Construction of house needs different materials and hence needs study. The general guide points have been discussed by us in Material Buying Guide In General. Here we discuss buying guide for steel.
One need to do adequate research when you plan to buy steel bars. The steel bars are important for the life of the structural system. They are known as rebars in short form. They are also known as reinforcing bar or reinforcement steel.
Steel bars and cement are the most important materials used in the building. The strength of building is directly related to the strength of steel bars. We already discussed the cement buying guide in our recent content.
Goto Xingtai Steel to know more.
There are two types of steel bars in the market.
Mild steel bars are plain in surface and are round sections of diameter from 6 to 50 mm. They can be manufactured in long length and can be cut quickly and bend easily without damage.
Mild steel bars are available in Fe410-S (Grade 60) or Fe410-O (Grade 40).
Medium tensile steel bars are available in Fe540 (Grade 75)
High strength deformed steel bars are provided with lugs, ribs or deformation on the surface of the bar to improve the bond with the concrete. They are also twisted to improve the bond with the concrete.
Cold twisted deformed bars (Ribbed or Tor Steel Bars) are recommended as best quality steel bars for construction work.
They are available in Grade Fe415, Fe415D, Fe500, Fe500D, Fe550, Fe550D, and Fe600.
Fe indicates the specified 0.2 percent proof stress or yield stress in Newton per square millimeter.
You will have to spend a lot of time towards reviewing types, brands and its grade while buying.
Steel bars are needed as reinforcement in RCC structure. Concrete is the materials that is very weak in tension but strong in compression. To compensate for this imbalance of concrete, we provide steel bars in concrete to increase its tensile strength.
You therefore have to select the right type and grade of steel bars depending on your requirement or as considered in structural design/structural drawing by the structural engineer.
First you have to decide why and where do you need steel? i.e. for foundation, slab, and beam, column or for water tank and where is your area located? I.e. near the sea shore is It in corrosion prone area? You may than need CRS steel.
You can check the quality of steel bars by following steps
Check the percentage of deviation (Rolling Margin) in weight of reinforcement steel.
Rolling margin is very important when you buy in tonnes, and you get paid in lengths.
Avoid using steel from those rolling mills which use “rerolled or scrap steel” as a row material. These are likely to have higher carbon content, which are prone to high corrosion.
b) Always ask for “chemical composition” test from the supplier. Apart from other material, the content of carbon is very important. It should not be more that 0.25 percent as it would accelerate corrosion and which will not only reduce the life of building but also will increase periodical repairing work.
Normally in advanced countries, people don’t buy steel, but they buy “Readymade cut bars” as per designed length and shape i.e. as per bar bending schedule.
They have to be simply placed in position. But here also you need to exercise many of the above points.
When you buy “Readymade Cut bars”, check the following
(i) Check the shape and length of each type of bar as per bar bending schedule.
(ii) Check nos and stack each bar separately.
(iii) Always check the hooks, its shape and length.
(iv) Check the quantity.
Check whether the steel bars you buy bears a national certification like ASTM A706, JIS G, BS, ASTM A615, JIS G and IS 432 (Mild Steel Bar), IS (High Strength Deformed Steel Bar) etc. The certification assures you about its quality as well as the reputation of the manufacturer.
When you buy steel bars, you should read all the technical specifications which are either described in the product literature or on the manufacturer’s website. We have to check whether the product specification represented by sales persons and the literature confirms or not. Try to understand and follow all the cautions of use and advice for use, etc. as per the written specifications in the literature. It is also necessary to read the terms and condition of warranty, guarantee, etc.
You may economise and save on each and every individual item, but you should not save on steel bars. They are the definite requirement of your house and directly related to safety and stability of your house.
It is advisable to provide steel bars as specified in drawing or as instructed by the structural consultant. Some people avoid consulting the structural consultant and providing the steel as per thumb rule to save the fees of the structural consultant. They forgot that every structure has carried different behaviour and one cannot use the same thumb rule for different structures. Do not get away by idiotic thumb rule of using this 2 to 3 kg of steel per Sq.ft. One thing we can tell you that thumb rules will raise your budget in future as they ultimately increase the cost of repairing work. They either excess your budget by over design or reduce the lifespan of the structure by under design.
You should also estimate the exact quantity of steel diameter wise. The wastage of steel bars will cost you high. You need to work out quantity in advance so you can bargain with the supplier or distributor.
You must search for the right supplier or distributor and their location. You should also find out whether it is directly available from the manufacturers or distributors or retailers etc. The price will definitely depend on from whom you buy the steel bars.
The cost of transportation, taxes and duties including the cost of loading and unloading at the site are the necessary point to remember as they also affect your budget while buying steel bars. Steel being heavy material, they form substantial weight and hence higher cost of the transportation.
Always use the popular brand of steel bars as they may have a certain quality. It is advisable to use the brand suggested by your structural consultant or use the government-approved brand or ISI brand.
The Price of steel bars vary between Rs 30 to Rs 60 per kg. Kamdhenu, Thermax, Tata Tiscon, Jindal, Essar, Vizag and Electro are the popular brands of steel bars in India who make different types of steel with different grade.
Always try to learn how to test the materials on site as well as in laboratory in case of bulk buying.
Study the above factors of steel bars and then select the right material and the supplier.
If you want to learn more, please visit our website astm a615 rebar.
It is advisable to place written order if you are buying the large quantity. It should include specifications of steel bars, rates including taxes, transportation, and loading-unloading charges, etc. It should also include quantity, time of delivery, warranty, guarantee, terms of payment including advance.
When you receive steel bars at the site, please check the make, quantity and quality. Also check ISI marks, brand and whether there are any damages to the steel bars.
Also check the weight of steel bar received on site by at approved weighbridge.
Use this formula for the actual weight of steel (site) = Total weight of truck with steel bars – The empty weight of truck (Weight without steel).
Do not stack directly on the ground as the ground moisture will rust it. Store the steel bars in godown and place wooden batten below them so they should not directly rest on ground.
If you are satisfied with the quality and quantity of the steel bars, then make payment as per the contract and obtain the receipt of payment. Preserve all the bills, product literature and the warrant/guarantee certificate, etc.
The steel bars are generally one-time purchase, and it has a long lasting service life when embedded in concrete. If we leave them in open environment, they get corroded fast. Hence try to use them as early as possible or store steel bars in warehouse.
You can buy steel bars in 8 mm (18 nos per bundle), 10 mm (12 nos per bundle), 12 mm (8 nos per bundle), and 16 mm (5 nos per bundle) sizes. They are commonly used for house construction. You can also buy steel bars with the bigger diameter of 20 mm (3 nos per bundle), 25 mm, 28 mm, and 32 mm, which are used for high-rise buildings only. They are generally packed in the bundle, and above 20 mm diameter, they are available in the single piece.
The standard length of steel bars is 12 meter, but you can select the length as per your requirement.
Nowadays Thermo Mechanically Treated (TMT) steel and Corrosion Resistance Steel (CRS) are also used in Reinforced Concrete Framed Structure construction. They have good elongation, bending strength, ductility and high tensile strength and high corrosion resistance.
In the world of construction, steel rebar is the unsung hero that gives concrete structures their strength and durability. Whether you’re building a simple driveway or a multi-story building, choosing the right rebar is crucial for structural integrity. Let’s explore the essential aspects of steel rebar sizes and grades to help you make informed decisions when buying steel products for your next construction project.
Steel reinforcement bars, commonly known as rebar, are embedded in concrete to increase its tensile strength. Concrete excels at handling compression forces but needs reinforcement to withstand tension and bending. This is where rebar comes into play, creating a composite material that can handle both types of forces effectively.
Rebar sizes are standardized and identified by numbers that correlate to their diameter. The size designation (#3, #4, etc.) roughly corresponds to the bar’s diameter in eighths of an inch. Here’s a breakdown of common rebar sizes and their typical applications:
The size you choose directly impacts the reinforcement’s weight, strength, and cost. Selecting the appropriate size ensures structural integrity without unnecessary expense.
While size refers to the physical dimensions, rebar grade indicates its strength properties. The grade number represents the minimum yield strength in pounds per square inch (PSI). This is the point at which the steel begins to deform permanently under stress.
Beyond sizes and grades, rebar comes in different types based on its coating or composition:
The most common type, made from carbon steel and often featuring ribs or deformations that enhance bonding with concrete.
Coated with zinc through hot-dip galvanizing, this rebar offers superior corrosion resistance—up to 40 times more resistant than traditional steel. It’s particularly valuable in marine environments or where exposure to de-icing salts is expected.
Features a protective epoxy coating that prevents corrosion, extending the lifespan of structures exposed to corrosive elements.
Though more expensive, stainless steel rebar provides exceptional corrosion resistance without coating, making it ideal for critical structures in harsh environments.
Non-metallic, non-corrosive, and non-magnetic, fiberglass rebar works well in specialized applications where steel might be problematic, such as MRI facilities or highly corrosive environments.
Quality matters tremendously when it comes to rebar. Look for products that meet established standards:
Selecting the appropriate rebar involves considering several factors:
Understanding steel rebar sizes and grades is essential for ensuring the structural integrity of concrete constructions. By selecting the right combination of size, grade, and type, you can achieve optimal strength, durability, and cost-efficiency in your projects. Whether you’re working on a residential driveway or a commercial high-rise, the proper rebar selection lays the foundation for successful construction.
For more information, please visit concrete slab mesh.