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Fly ash is the fine ash collected from the flue gas after coal combustion, and it is also the main solid waste discharged from coal-fired power plants. Its main components are oxides of silicon, aluminum, iron, calcium, and magnesium. With the development of the power industry, the discharge of fly ash from coal-fired power plants is increasing year by year. If a large amount of fly ash is not treated, it will generate dust and pollute the atmosphere. But now, fly ash can also be used as a resource. The properties of fly ash Appearance: The appearance of fly ash is similar to cement, and the color is between milky white and gray black. The color of fly ash is an important quality index, which can reflect the amount of carbon content, and to a certain extent, the fineness of fly ash. The darker the color, the finer the particle size of the fly ash and the higher the carbon content. Classification: Fly ash can be divided into low calcium fly ash and high calcium fly ash. Generally, the color of high-calcium fly ash is reddish, and the color of low-calcium fly ash is gray. Fly ash particles are porous honeycomb structure with large specific surface area and high adsorption performance. Particle gradation: The gradation of fly ash can be roughly divided into three forms. The first is fine gray. The particle gradation of fine ash is finer than that of cement, and it is mainly used to replace cement or cement mixture in reinforced concrete. The second type is coarse ash. The particle gradation of coarse ash is coarser than that of cement, and it is mainly used in building materials such as mortar to replace aggregates. The third is mixed ash. Fly ash mixed with furnace bottom ash can be used as aggregate substitute or for filling. Density: The density of ordinary fly ash is 1.8-2.3g/cm3, which is about two-thirds of Portland cement. The variation range of the bulk density of fly ash is 0.6-0.9g/cm3, and the bulk density after vibration is 1.0-1.3g/cm3. The density of high calcium fly ash is slightly higher. How is fly ash produced? The combustion process of fly ash is as follows: The pulverized coal burns in a suspended state in the furnace. Most of the combustibles in the coal burning process can be burned in the furnace, while a large amount of non-combustibles in the pulverized coal are mixed in the high-temperature flue gas. These incombustibles (mainly ash) are partially melted due to high temperature. At the same time, due to the effect of its surface tension, a large number of fine spherical particles are formed. Under the action of the induced draft fan at the tail of the boiler, the flue gas containing a large amount of ash flows to the tail of the furnace. As the flue gas temperature decreases, a part of the molten fine particles will be in a glassy state due to a certain degree of rapid cooling, thus having a higher potential activity. Before the induced draft fan discharges the flue gas into the atmosphere, the above-mentioned fine spherical particles are separated and collected by the dust collector, which is fly ash. Advantages and disadvantages of fly ash Advantages 1.Energy saving and emission reduction. The recycling of fly ash can effectively realize the reuse of resources and avoid the waste of resources. At the same time, by reducing the demand for raw materials, it also reduces pollution such as waste gas and waste water produced during mining and other production processes. Therefore, the use of fly ash can have the effect of energy saving and emission reduction. 2.Reduce costs. Fly ash can replace part of cement as a relatively cheap cement admixture, thereby reducing the cost of building materials. During use, fly ash can also reduce the slurrying time and cement content of concrete, and improve the construction speed and quality of concrete engineering. 3.Improve the environment. Fly ash is a very stable material that will not decompose or decay over time. At the same time, due to the relatively light weight of fly ash itself, its transportation and storage are also relatively convenient. All these factors can make fly ash easy to recycle and cause less environmental pollution. 4.Improve the performance of existing materials. As an admixture of concrete, fly ash can improve the durability, frost resistance, compressive strength and other characteristics of concrete. These characteristics are difficult to achieve with traditional concrete. Therefore, the addition of fly ash can not only save resources, but also improve the performance of concrete, which is of great help to practical applications. 5.Expand new markets. Recycling of fly ash can open up new markets. In some regions, such as Europe, America and Asia, fly ash has become one of the widely used construction materials. With the improvement of national requirements for environmental protection and energy efficiency, fly ash will receive more and more attention. Disadvantages 1.Need to master the appropriate proportion. When fly ash is used as a raw material, the ratio of concrete to fly ash must be strictly controlled so as not to affect the quality of concrete. 2.Not suitable for all types of concrete. While fly ash can improve the performance of concrete, it is not suitable for all types of concrete. Need to pay attention to strict distinction when using. 3.It is more difficult to assess the quality. If too much fly ash is mixed into the concrete, it may cause problems such as a decrease in the strength of the concrete. However, it is difficult to evaluate the amount of fly ash, so it must be used with caution, otherwise it may affect the quality of concrete. Uses of fly ash Fly ash is rich in resources, low in price, and contains a large amount of active ingredients. After processing, it can be used for secondary use in the fields of building materials, concrete, and chemicals. 1.Make concrete and cement. After sorting and grinding, the fly ash can be used as a partial substitute for

The word “cement” is derived from the Latin word “caementum”, which means chipped rock fragments. Limestone is well known to be the oldest material to be used as a binder. Lime was produced by heating near pure limestone, and lime mortar was created by adding and mixing water and sand. Concrete was first used in the Roman Empire. The concrete used in the construction of the “Castel Sant’Angelo” in Rome, constructed in 138 BC, has preserved its characteristics, while the stone has suffered from erosion. Binders of different types were used for the Egyptian Pyramids, the Great Wall of China, and castles constructed in different periods by many different civilizations. The ancient Greeks mixed volcanic tuff from the island of Santorini with lime to obtain mortar, or used a clayey limestone to produce a kind of hydraulic lime that was used for the production of mortar. In Egypt, impure calcinated gypsum was used rather than cement. Almost 2000 years ago, the Greeks and Romans ground lime and “pozzolin” – a volcanic ash that is these days known as “pozzolana” – and used the mixture as mortar in masonry with the addition of sand. Although various binders were used in ancient times, studies of ancient construction methods have been unable to garner much information on how these binders were obtained, or the working conditions. For example, Roman philosopher Gaius Plinius wrote, “… it is beyond understanding how lime burns when it comes in contact with water, after having previously been obtained by burning with fire”. The use of cement in Roman architecture started with the Colosseum and the Roman Baths in 27 BC. The Romans mixed ground volcanic ash with lime to produce cement, and after observing that cement can set underwater, cement started to be used in the construction of ports. This mixture would later be named “Pozzolanic Cement” after the village of Pozzuoli in Vesuvius, near Rome.   A sample of Roman Architecture.   In England, volcanic ash was ground and used in the manufacture of bricks and roof tiles. Large Medieval cathedrals such as those of Chartres and Rheims in France, and those in Durham, Lincoln and Rochester in England, were constructed using what were advanced technologies at the time. The Romans were unaware of the technologies being used 1,000 years earlier. Most probably, the Romans identified the characteristic features of volcanic ash, and used it in their buildings for various purposes. Marcus Vitruvius Pollio, a Roman architect and engineer who lived in 1 AD, detailed structures and related technologies from the past in his book “Ten Books of Architecture”, and recommended concrete for its ability to give “polish to the floor and to create a strong foundation”. The book also mentioned the use of mixed lime and crushed rock, pozzolan, for the reinforcement of buildings, which is also said to preserve its hardness underwater. European societies lagged behind the Romans. Mortars were prepared especially using lime, and setting took a reasonably long period of time. The use of pozzolan for the preparation of mortar was rediscovered by the Europeans in the Middle Ages.   Aqueduct, Segovia – Spain   In 1756, John Smeaton, who was given the responsibility for the construction of Eddystone Lighthouse, studied the chemical features of lime, and reached significant conclusions on its binding qualities. Later, in the light of these studies, Joseph Parker produced a binder known as “Roman Cement”, for which raw material was obtained from the limestone around London, and the produced binder was used in the construction of canals and ports. The “English Cement” produced by James Frost in the same era was not as popular as Roman Cement. The Renaissance ushered in a new era in which people were encouraged to think in different ways, and the doors of the industrial revolution were thrown wide-opened. The naval fleet of England, comprising ships for trade and exploitation, required new lighthouses in the 18th century, and this became a driving force for the cement industries. Eddystone Cliff near the Port of Plymouth in England had long posed a threat to the constant flow of vessels entering and exiting the port. Using mortars that hardened underwater, with a view to providing convenience to sailors, the construction of the 37-m high Eddystone Lighthouse was completed between 1757 and 1759, built from a mixture of lime, water, clay and iron cinder. The lighthouse was fixed to iron rods embedded in holes in the sea floor and secured with lead. In 1756, English engineer John Smeaton determined that the best cement was based on soft limestone with a certain amount of clay content. Almost 40 years later, James Parker produced cement in England using limestone with a high impurity ratio. The production of cement out of clay and limestone was initiated in France in 1813 by Louis Vicat, and in England in 1822 by James Frost. The binder produced by Louis Vicat went on to be used in bridges and concrete canals. Vicat studied the feature of under-water setting of the hydraulic cement, the binders that were obtained by mixing the lime and the pozzolan, and the natural cement. He produced a synthetic binder by mixing silica, aluminum and lime at certain amounts. His studies, experiments shed a light on production of Portland Cement that is widely used today. Vicat used his hydraulic binder in one of the abutments of the Souillac Bridge, the construction of which was completed in 1822. In 1824, Joseph Aspdin, a mason from Leeds, heated ground clay and limestone until the limestone calcified, and then ground the mixture once again, observing that the mixture set some time later after adding water. Aspdin named his creation “Portland Cement”, due to its resemblance to the rock extracted from quarries on the “Isle of Portland on the British Coast”, and its use became widespread in the construction of buildings in England.   Joseph Aspdin, 1824   The “Wakefield Arms” building, which is still standing next to Kirkgate Station in England, is known

The development of road traffic directly affects the development of the national economy and the improvement of people’s living standards. Today, the world’s roads mainly include asphalt roads and concrete roads. So, what are the advantages and disadvantages of these two road surfaces? What kind of road surface should we choose under different conditions? Asphalt road Advantages Strong adaptability. Asphalt road is a flexible pavement, and the flexible pavement has a strong adaptability to the uneven settlement and deformation of the foundation and subgrade. Concrete roads have higher requirements for foundations and subgrades. High comfort. The asphalt road is relatively soft. Due to the double shock absorption of the wheels and the road surface, the road surface vibration is small and the noise is low when driving, which makes the passengers feel very comfortable during driving. Low construction difficulty. When laying asphalt roads, a lot of professional equipment is required. Although the investment in equipment is high, the process is relatively simple and efficient. Simple maintenance. If a few kilometers of asphalt road is damaged and needs to be repaired, it only takes one night to complete it, and it can be opened to traffic as usual the next day. Poor road reflection. Asphalt road is a black pavement, which has poor reflection ability to light. On the highway, the asphalt pavement can effectively relieve the driver’s visual fatigue. Disadvantages Poor water resistance. A large amount of coarse aggregate and fine aggregate are used in the paving process of asphalt road, so that there are a lot of voids inside. If it is soaked in rain for a long time, it will cause the asphalt to lose its viscosity, causing the interior to loosen and damage the road surface. High maintenance cost. Although asphalt road is fast to repair, it is more expensive. Even if the repair section is short, a full set of equipment is required. Poor environmental protection. Asphalt pavement is a non-degradable material, which will pollute the surrounding land and groundwater during use. Moreover, some harmful gases will be produced during the heating and paving of asphalt, which will have a certain impact on the construction personnel and the surrounding air. High fuel consumption. The research shows that when the vehicle speed reaches 60km/h, the concrete road saves 8% of the fuel consumption compared with the asphalt road. When the vehicle speed reaches 120km/h, the fuel consumption can be saved by 15%. Concrete road Advantages Strong bearing capacity and good stability. Concrete pavement is a rigid pavement with high bearing capacity, and its edges are also very strong, not easy to be crushed, so it is not necessary to lay curbstones. Moreover, it will not change greatly due to sudden changes in temperature, and has good stability. Good durability. Due to the strong bearing capacity and good stability of the concrete road, it can be used as usual even if it is soaked in floods or exposed to the sun for a short period of time. It will not affect the pavement and will not soften the ruts like asphalt pavement. Long service life. Experiments have shown that the service life of concrete road is twice that of asphalt road. Abundant raw materials and high economic benefits. One of the main raw materials for concrete pavements is cement. Cement has the characteristics of large production, wide distribution, cheap and easy availability. So this makes the pavement construction cost low. Disadvantages Low comfort. Concrete road is a rigid pavement with a high modulus of rigidity. The noise is slightly louder, and the shock absorption ability is poor, which affects the comfort of the road surface. Difficult to maintain. When the concrete pavement is damaged, the whole concrete slab needs to be broken and cleaned, rather than just repairing the damaged pavement like the asphalt pavement. Too many seams. Concrete pavements are constructed with a large number of seams. These seams will not only increase the difficulty of road construction and maintenance, but also easily affect the comfort of driving. White pavement is highly reflective. Although white roads are good for driving at night, they are highly reflective during the day and can easily cause eye fatigue. Therefore, asphalt roads are often used on highways in many places. How are asphalt vs concrete roads made? Let’s take a look at the production process of asphalt road and concrete road. Construction technology of asphalt road First of all, bitumen, aggregate, mineral powder, water, etc. are used as raw materials, and the asphalt mixture is produced in batches by using an asphalt mixing plant. Next, the finished asphalt mixture is transported to the construction site by dump truck. The finished asphalt transported to the site needs to be used in time. If the temperature of the asphalt mixture is not up to the required temperature, or if the asphalt mixture has condensed into lumps, it should not be used. The asphalt concrete paver then begins to pave the asphalt slowly, evenly and continuously. After paving, the paved asphalt is rolled by the road roller. The rolling should not be less than 2 times until there are no obvious rolling trace. Finally, when the temperature of the pavement naturally drops below 50°C, the asphalt pavement can be put into use. If you need to start opening to traffic in advance, you can sprinkle water to cool down and reduce the road surface temperature. Construction technology of concrete road First of all, the raw materials for the production of concrete mainly include cement, aggregate, additives, water, etc. The strength of concrete required for different road grades is also different. Therefore, it is necessary to determine the proportion of concrete first, and then use concrete mixing equipment to produce concrete according to different proportions. The concrete mixer truck then transports the finished concrete to the construction site. It needs to be poured immediately after being transported to the site. When pouring, the material should be unloaded evenly, and the speed of material distribution should be adapted to the speed of paving. Finally, the concrete pavement should be maintained immediately

Steel bars are an integral element of the construction industry. They serve as crucial reinforcements for concrete structures. Possessing the high tensile strength of steel, these bars are capable of withstanding heavy loads. As a result, engineers and architects use them in the construction of buildings and bridges to ensure their strength and durability. Table of Content 1. Different Sizes of TMT Steel Bars 2. Steel Weight per Bundle 3. How Many Steel Bars Are There in One Bundle? The most common type of steel bars are the TMT bars, which are highly durable and provide immense strength to a structure, enhancing longevity. The reliability of architecture and construction on these bars is not a new topic to discuss. However, today, Sree Metaliks Ltd. has come up with something entirely different. We are here with this blog post to help you know how to buy steel bars. This post will answer one of the most common questions among engineers and architects- how many steel bars in one bundle? So, start reading below. Different Sizes of TMT Steel Bars Before finding out how many steel bars in one bundle, let us start with the basics first and understand what are the different sizes of TMT Steel bars. Understanding the different sizes is crucial because as the size of the steel bar increases, the number of bars in a bundle decreases. 8mm TMT Bars These bars are widely used in light construction. These are most suitable for small structures as they have low load-bearing capacity. 10mm TMT Bars Steel TMT bars are also available in 10mm size. These are medium sized bars and are usually used in residential as well as commercial construction. 12mm TMT Bars The enhanced strength of these bars makes them suitable for reinforced concrete structures. As a result, they are used in large-sized projects. 16mm TMT Bars If you are looking for TMT bars for heavy-duty construction, pick 16mm TMT bars. They are generally used for industrial structures, high-rise buildings and bridges. 20mm TMT Bars Another TMT bar size is 20mm. These are suitable for large-scale projects as they offer robust support for heavy load-bearing structures. 25mm TMT Bars These are used in large-scale infrastructure projects for their high load-bearing capacity and strength. 32mm TMT Bars Industrial structures, large bridges, high-rise buildings and other high-load-bearing structures use these heavy-duty bars. Steel Weight per Bundle When buying TMT Steel bars, it is important to know about steel weight per bundle. Below is a table that will help you learn about this. TMT Steel Bar Size Length of TMT Steel Bar TMT Steel Bar Weight per Bundle 8 mm 12 m 45 Kg 10 mm 12 m 48.72 Kg 12 mm 12 m 51 Kg 16 mm 12 m 54.36 Kg 20 mm 12 m 57.6 Kg 25 mm 12 m 45 Kg 32 mm 12 m 74.21 Kg With a brief understanding of the sizes of steel bars and the weight of a bundle of different bar sizes, move on to the final section of this blog, which will introduce you to how many steel bars in one bundle. How Many Steel Bars Are There in One Bundle? Unlike earlier, manufacturers have now standardised the number of bars in a bundle to help engineers and architects plan without any confusion. The number of bars in a bundle varies with the size of the TMT bar. Below is a detailed explanation for each bar size. 8mm TMT Bars Let’s start with the smallest size and see how many rods in 8mm bundle are present. Used for light construction, these bars are the smallest in size. However, even with their small size, they offer versatility and appreciable strength. On one bundle of 8mm TMT Bars, 10 to 12 bars are present. 10mm TMT Bars Next are the 10mm TMT bars. So, how many bars in 10mm steel bundle are present? Not sure? These bar bundles have around 7 to 9 bars each. The 10 mm TMT bars are used in a wide range of projects due to their commendable strength and versatility. 12mm TMT Bars Moving forward in this list come the 12mm bars. There are around 5 to 7 12mm rod in one bundle of these bars. The diameter of these bars is slightly lighter than those mentioned above. As a result, they offer additional load-bearing capacity. 16mm TMT Bars The 16mm TMT bars are thick as a result the number of rods in their bundle further decreases. These bars are used for heavy duty construction projects like high-rise buildings, bridges and industrial structures. So, 16mm TMT bars’ 1 bundle how many pieces? It has only 3 bars per bundle. 20mm TMT Bars These are the standard-size bundles, appreciated for their substantial diameter. 20mm TMT bars are typically used for their heavy load-bearing capacity. As a result, they are used in large-scale construction of robust structures. One bundle of these bars has 3 bars. 25mm TMT Bars Moving to another big size of TMT bars, the number of bars decreases per bundle. Each bundle of 25mm TMT bars consists of only 1 bar. These are used for extensively robust structures. Large-scale projects make use of these TMT bars. 32mm TMT Bars Last comes the largest TMT bar size- 32 mm. Again, each bundle of these bars has only one bar. These are widely used in large-scale projects for their unparalleled strength and durability.

The architecture and construction industry has undergone significant changes in recent years and has been streamlined to accommodate sustainable building construction and maintenance, improved inventory, as well as efficient construction techniques. These changes are also reflected by the type of raw materials used for the different purposes and sustainably procured high-quality raw materials have grown popular in terms of their application and benefits. Table of Content 1. What Is Galvanized Steel? 2. Differences Between Regular And Galvanized Steel? 3. Advantages Of Using Galvanized Steel Over Regular Steel. One such raw material is galvanized steel, which has found fame as a better component as opposed to regular steel. Steel has always remained a staple in construction, and the introduction of galvanized steel has been proven to be a step towards sustainability and improved building integrity. As the construction industry continues to grow, it is important to understand what sets galvanized steel apart from regular steel. Galvanized steel as a construction raw material is not only stronger and more durable than regular steel, but it is cost-effective too. And this is not all. So, if you are interested to know more about this construction raw material and why it has gained such popularity across industries, here is a quick guide to what is galvanized steel, types of galvanizing, the differences between galvanized and regular steel, and what gives galvanized steel the edge over regular steel. What Is Galvanized Steel? While regular steel is abundantly available for construction, galvanized steel, as the name suggests, is a specially processed steel that undergoes the method of galvanization. So, what is galvanizing process? And how does this process turn regular steel into a better alternative? Let us find out! Galvanized steel is obtained by applying a coat of zinc over steel and iron as a means of protection against chemical hazards. The process of galvanization examples has become exceedingly popular as it substantially enhances the lifespan of steel, prevents physical damage, and protects against corrosive chemicals. This additional coating of zinc is responsible for making galvanized steel more corrosion-resistant, fire-resistant, and more durable. Additionally, high-grade galvanized steel is budget-friendly, and has wide application in the production of architecture and construction materials, as well as solar and automobile components. The types of galvanizing available at steel plants include thermal spraying, batch hot dip galvanizing, sherardizing, in-line galvanizing, sheet galvanizing and electroplating. Galvanized steel is usually obtained by following the simple steps as mentioned below: The industrially produced steel is first cleaned using a degreasing solution before it can be pickled. Once cleaned, the steel is pickled using diluted hot sulphuric acid to remove any chemical impurities that might be coating the steel. Before the steel can be coated with zinc, it must be fluxed into an aqueous solution containing zinc-ammonium chloride. Later, the steel is prepared for the galvanization examples process where it is immersed in molten zinc. Once processed in zinc, the freshly galvanized steel is prepared for inspection and the process of zinc-coating is repeated, if necessary. The galvanized steel is ready once the final product is up to the standards. Differences Between Regular And Galvanized Steel Galvanized steel has readily grown popular because of its enhanced capabilities, and is largely preferred to regular steel. So how different is galvanized steel from regular steel that makes it a better contender when it comes to construction? A. Industrial uses Steel is one of the most widely used industrial raw materials with a wide range of applications in construction, aerospace and automobiles. And although industrial steel is known for its toughness and strength, processed galvanized steel is substantially more durable and resistant to chemical and physical agents. Regular steel is durable against salt and water, but can corrode easily when exposed to chlorinated water. Galvanized steel, on the other hand, is coated with zinc, which is naturally resistant to corrosive chemicals, and is a popular building material in the construction of buildings, rail lines and bridges that require a resilient foundation. B. Temperature resistance Unlike regular steel which remains unchanged when in contact with heat, galvanized steel can lead to the production of toxic zinc fumes, making it unsuitable for the production of kitchen equipment and utensils. C. Cost Galvanized steel is significantly more lasting than regular steel, and can withstand damage for a longer period without the need for frequent maintenance. It is also relatively easier to produce without incurring additional charges, and therefore is cost-effective. D. Strength Galvanized steel has been recognized for its unmatched strength in industrial construction. And since the coating of zinc further reinstates the strength of galvanized material and steel pipes, it is considerably stronger than regular steel. The strength of galvanized steel is also dependent on the thickness of the zinc coating which makes it resistant to chemical corrosion and physical damage. Advantages Of Using Galvanized Steel Over Regular Steel While regular and galvanized steel have their unique properties that make them some of the most frequently used raw materials for industrial construction, galvanized steel has often been noted to have the edge over regular steel. So, mentioned below are some of the advantages of using galvanized steel that set it apart from regular steel: a) Longevity: Galvanized steel far succeeds regular steel in terms of longevity. Long-lasting and durable against most damages, steel pipes with a galvanized coating have an average life of 50 years, even when exposed to natural and urban hazards. b) Minimal first cost: Galvanized steel is preferred to regular steel by most firms as it has a lower first cost than other protective steel coatings, without compromising the integrity of steel pipes. Galvanized steel is also significantly more affordable in terms of application and labour costs. c) Protective coating: The protective coating in galvanized steel is significantly more durable, offering a higher resistance against mechanical damages caused during transport and construction. d) Lower maintenance: Not only is the process of galvanizing cheap, but it also helps in avoiding any additional costs incurred from frequent maintenance. The galvanized coating