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Cellular Light Weight Concrete

CLC is called as Cellular Light Weight Concrete and it is alsovcalled as Foam Concrete. Cellular Light Weight Concrete (CLC) is a version of light weight concrete that is produced like normal concrete under ambient conditions.

Are you worried about rising construction costs of projects ?

If yes, then CLC blocks is your answer. CLC blocks area cement-bonded material made by blending slurry of cement. Stable, pre-formed foam manufactured on site is injected into this slurry to form foam concrete. Fresh foam concrete looks like a milk-shake and the volume of slurry in the foam dictates the cast density of the foam concrete.

Procedure of Making CLC

Aqueous foam is produced from the foam generators (IFG) and injected into slurry of cement, fly ash and water in foam concrete mixture (IFM). It creates many small air cells which are uniformly distributed throughout the concrete and create cellular from 300kg/m3 to 1800kg/m3 with compressive strength between 5kg/cm2 to 200kg/cm2. The volume of air cells in foam concrete determines the density and strength.

The final mixture is then used for different applications without any vibration or compaction. The foam concrete is thus a green building material.

Advantages

• Light in Weight : CLC blocks are very lightweight with density ranging from 300 to 1800 Kg/m3. Three times less weight then clay or fly ash brocks.

• Eco friendly : CLC blocks are Environment-friendly. Foam concrete is eco- friendly material as fly ash and other industrial waste material are used in part of manufacturing blocks to protect the environment. The production process of CLC or its use does not release any harmful effluents to ground, water or air. CLC, due to its low weight is ideal for making partitions. The use of CLC for this purpose will reduce the need for plywood partitions. This consequently will result in reduction in deforestation and will benefit environment.

• Sound Insulation : CLC Blocks are excellent for Sound insulation which keeps the house cool in Summer and warm in Winter saving energy/electricity for cooling and heating. It is possible to achieve even higher values depending upon the thickness of block.

• Thermal Insulation : Thermal insulations as a 100mm thick CLC wall, the equivalent thickness of dense concrete wall would have to be more than 5 times thicker and 10 times heavier.

• Lower Water Absorption : The water absorption of this material is relatively lower than any other materials. This compares much better than concrete 50% and ordinary brick, which has water absorption of around 50% to 80%. The low water absorption property of these blocks will help to reduce the cracks in the walls.

• Fire Protection : Foam concrete blocks offers great fire protection. With just a 100mm thickness of wall with density of 1000 kg/m3, offers fire endurance for heat transmission for 4 hours without releasing any toxic fumes during the fire. Fire rating of cellular concrete is far superior to that of brickwork or dense concrete.

• Easy to Handling : Foam concrete blocks are easy and quick to install, thus minimizing construction costs.For more information visit our website:

http://sanghicement.com

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Self Compacting Concrete

self-compacting concrete (SCC) is a flowing concrete mixture that is able to consolidate under its own weight. The highly fluid nature of SCC makes it suitable for placing in difficult conditions and in sections with congested reinforcement. Use of SCC can also help to minimize hearing-related damages on the worksite that are induced by vibration of concrete. Another advantage of SCC is that the time required to place large sections is considerably reduced. MIX DESIGN OF SELF COMPACTING CONCRETE (SCC) Self Compacting Concrete has to be designed and tested before it is produced and used for construction. During SCC evaluation, the local materials and equipments have to be tested to find out the right concrete mix proportions and mixing times suitable for the element to be cast. Various kinds of fillers can result in different strength, shrinkage and creep but shrinkage and creep will usually not be higher than for traditional vibrated concrete.

A flow-chart describing the procedure for design of SCC mix is shown in Figure below:

General Requirements in the Mix Design of SCC 1. A high volume of paste: The friction between the aggregate limits the spreading and the filling ability of SCC. This is the why SCC contains a high volume of paste (cement + additions +efficient water + air), typically 330 to 400 l/m³, the role of which is to maintain aggregate separation.

2. A high volume of the particles (<80µm): In order to ensure sufficient workability while limiting the risk of segregation or bleeding, SCC contains a large amount of fine particles (around500 kg/m³). Nevertheless, in order to avoid excessive heat generation, the Portland cement is generally partially replaced by mineral admixtures like flyash (cement should not be used as a filler). The nature and the amount of filler added are chosen in order to comply with the strength & durability requirements.

3. A high dosage of super plasticizer: Super plasticizers are introduced in SCC to obtain the fluidity. Nevertheless a high dosage near the saturation amount can increases the proneness of the concrete to segregate.

4. The possible use of viscosity agent (water retainer): These products are generally cellulose derivatives, polysaccharides or colloidal suspensions. These products have the same role as the fine particles, minimizing bleeding and coarse aggregate segregation by thickening the paste and retaining the water in the skeleton.The introduction of such products in SCC seems to be justified in the case of SCC with the high water to binder ratio (for e.g. residential building). On the other hand, they may be less useful for high performance SCC (strength higher than 50MPa) with low water to binder ratio.

For more information visit our website: http://www.sanghicement.com

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cement industry in india

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The company sells Ordinary Portland Cement (OPC53 & OPC43), Portland Pozzolana Cement (PPC), and Portland Slag Cement (PSC) in Indian Markets of Gujarat, Rajasthan, Maharashtra and Kerala and International Markets of Middle East, Africa and the Indian Sub-continent. It also sells Ready Mix Concrete (RMC) in Ahmedabad and Rajkot markets.

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Sanghi Industries Limited

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Sanghi Industries Limited is among leading cement manufacturers from Western India. Sanghi Cement's 4.1 million tonnes per annum capacity plant Located in Kutch, Gujarat is one of the largest single location cement plant in India.

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The company sells Ordinary Portland Cement (OPC53 & OPC43), Portland Pozzolana Cement (PPC), and Portland Slag Cement (PSC) in Indian Markets of Gujarat, Rajasthan, Maharashtra and Kerala and International Markets of Middle East, Africa and the Indian Sub-continent. It also sells Ready Mix Concrete (RMC) in Ahmedabad and Rajkot markets.

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Sanghi Industries Limited

Sanghi Industries Limited is among leading cement manufacturers from Western India. Sanghi Cement's 4.1 million tonnes per annum capacity plant Located in Kutch, Gujarat is one of the largest single location cement plant in India. Equipped with multi-fuel technology from FLSmidth, this fully integrated plant includes captive facilities viz. a Thermal Power Plant, all weather Port and Sea terminals at Gujarat and Mumbai. The company possesses one of the largest limestone reserves in the country along with other additive mines like Laterite and Silica Sand. Due to high quality of its mineral reserves and advanced manufacturing technology, Sanghi is able to produce superior grade of Cement while maintaining one of the lowest cost of production. It has got the distinction of being a Five Star Rated Cement company with Certifications for Quality, Environment, Health & Safety, Testing & Collaboration and Social Accountability.For more information visit our website:   http://www.sanghicement.com  

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Sanghi Industries Limited is among leading cement manufacturers from Western India. Sanghi Cement's 4.1 million tonnes per annum capacity plant Located in Kutch, Gujarat is one of the largest single location cement plant in India. Equipped with multi-fuel technology from FLSmidth, this fully integrated plant includes captive facilities viz. a Thermal Power Plant, all weather Port and Sea terminals at Gujarat and Mumbai. The company possesses one of the largest limestone reserves in the country along with other additive mines like Laterite and Silica Sand. Due to high quality of its mineral reserves and advanced manufacturing technology, Sanghi is able to produce superior grade of Cement while maintaining one of the lowest cost of production. It has got the distinction of being a Five Star Rated Cement company with Certifications for Quality, Environment, Health & Safety, Testing & Collaboration and Social Accountability.

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Know what Polymer Modified Concrete is and its Applications

Concrete with polymers added during mixing to modify properties of hardened concrete are polymer modified cement concrete (PMC).

Polymers are added to the concrete mixes either in the form of an aqueous emulsion or in a dispersed form. This is to improve the following properties of concrete: 1. The extensibility and the tensile strength of the concrete structure 2. The impact resistance 3. The Abrasion resistance 4. The durability and the resistance to the aggressive fluids 5. The bond between the old and the new concrete

The polymer modified cement concrete is a composite that is obtained by the incorporation of a polymeric material into the concrete. This is carried out during the mixing stage. The polymers that are incorporated at this stage should in no way interfere with the hydration process. Since many polymers are insoluble in water, their addition can only be carried out in the form of emulsion or dispersion or in the form of latex. The composite formed is then cast into the required shape in the conventional manner of construction. Later the curing is carried out similar to normal concrete curing. The hydrated cement and the polymer film is formed due to the curing of the polymeric material constitute an interpenetrating matrix that binds the aggregate. The polymeric materials in the form of lattice and prepolymers may be added to modify the cement concretes. The quantities of polymers required for polymer modified concrete are relatively small. This range from 1 to 4% by mass of the composite. Polymer modified concrete is least expensive. The processing of PMC is found to be very simple.

Types of Polymer Modified Concrete (PMC) Based on the type of the modifier used, polymer modified concrete can be classified into the following types: 1. Latex-Modified Cement Concrete 2. Pre-Polymer Modified Cement Concrete

Latex-Modified Cement Concrete

The lattices are white milk like suspensions that consist of very small sized polymer particles, that are suspended in water with the help of emulsifiers and stabilizing agents. It contains about 50% of polymer solid by mass. Both elastomeric and glassy polymers have been employed in the lattices for modifying cement concrete. These impart high modulus of elasticity, higher strength and low rate of corrosion of the reinforcement. The latex admixtures can be stored in an adequate exposure that helps the mixture to be protected against the freezing and temperature exposures.

Prepolymers-Modified Cement Concrete

The polyester-styrene based system, epoxy system and the furan system etc. are used for this. The strength improvement of this type of PMC is of the order of 50-100% over the conventional concrete.

Properties of Polymer Modified Concrete

The properties of Polymer modified concrete are explained below:

The addition of polymers makes the concrete mix to become more workable. This can hence reduce the amount of water that is added to the concrete mix.

The crushing strength of the concrete is increased using the polymer in concrete. This is because the polymer reduces the water cement ratio which in turn increase the crushing strength.

The bond between the aggregate and the matrix is improved.

The polymer modification increases the flexural strength of the concrete.

The polymer modified concrete consist of at least 3 % more amount of entrained air than the plain concrete. This additional amount of entrained air will reduce the modulus of elasticity of the concrete (PMC).

The polymer addition increases the setting time of concrete.

The resistance of the concrete against abrasion is increased using the polymer.

Freezing and thawing resistance of the concrete structure is improved by polymer modification.

The penetration of chlorine ions and other deleterious materials is restricted. 

With the help of best quality cement the PMC gain higher resistance against such undesirable effects.

The PMC gains superior shear bond strength.

The ductility property of the polymer modified concrete is more compared with the conventional concrete.

These gain a superior tensile and flexural strength compared to the conventional concrete.

Applications of Polymer Modified Concrete

• The polymer modified concrete can be used in the repair and the rehabilitation of old damaged concrete. • The floor construction in frozen – food factories gains great application. This is because of the higher freeze and thaw resistance of PMCs. • For floor construction of factories were chances of the splitting of chemicals and oils more prone to happen. • For the preparation of steel bridge and ship decks surfaces. • For the concrete structure that is more subjected to large doses of de-icing salts. • For the cementing ceramic tiles to concrete.

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How Poor Construction Methods and Workmanship Could Be Disastrous

Poor construction methods and workmanship is responsible for the failure of buildings and structure. The poor construction methods and workmanship is caused due to negligence and inadequate quality control at construction site. The effects of some of the poor construction methods are as under :

(a) Incorrect Placement of Steel

Incorrect placement of steel can result in insufficient cover, leading to corrosion of the reinforcement. If the bars are placed grossly out of position or in the wrong position, collapse can occur when the element is fully loaded.

(b) Inadequate over to reinforcement

Inadequate cover to reinforcement permits ingress of moisture, gases and other substances and leads to corrosion of the reinforcement and cracking and spalling of the concrete.

(c) Incorrectly made Construction Joints

The main faults in construction joints are lack of preparation and poor compaction. The old concrete should be washed and a layer of rich concrete laid before pouring is continued. Poor joints allow ingress of moisture and staining of the concrete face.

(d) Grout Leakage

Grout leakage occurs where formwork joints do not fit together properly. The result is a porous area of concrete that has little or no cement and fine aggregate. All form work joints should be properly sealed.

(e) Poor Compaction

If concrete is not properly compacted by ramming or vibration the result is a portion of porous honeycomb concrete. This part must be hacked out and recast. If Complete compaction is essential to give a dense,impermeable concrete. Usage of good quality cement also plays a vital role in compaction

(f) Segregation

Segregation occurs when the mix ingredients become separated. It is the result of

Dropping the mix through too great a height in placing (chutes or pipes should be used in such cases)

Using a harsh mix with high coarse aggregate content

Large aggregate sinking due to over-vibration or use of too much plasticizer Segregation results in uneven concrete texture, or porous concrete in some cases.

(g) Poor Curing

A poor curing procedure can result in loss of water through evaporation. This can cause a reduction in strength if there is not sufficient water for complete hydration of the cement. Loss of water can cause shrinkage cracking. During curing the concrete should be kept damp and covered.

(h) Too High a Water Content

Excess water increases work ability but decreases the strength and increases the porosity and permeability of the hardened concrete, which can lead to corrosion of the reinforcement. The correct water-tocement ratio for the mix should be strictly enforced.