical personnel.

    Ready mixed concrete mixes are supplied only after exhaustive laboratory and plant trials.

    To ensure consistent quality, incoming raw materials are regularly tested. Sampling and testing of ready mixed concrete is done everyday as per Codal stipulations. At RDC Concrete, we invite you to visit our laboratories to witness the process.

    The transit mixers are about 9 m long, 2.5 m wide and 3.8 m high

    A truck weighs 10 tons when it is empty and 25 tons when it is fully loaded with ready mixed concrete.

    RDC Concrete can deliver a minimum load size of 1 cubic meter.

    During winters: Depending on the workability, the ready mixed concrete might be usable for up to 3 hours.

    During summers: In hot weather, ready mixed concrete may start stiffening within an hour, depending on the prevailing ambient temperature. If the ready mixed concrete dries faster, sprinkling with water or curing compounds is required to prevent the cracking of the plastic surface.

    Indian Standards specify that ready mixed concrete must be discharged from the transit mixer truck within 2 hours of the time of loading. It is also mandatory to make arrangements at site to ensure that full load of ready mixed concrete is discharged within 30 minutes of arrival on site.

    When the ready mixed concrete is transported to the construction site, the ready mixed concrete is pushed deeper into the drum attached to the back of the truck with the help of a spiral blade fitted within the drum. This is achieved by rotating the drum in one direction. This process is known as charging the transit mixer.

    At the construction site, the drum is rotated in the other direction, which forces the ready mixed concrete out of the drum. This process is known as discharging. The ready mixed concrete may be discharged directly into chutes, pumps or on to conveyor belts.

    Pumps are designed to facilitate pumping of ready mixed concrete through the pipeline under high hydraulic pressure. When ready mixed concrete is pushed through the pipeline, it is separated from pipe line wall by a lubricating layer of cement, water and fine aggregates. Ready mixed concrete should have enough cohesiveness and workability for the mix to move easily through pipeline, bends, reducers and hoses.