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How to calculate the Number of Concrete Blocks in the Wall?

There are various methods for calculating the number of blocks in the wall. In this article, we will see two simple methods for calculating the number of blocks used in the wall.

1. Surface Area Method
2. Volume Method

How to calculate the number of Blocks by Surface Area Method?

1. The surface area of the wall
2. Surface area of the standard concrete block
3. The surface area of openings in the wall

Step 1

The Length & Height of the Wal

Take as Length of the wall = 10 feet

The height of the wall = 10 feet

Step 2

Now calculate the surface area of the wall

Surface Area = Length x Height

Surface Area of the wall = 10 x 10 = 100 sq. feet.

Step 3

Now calculate the Surface Area of Openings

The openings like a door, windows, etc.

Let the wall has window 3’ x 3’

Surface area of the window = 3 x 3 = 9 sq. ft

Step 4

Now subtract the openings from the surface area of the Wall

Final surface area = 100-9= 91 sq. feet

Step 5

Now calculate the surface area of concrete block with mortar

The standard block is 16” x 8” x 8” and mortar allowance is 1”

Surface area of block with mortar = (16+1) x (8+1) = 153 inch²

153/12 x 12 = 1.0625 sq. ft

Step 6

Now divide the total surface area of the wall by the surface area of one block

Number of blocks= surface area of Wall/Surface area of the block

91/1.0625=86

Now consider 5% wastage of concrete blocks

Total number of blocks required = 86 + (86 x 5/100) = 86 + 4 = 90

Now calculate by Volume Method

1. The volume of the wall
2. Volume of the standard concrete block
3. The volume of the openings in the wall

Step 1

First determine the Width, Height, and Thickness of the Wall

Width of the wall = 10 feet

Height of the wall = 10 feet

Thickness of the wall = 8” = 0.67 feet. (Thickness of wall is the same as the thickness of one concrete block)

Step 2

Now the calculate the volume of the wall

Volume = Width x Height x Thickness

Volume of the wall = 10 x 10 x 0.67 = 67 cubic feet

Step 3

The volume of the Openings

The openings like a door, windows, etc.,

Now calculate the volume of the window = 3 x 3 x 0.67 = 6 cubic feet

Step 4

Subtract the volume of the Openings from Volume of Walls

Final Volume of wall = 67 – 6 = 61 cubic feet

Step 5

Now calculate the volume of the concrete block with the Mortar allowance

The concrete block is 16” x 8” x 8” and mortar allowance is 1”

The volume of one block with mortar = (16+1) x (8+1) x 8 = 1224 inch³ (Mortar is applied on upper and one side of every block)

1224/12 x 12 x 12 = 0.70 cubic feet

Step 6

Divide the total volume of a wall by volume of one block

Number of blocks = Volume of Wall/ Volume of Block

61/0.70 = 86

Now consider 5% wastage of concrete blocks

Total number of blocks required = 86 + (86 x 5/100) = 86 + 4 = 90

Note that if there are no openings in the wall, skip step 4.

Different Types of Walls

There are various types of walls.

1. Load Bearing Wall

The wall is designed to carry on imposed the vertical load addition with its own weight together for any load known as the load-bearing wall.

2. Partition Wall

The partition wall is an interior non-load bearing wall. The height of the partition wall is one storey or part of one story. The use of the partition wall is to divide larger space into smaller spaces.

3. Panel Wall

This is an exterior non-load-bearing wall framed construction. This is totally supported at each storey but subjected to lateral loads.

4. Cavity Wall

The wall has two leaves and each leaf is built of masonry units and separated by a cavity and tied together with metal ties or bonding units to ensure that two leaves act as one structural unit. There is space between the leaves in left as a continuous cavity or filled with non-load bearing insulating and waterproofing material.

5. Faced Wall

This is the wall facing and backing of two different materials are bonded together for ensuring common action under load.

6. Veneered Wall

This is the wall where facing is attached to the backing but it is not bonded as resulted in a common action under load.

Defects of Brick Masonry and How to Solve it

The common defects of brick masonry are described below.

Sulphate

The sulphate salt is present in the brickwork and it reacts with alumina content of cement and hydraulic lime in lime mortar and it causes a noticeable increase in the volume of the mortar. The result of this is the chipping and spalling of the bricks and form cracks in joints and rendering.

This defect occurs in where brickwork is exposed to boundary walls, parapets, etc. or it is in contact with the moisture like manholes, retaining walls, etc.

This problem is solved by using suitable construction and choosing materials that stop the moisture to enter in the brick work.

Crystallization of Salts in Bricks

The defects occur in the masonry made from bricks having excessive soluble salts. When the brick comes in contact with the water the soluble salts are dissolved and it appears in the form crystals on the brick surface. This is also called efflorescence.

This defect causes the disfigured the brickwork and makes look ugly of the brick. The efflorescence is solved by brushing and washing of surface repeatedly.

Corrosion of Iron or Steel

The iron and steel used in brickwork get corroded in the presence of dampness. With corrosion the metal expands in volume and also it can crack the brickwork.

The problem can be solved by encasing the reinforcement or iron in dense cement mortar and provides a cover of 15 to 25 mm around the embedded of steel.

Shrinkage on Drying

The brickwork is swelling with water absorption and shrinks when the water evaporates. The cracks are formed in the masonry joints when it shrinks. If there is a lean mortar is used the cracks are distributed over a large number of joints and if there is a rich mortar there are few cracks but they are wider. These cracks do not affect the structural strength of brickwork and it is easily improved.

All these problems can be solved with excellent quality bricks and protect it from the moisture.

The Strength of the Brick Masonry

The strength of the brick masonry is highly dependent on the strength of the bricks used in construction of a structure. Also, the strength of brick is depending on the soil used for making bricks, method, process, and burning of the bricks. As the nature of the soil is different in various regions the average strength of the bricks is also different in various regions.

Also, the permissible compressive stress of brick masonry depends upon several factors like

1. Types of Bricks (1^st Class, 2^nd Class, 3^rd Class)

2. Strength of Bricks

3. Size and Shape of construction

4. Mixing of Mortar

5. Uniformity of Bricks

6. Workmanship

7. Method used for laying bricks

There are various checklists which are applied for increasing strength of brick masonry

1. Visual Check

The brick used for masonry has to be good quality, burnt well with uniform shape, size, and color

2. The metallic sound should be produced by striking two bricks with each other

3. A high-quality brick should not break if it is dropped from one-meter height

4. The good quality brick should not absorb water more than 20% (by its weight) as it submerged in water for 24 hours

Where is the Concrete Beams use?

Concrete beams are manufactured fast which increase the speed of construction. The concrete beams and slabs are made in the same machine with a simple change in cast.

The main advantage of the using hollow-core slabs and prestressed beams are they are high-quality pieces, which saves material and labor. These are high resistance against fire and are easy to transport and assemble.

Where are the concrete slabs and beams are used?

1. Shopping Centres and Superstores

Herewith the hollow slabs you can construct mezzanine systems to support the vertical loads and distribute the horizontal loads equally. The hollow-core slabs are used for divide walls, enclosing walls, facades, etc.

2. Auditorium and University Lecture Halls

Along with structural elements, the L-shaped hollow core slabs also be used to construct grandstands.

3. Car Parks

The hollow cores divide the floors equally and also reduce the number of support sections, so with the fewer columns there is more space to use.

4. Housing Blocks

Hollow core slabs are used to suspended flooring.

5. Industrial Warehouse

Here the slabs are used to enclosing walls. Slabs are included for windows and doors.

ईंट बनाने के लिए कितने प्रकार की मशीनें आती है और उनकी कीमत क्या है ?

आज के टाइम में अच्छी पढाई करने के बावजूद मनचाही नौकरी नहीं मील पाती है। हर कोई अपना खुद का बिज़नेस शुरू करना चाहता है लेकिन बिज़नेस स्टार्ट करने के लिए उनके पास न तो दमदार आईडिया होता है और कई बार तो अच्छा आईडिया होने के बावजूद जमा पूंजी न होने के कारण वे बिज़नेस स्टार्ट नहीं कर पाते।

अगर आप भी अपना खुद का बिज़नेस स्टार्ट करना चाहते है तो यह पोस्ट को अंत तक पढ़े। अगर आप भी अपना खुद का बिज़नेस स्टार्ट करना चाहते है तो आप फ्लाई ऐश ईंटे या कंक्रीट की ईंटे एवं ब्लॉक बनाने का  बिज़नेस शुरू कर सकते है।

यदि आप घर बना रहे है या फिर कोई बड़ी ईमारत, इनको बनाने के लिए ईंटे इस्तेमाल होती है। आप ईंट बनाके बेचने का बिज़नेस शुरू कर सकते है। यह बिज़नेस के जरिए आप फ्लाई ऐश ईंटे, कंक्रीट ब्लॉक और ब्रिक, कंक्रीट पेवर बना के अच्छे दामों पर बेच के मुनाफा कमा सकते है।

अगर हम ईंटो की बात करे तो ईंटे कई प्रकार की होती है जैसे की मिट्टी की ईंटे, फ्लाई ऐश ईंटे, सीमेंट से बनने वाली ईंटे इत्यादि।

यदि आप बिहार में रहते है तो आपको पता होगा की बिहार में लाल ईंटो पर सम्पूर्ण प्रतिबन्ध है तो आप यहाँ पर फ्लाई ऐश की ईंटे बनाने का बिज़नेस स्टार्ट कर के अच्छा मुनाफा कमा सकते है।

ईंटे बनाने की मशीने मुख्य रूप से दो प्रकार की होती है। सेमि – ऑटोमैटिक और फूली ऑटोमैटिक

ईंटे बना ने की अलग अलग मशीनें

• हाइड्रोलिक ब्रिक मेकिंग मशीन
• क्ले ब्रिक मेकिंग मशीन
• सीमेंट ब्रिक मेकिंग मशीन
• इंटरलॉक ब्रिक मेकिंग मशीन
• हॉलो ब्लॉक मेकिंग मशीन
• CLC ब्लॉक मेकिंग मशीन
• कंक्रीट ब्लॉक मेकिंग मशीन

फ्लाई ऐश ब्रिक मेकिंग मशीन – Fly Ash Brick Making Machine

ईंटे बनाने की मशीन के फ़ायदे

1. ईंट बनाने वाली मशीन से काम मेहनत में ज्यादा ईंटे बनाई जा सकती है।
2. ईंटे बनाने वाली मशीन से एक दिन में करीब 20,000 से ले के 50,000 ईंटे बनाई जा सकती है।
3. मशीन से ईंट बनाने में कम समय में ज्यादा ईंटे बनती है।
4. मशीन से ईंटे कम लगत में बनती है जिसे ज्यादा मुनाफा कमाया जा सकता है।

अभी भारत में मशीन से ईंटे बनाने का बिज़नेस तेजी से बढ़ रहा है।

अगर हम ईंट बनाने की मशीन की क़ीमत की बात करे तो यह रोजाना ईंट बनाने की क्षमता, सेमी -आटोमेटिक या फूली आटोमेटिक, मशीन का प्रकार इत्यादि पर निर्भर है।

अगर हम ईंट बनाने की मशीन की कीमत की बार करे तो फ्लाई ऐश ब्रिक बनाने की मशीन की कीमत 10 लाख से शुरू होती है और कंक्रीट ब्लॉक या ब्रिक मेकिंग मशीन की कीमत 20 लाख से शुरू होती है।

अगर आप भी अपना खुद का बिज़नेस शुरू करना कहते है आज ही Q Green Techon PVT LTD से संपर्क करे।

What is Green Building Centre?

In this, we provide information about how ACC’s Green Building Centre works and how you can start your business. We are associate with ACC as machine providers.

The main purpose of ACC’s Green Building Centre is to provide sustainability. According to ACC’s sustainable development 2030 plan, focus on Climate, Circular Economy, Water & Nature, and People & Communities. And for this ACC has developed a model for rural and semi-urban for promoting sustainable construction via a business model that provides affordable and green building materials.
This Green Building Centre, a unique initiative that is supported by ACC, and it provide the best opportunity for rural entrepreneurship and independence. ACC’s Green Building Centre is a sustainable business model that provides a durable and affordable housing solution for rural customers and with that, they can live better.

About the Green Building Centre

This green building center is three in one model to deliver social, environmental and financial performance. This center becomes a one-stop-shop for eco-friendly and high-quality building materials and services and also you can make a partnership with local entrepreneurs. All these available under one roof and operated by ACC’s associates with a franchise-based model. ACC supervises this in layout, safety measures, machine capacity, and design, quality control labs and more.

Products

There are a wide range of products are made with like

• Wall solutions like Fly Ash Bricks, Coloured Bricks, Cellular Light Weight Concrete (CLC) Bricks, Hollow Blocks, Solid Blocks, Pre Cast Walls
• Pavement solutions like Paver Blocks, Chequered Tiles, Kerb Stones, Garden Bench, Cover Blocks
• Concrete Door & Window Frames
• Roofing Solutions

Advantages

With this green building project, all solutions come under one roof and all components are affordable, eco-friendly housing and sanitation for rural and semi-urban India. This provides all manufacturing materials and products and provides services at a single location and this increases customer experience.
This encourages the entrepreneurship of people, creates employment, training and skill development for masons and labors in a rural area. Also, this promotes water harvesting and preservation. There is energy generation while manufacturing eco-friendly cement bricks, blocks, roofing solutions, and aggregates. With this project there are thirty livelihoods are created directly and 120 livelihoods created indirectly.
The goal of this project is to build 1 million affordable houses and toilets in rural India in the next 10 years.
We have successfully installed many machines within this project. We support green building and to work on this more effectively we have a wide range of machines for making various cement products like cement blocks, bricks, hollow and solid blocks, concrete pavers, Kurb stones, CLC blocks, etc.

What is Cellular Concrete?

The cellular cement is a specially engineered concrete manufactured by mixing the Portland cement, sand, fly ash, water, and pre-formed foam in various proportions to form a hardened material having an oven-dry density of 50 pounds per cubic foot (PCF) or less.

As per the definition by ACI, the density of cellular concrete must be lesser than 50 pounds per cubic foot. The cellular concrete has a density of 20 PCF to 120 PCF.

The important characteristic of cellular concrete is its self-compacting property where no compaction is required the concrete flows from the pump to fill the mold. With this property, it can be pumped for long-distance and height.

The specially engineered concrete is also known as foam cement, foamed concrete or lightweight flow-able fill.

Which types of material used in Cellular Concrete?

Cement

The cellular lightweight concrete is a homogeneous combination of Portland cement, cement-silica, cement-pozzolana, lime-pozzolana; lime-silica pastes with having of identical cell structure obtained from gas-forming chemicals or foaming agents at measured levels.

Fly Ash

Fly ash is a by-product of thermal powerplant and its disposal be very expensive. The fly ash is used in the manufacturing of light-weight concrete. fly ash is a key ingredient and at the same time, the disposal problem is also solved.

Foam

In the raw material the foam is used and in the making of cellular concrete is Genfil and its organic substance. The size of the bubbles has differed from o.1 to 1.5 mm in diameter. The foam generator is used to make stable foam using an appropriate agent.

Reference codes of Cellular Concrete

ASTM C 869 – standard specification for Foaming Agents Used in Making Preformed Foam for Cellular Concrete.

The ASTM C 796 – standard test method for foaming agents for use in producing cellular concrete using preformed foam.

ASTM C 495 – standard test method for compressive strength of lightweight insulating concrete.

Types of Cellular Concrete (Density vise)

The cellular concrete is divided into 3 types based on density.

High-Density Cellular Concrete

This is a structural grade concrete having a density of 1200 k/m³ to 1800 kg/m³ and it is used in the construction of load-bearing walls, partition walls and in the production of pre-cast blocks for load-bearing brickwork.

Medium Density Cellular Concrete

The density range is 800-1000 kg/m³. It is mainly used in the manufacturing of pre-cast blocks for non-load-bearing brickwork.

Light Density Cellular Concrete

Light density cellular concrete has a density range of 4—600 kg/m³. The LDCC is ideal for thermal and sound insulations. It is mostly fired resistance, termite and moisture absorbent. It is also used instead of glass wool, wool wool, and thermocol.

Advantage of Cellular Concrete

Lightweight

Having the lightweight is advantageous for building dead loads and craning works.

Fire Resistance

The air pocket in the concrete works as a barrier for fire. The structure made with cellular concrete is non-combustible and can endure fire breakout for hours.

Thermal Insulation

Cellular concrete is a perfect thermal insulator.

Acoustical Insulation

The low density increases acoustical insulation.

Environment-Friendly

Fly-ash based CLC is suitable to use as the fly-ash is the by-product of the thermal power plant.

Cost-Efficient

The cost of the raw material is used in the concrete is decreased as the foam is used in the concrete. The use of waste of thermal plant-like fly ash saves money invested for cement products.

Other Advantage

The cellular light-weight concrete is termite-proof and resistant to freezing issues.

Where are the Cellular Concrete is used?

• The cellular lightweight concrete is used as thermal insulation in the form of bricks and blocks over flat roofs or non-loading walls.
• Bulk filling by applying relatively low strength material for old sewer pipes, wells, unused cellars and basements, storage tanks, tunnels, and subways.
• Production for heat-insulated light wall panel.
• Maintain an Acoustical balance of concrete.
• Manufacture cement and plaster-based light plate.
• For the production of special light heat-resistant ceramic tiles.
• For the soil water drainage purposes.
• Used in the bridge to prevent freezing.
• Used in tunnels and shaft filling and lightweight concrete manufacturing.
• Production in Perlite plaster and Perlite lightweight concrete.

Normal Concrete vs High-Strength Concrete Properties and Differences

Concrete is used as construction material and it is categorized as normal concrete or high strength concrete based on its compressive strength. The compressive strength of normal concrete is between 20 and 40 MPa. The strength of high strength concrete is above 40 MPa.

The high strength concrete has compressive strength between 40 and 140 MPa which is discussed in this article.

As time goes the difference between normal and high strength concrete also changes. 100 years ago the concrete having a compressive strength of 28 MPa was considered as high strength concrete. Now the concrete can get strength greater than 800 MPa and is called reactive powder concrete.

When we talk about the application the normal strength concrete is widely used compared to high strength concrete. The main benefit of high strength concrete is for reducing weight, creep or the permeability issues, for improving the durability of the structure and for special architectural requirements were elements carry smaller loads.

What are the properties of Normal and High Strength Concrete?

Whether it is normal or high strength concrete, it should be mixed having the nature of plastic or semi-fluid that it can mold by hand or by using mechanically.

It is very important that the mixture does not go through bleeding or segregation in handling or transportation. The uniform distribution of aggregates helps the concrete to control the segregation.

Workability factors of Normal and High strength Concrete

The workability factor is the ease where the concrete is placed, compact and finished in its fresh state.

The normal strength concrete possesses having good workability that all concrete ingredients are in proper and accurate proportions. These aggregates must be of a proper gradation.

The high strength concrete mix is often sticky and also found difficult to be handled and placed. This is even if the plasticizes are used. It is due to high cement content in it.

Bleeding Factors for Normal and High Strength Concrete

The bleeding is the settlement of solid particles of cement and the aggregate in the fresh concrete mix which results in the development of a layer of water on the top of the concrete surface. The smaller bleeding does not make any issue but the large-scale bleeding affects the durability and strength of the concrete.

When we compared the normal and hard strength concrete the high strength concrete does not bleed. Which is because the high strength concrete has smaller water content and a high amount of cementitious materials. The air-entrained concrete also has fewer chances to bleed.

Permeability of Normal and High Strength Concrete

The durability problems like corrosion resistance, chemical and creep have a direct relationship with the permeability of the concrete. If the foreign substance enters inside the concrete the damage occurs. It depends on the permeability property and the paste and aggregates present in the concrete.

The decrease in permeability beneficial in

• Improves sulfate and chemical attack resistance
• Resistance to corrosion
• Resistance to chloride penetration

The below table shows the test results of various permeability tests conducted on the different concrete mixes. The table also provides information on normal strength concrete and high strength concrete in water and cement ratio.

The lower water-cement ratio with an adequate curing period helps in having a concrete of lower permeability. For the normal strength concrete, the permeability is found to be in the range of 1 x 10 ^-10 cm/sec.

The additional cementitious materials added in the concrete mix like silica fume, fly ash and GGBFS helps to reduce the permeability of the concrete.

High strength concrete has a lower value of permeability compared to normal strength concrete. which is because the high-strength concrete is designed with a lower water-cement ratio. The silica fume is commonly used in the mix. The high strength concrete has permeability ranges from 1 x 10 ^-11 to 1 x 10^-13 cm/sec.

The high strength concrete has low permeability and high resistance to chloride attack which makes it suitable for bridge construction, parking decks and structures are exposed to seawater.

Carbonation of Normal Strength Concrete and High Strength Concrete

The carbonation happens on the surface of the concrete. the carbonation is related to the permeability of the concrete. carbon dioxide of the air reacts with the compounds present in hardened cement paste. This reaction is called calcium carbonates.

The effect of carbonation is mentioned in the permeability factor is less in high strength concrete compared with normal strength concrete.

In both types of concrete mix, the essential amount of protective concrete covers the reinforcement steel which reduces the easy reach to the reinforcement.

Difference between Normal Strength Concrete and High Strength Concrete

The normal strength at 40% of compressive strength value the micro-cracks are formed. These interconnects and propagates reaches 80 to 90% of the strength.

In the normal strength concrete, the fracture surface is very rough. This zone is formed along with the transition zone between the paste matrix and aggregates. The fracture surface in high strength concrete is smooth.

Effects of the Fly Ash on Durability of Concrete

Fly Ash is used as an admixture in concrete. The durability of the concrete with fly ash is discussed here.

The use of concrete in aggressive environmental conditions has been increased substantially. Concrete structures are used to provide support for types of machinery, staff, and products of oil and gas exploration and production.

The concrete structures are used in a nuclear reactor to keep the gases and vapors which released at high temperature and pressure in emergency situations. The fly ash plays an important role.

Effects of Fly Ash on Durability of Concrete

It has effects like

• Permeability of Concrete
• Carbonation of Concrete
• The durability of concrete subjected to repeated cycles of freezing and thawing
• Abrasion and erosion of fly ash concrete
• Sulfate resistance of concrete
• Alkali aggregate reactions in concrete
• Corrosion of steel reinforcement in concrete
• Concrete exposed to seawater

Effect of Fly Ash on Concrete permeability

The permeability of concrete is based on the quantity of hydrated cementitious material at any given time. It is said that the permeability of fly ash was lower than the permeability of controlled concrete after 28 days of curing.

On the other side after six months the fly ash concrete is more impermeable and also achieves substantial imperviousness. The above difference is because of the pozzolanic activity of fly ash and the pozzolanic reaction is low at the beginning.

This is how the fly ash could produce better concrete durability.

Fly ash effect on Carbonation of Concrete

The carbonation is where the carbon dioxide in the air which reacts with calcium hydroxide, calcium silicate and aluminates in hydrates cement and make calcium carbonate.

This process took place in mostly moist situations and the rate of the carbonation of concrete is specified by concrete permeability, saturation degree, and quantity of calcium hydroxide which is ready for the reaction.

The carbonation is the main reason for the steel corrosion resistance. The main focus should be on proportions of concrete mixture, concrete cover and the period of moist curing when a high amount of fly ash is used.

The effect of fly ash on the durability of the concrete with repeated cycles of freezing and thawing

If the concrete is made with exact proportions it has become frost resistance. The fly ash may lead to an increase the number of admixtures that are necessary to obtain the particular level of entrained air and it is also influenced by entrained air stability in fresh concrete.

The research is carried on the effect of the fly ash on the durability of concrete for repeated cycles of freezing and thawing and supports the statement by Larson that Fly ash has no apparent ill effects on the air voids in hardened concrete.

When the proper volume of air is entrained the characteristics of the void system meet the criteria.

Abrasion and Erosion of Fly Ash Concrete

There are many situations where concrete is used for scraping, attrition, sliding of cars, ice, and other items. It has been said that the concrete resistance against abrasion is proportional to its compressive strength.

The low abrasion resistant fly ash concrete might expect unless the concrete is adequately and thoroughly curried. It is proved that concrete with ASTM class F fly ash provider for better abrasion resistance than the ASTM class C or with no fly ash content.

The concrete is eroded when the water flows over the surfaces. With the fixed slump value, the concrete resistance against erosion can be increased by increasing the strength and cement content.

Fly Ash effect on Sulfate Resistance of Concrete

It is proven in research carried out by Dikeou that sulfate resistance of concrete can be improved by using fly ash.

The effect of fly ash on alkali-aggregate reactions on concrete

It is proven that fly ash is very effective in decreasing the detrimental effect of alkali-aggregate reactions (AARs). This effect is only decreased where the siliceous aggregates are involved.

The alkali-aggregate carbonation is one type of AAR that is less responding to fly ash inclusion. But the expansion of alkali-aggregate can be decreased with low calcium fly ash replaces the 25-30 percent and under the condition that alkali is less than four percent.

Effect of the fly ash on the corrosion of steel reinforcement in concrete

There is always a concern of corrosion of steel reinforcement in fly ash concrete. This is happened because of chloride ions from the seawater or de-icing. It has happened when the carbonation depth in concrete reaches the steel reinforcement and if the oxygen and moisture are reached to the surface of the reinforcement the steel bar will corrode.

It will be protected from corrosion if the fly ash concrete cover is sufficient.

Fly Ash effect on concrete exposed to seawater

The concrete used in marine has a danger of wetting and dying, waves, abrasion by debris and sand, freezing and thawing cycles and reinforcement corrosion which are occurred in a chemical medium.

But the entirely submerged concrete is less affected by the above factor. If the fly ash concrete has 25 percent replacement by mass and it is under the condition of water to cementitious materials less than 0.50 have a good performance under freezing and thawing and wetting and drying conditions.