Welded wire fabric is a type of material that consists of several parallel longitudinal wires that have been fused to cross wires using an electric fusion method. This results in an accurate spacing between the wires. The welding process is carried out by machinery, which ensures that the dimensions are precise. This method of production leads to significant savings in time, labor, and money.
Compared to other types of wire fabric, welded wire fabric is known for its high quality and consistency. This is because the electric fusion method used to produce it ensures that the wires are evenly spaced and properly aligned. Additionally, the use of machinery in the welding process eliminates the risk of human error, which can result in inconsistencies and defects.
Welded wire fabric is commonly used in construction projects. It can be used to reinforce concrete structures such as walls, slabs, and foundations. The precise spacing between the wires ensures that the concrete is evenly distributed, which makes the structure stronger and more durable. Additionally, the use of welded wire fabric can speed up the construction process, as it eliminates the need for manual labor to create a similar reinforcement structure.
The focus of this article is on welded wire fibre concrete, and we will discuss its general specification, advantages, uses, and comparison to other types of concrete. Welded wire fibre concrete is a popular choice in the construction industry due to its numerous benefits. It is a type of reinforced concrete that contains small, uniformly distributed fibers made of steel or other materials, which are welded together in a grid pattern.
One of the advantages of welded wire fibre concrete is that it has increased durability and strength compared to traditional concrete. The added fibers improve the tensile strength and toughness of the concrete, making it more resistant to cracking and damage from external forces.
Welded wire fibre concrete also has excellent resistance to shrinkage and cracking, which can be a problem with other types of concrete. This makes it a suitable option for areas with extreme temperature changes or where moisture levels vary significantly.
The uses of welded wire fibre concrete are diverse and can be found in many different construction projects. It is commonly used in the construction of bridges, tunnels, pavements, and other infrastructure projects that require high durability and strength. It is also used in residential and commercial construction for foundations, walls, and floors.
When compared to other types of concrete, welded wire fibre concrete has several advantages. It is more durable and resistant to cracking than traditional concrete and requires less maintenance over time. Additionally, it can be produced at a lower cost than other types of reinforced concrete, making it a cost-effective option for many construction projects.
In conclusion, welded wire fibre concrete is a popular and versatile option in the construction industry due to its increased strength, durability, and resistance to cracking. Its diverse uses and cost-effectiveness make it a desirable choice for many construction projects.
General Specification of Welded Wire Fibre Concrete
1. Material
Welded fiber wires are manufactured using materials that have high resistance to corrosion and can be used even in wet conditions. These materials include stainless steel rebar rods and galvanized steel rods.
To ensure the quality of the wires, they conform to the specifications of IS:432-Pt II/1982. According to these specifications, the wires must have an ultimate tensile strength of 570 N/mm2 and a characteristic strength of 480 N/mm2.
Overall, the use of high-quality materials and adherence to strict specifications ensures that the welded fiber wires are strong, durable, and suitable for use in various conditions.
2. Shape and Size
Welded wire fiber is commonly available in rectangle and square shapes. The fabric can be produced in widths up to 3000mm, but its length is limited by transportation considerations. When provided in a flat sheet form that is ready to be laid, the standard length is 5500mm. However, if the fabric is rolled, it can be supplied in standard lengths of 15m, 30m, or 45m.
The wires utilized for manufacturing the fabric typically range from 2mm to 12mm in diameter. The fabric is made in compliance with IS:1566-1982, and its long and cross-wire spacings can vary from 25mm to 400mm.
3. Cutting and Forming
Welded wire fabric is a material commonly used in construction projects. One advantage of this material is that it can be easily cut with wire cutters, making it a versatile option for various applications. This feature allows for precise sizing and shaping of the mesh, making it easier to fit into different spaces and structures.
When it comes to laying welded wire fabric in a staircase, this material is also quite adaptable. The mesh can be bent into the required size with relative ease, making it easier to work with when installing it in a stairwell. This flexibility means that contractors and builders can customize the mesh to fit the specific dimensions and design of the staircase, ensuring a perfect fit and maximum stability.
Overall, the ease of cutting and bending welded wire fabric makes it a popular choice for many construction projects. Its versatility and flexibility allow for greater customization and precision, making it an excellent option for a wide range of applications.
4. Lapping and Clearance
Wire fibres come in various sizes to suit different requirements, making lapping unnecessary in most cases. However, when lapping is necessary, it is recommended to have a minimum of 6 inches of lapping.
To ensure proper installation, a clearance of 1 to 3 inches is typically provided between the wire fabric and formwork as a standard practice. This clearance helps to prevent any potential issues that may arise due to contact between the wire fabric and formwork. By providing this clearance, the wire fabric can be installed without causing any damage or obstruction to the formwork.
5. Vibrating
It is advisable to use plastic concrete that vibrates and is reinforced with welded fibre mesh to achieve a uniform distribution of the mixture and ensure proper embedding of the fabric. This technique helps to decrease the likelihood of cracking.
By utilizing vibrating plastic concrete, the mixture can be spread evenly throughout the material, guaranteeing that every part of it is adequately reinforced. In addition, the welded fibre mesh can be completely embedded in the mixture, further enhancing its overall strength and durability.
Cracking can be a major concern when working with concrete. However, by using this method, the risk of cracking can be significantly reduced. This is due to the fact that the mixture is distributed evenly and the fabric is properly embedded throughout, which minimizes weak points and potential vulnerabilities. Overall, the use of vibrating plastic concrete reinforced with welded fibre mesh is a highly recommended technique for ensuring the structural integrity and longevity of concrete structures.
Comparison between Welded Wire Fibre and Conventional Reinforcement
| Welded Wire Fabric | Conventional Reinforcement |
| Increased permeability. | Reduction of permeability |
| Bond can deteriorate over time | Bonds effectively with concrete permanently |
| No surface protection provided | Improves surface durability |
| Minor resistance provided if properly placed | Improves impact, shatter and abrasion resistance |
| Difficult to install and expensive – high labor costs | Easy to use and cost effective – no labor costs |
| Difficult to place, especially if rolls – 1″ minimum cover required | Easy to place in concrete mix – No minimum cover |
| No effect on finish, but difficult to maintain placement in slab | Easy to finish with minor effect on workability of mix |
| Will deteriorate if not properly placed and protected | Alkali resistant |
| Will deteriorate if not properly placed and protected | Acid resistant |
| Corrodes when exposed to water and chemicals | Corrosion resistant |
| Increases tensile strength if properly placed | Increases tensile strength of plain non-reinforced concrete |
| Provides reinforcement in one plane | Provides three dimensional reinforcement |
| Increases ductility if properly placed | Increases ductility |
| Permanent if visible with little remedy possible | No lasting aesthetics and can be easily remedied if necessary |
| Meets ASTM specifications if placed properly | Meets or exceeds ASTM specifications |
| Storage difficult and detrimental if stored outside | Can be stored for long periods of time |
Advantages of Welded Wire Fabric in Concrete
1. Higher Design Strength
According to the provided context, it can be stated that the behavior of welded wire fabric is equivalent to that of HYSD bars or plain mild steel bars in terms of their structural properties. The increased strength of welded wire fabric can be attributed to the characteristic strength of the welded wires.
In other words, the structural performance of welded wire fabric is comparable to that of traditional reinforcing bars made of mild steel or high-yield strength deformed steel (HYSD). This means that welded wire fabric can provide similar support and durability to reinforced concrete structures as these other materials.
The reason for the enhanced strength of welded wire fabric lies in the unique strength of the welded wires themselves. This implies that the welding process used to connect the wires enhances the overall strength of the resulting fabric, thereby making it a robust option for construction and engineering applications.
2. Better Bonding
Concrete bonding is primarily influenced by the peripheral surface area. However, in the case of welded wire fabric, the rigid mechanical interconnections through welds to cross-wires play a significant role in stress transfer between concrete and steel. The welded joints can withstand up to 210 N/mm2, allowing for fast and complete stress transfer within two welded joints from the critical section.
3. Effective Crack Resistance
Welded wire fibre is a material commonly used in concrete structures to reduce the occurrence of cracks. This is primarily attributed to two of its key properties – the strong mechanical anchorage of the welds at each intersection and the close spacing of thinner wires.
The mechanical anchorage of the welds at each intersection is an important factor in the effectiveness of welded wire fibre. This is because it ensures that the fibres remain securely embedded within the concrete, even under significant stresses. This anchorage is particularly beneficial in countering load-induced phenomena, such as those caused by heavy traffic or the movement of heavy machinery over a concrete surface.
In addition to the strong mechanical anchorage provided by the welds, the close spacing of the thinner wires in welded wire fibre is also critical in reducing cracks in concrete. This property serves as a highly effective countermeasure against non-load phenomena or strain-induced stresses, such as those caused by shrinkage or temperature changes. By preventing these stresses from causing cracks in the concrete, the close spacing of wires helps to preserve the structural integrity of the slab, ultimately prolonging its useful life.
4. Economical
Welded wire fabric offers a clear and decisive benefit, which is the ability to save time and labor. This advantage is evident and undeniable. With welded wire fabric, there is no need for cutting bars, marking them, or spacing them out. Furthermore, the arduous process of tying binding wires is entirely eliminated. This means that the use of welded wire fabric can lead to significant time and labor savings, making it an attractive option for construction projects.
5. Flexible in Handing and Placing
Welded wire fabric is a highly flexible material that can be easily handled due to the usage of thinner wires. This characteristic makes it an ideal choice for repair work involving re-plastering or guniting. Additionally, the fabric comes in long lengths in roll form, further adding to its convenience and suitability for a wide range of repair projects.
The flexibility of the material is especially useful in handling, as it allows for easy maneuvering and shaping to fit the specific repair requirements. This ensures that the fabric can be easily applied to any surface, providing a reliable and effective solution to repair work.
Moreover, the availability of the material in roll form and long lengths means that it can be easily transported and stored, reducing the time and effort required for repair projects. The convenience provided by the fabric’s form also means that it can be easily cut to size, making it an adaptable and versatile solution to various repair needs.
In conclusion, welded wire fabric’s flexibility, coupled with its availability in long lengths and roll form, makes it a highly convenient and practical material for repair work involving re-plastering or guniting. Its suitability for a wide range of repair projects, coupled with its ease of handling, make it an ideal solution for both professionals and DIY enthusiasts.
Uses of Welded Wire Fabric in Concrete
Welded wire fabric is a versatile and useful material in a wide range of construction projects. It is commonly used in the construction of structural flat slabs or in slabs with beam slab construction. This material is also ideal for large area floor slabs on ground, pavements, airport runways, and aprons as it helps achieve crack-free joint fewer surfaces.
In addition, welded wire fabric is suitable for creating concrete elements of curved or difficult shapes such as arches, domes, lotus petals, and other complex designs. Its flexibility and ease of use make it a valuable aid in the construction process.
The material is also useful in precast elements that are thin or difficult to reinforce, such as curved arch flat members, Hyperbolic Paraboloid Shells, folded plate roof girders, fins, thin pardis, or chajja drops. Moreover, it is commonly used in the mass production of standard precast R.C.C and prestressed elements like slab panels and wall panels.
Welded wire fabric can also be used as a bonding fabric during guniting or during re-plastering required for repairs and rehabilitation of structures. It is particularly helpful in unstressed shaping or form reinforcement used in Prestressed Concrete Girders of Box, I, T, or Double T-section.
Lastly, Ferrocement or Ferrocrete works where welded wire fabric is the only solution for forming the reinforcing matrix for precast elements such as water tanks, fins, shelves, and other similar structures. In summary, welded wire fabric is a versatile material that can be used in various construction projects, making it an important material in the industry.