Concrete has existed for millennia, with the earliest documented evidence pointing to 6,000 or even 7,000 BC. Since its early use on floors, cisterns, and walls, humans have looked into improving the durability and longevity of concrete by adding different materials to the mix. Modern concrete can utilize various supplementary cementitious materials (SCM) to provide the added performance boosts necessary to withstand challenging environmental conditions, consistent use, and heavy loads. However, while traditional SCMs can help address cracking there is one product alternative that is far superior at reducing cracking, micro or macro concrete fibers. This article takes a look at how concrete fibers reduce cracking, the applications of concrete fibers, information on supplementary cementitious materials, and ultimately how to purchase these performance-enhancing concrete fibers through R-E-D Industrial Products.
How Do Concrete Fibers Reduce Cracking?
Although not classified as supplementary cementitious material, adding concrete fibers to traditional cement helps work to prevent the appearance of cracks that can quickly diminish overall performance and longevity. Predominantly made from polypropylene, acrylic, glass, or natural cellulose materials, concrete fibers minimize the potential for shrinkage and subsequent cracking in concrete. These synthetic materials will not degrade over time, unlike some natural alternatives used in the past. Additionally, depending on the composition of the fiber, they may offer hydrophilic or hydrophobic properties that are beneficial to the end application. Polypropylene fibers are hydrophobic, repelling water, while polyvinyl (PVA) or nylon fibers are actively hydrophilic, absorbing nearby water molecules.
When mixed evenly throughout the concrete, these fibers inhibit the rapid evaporation or rise of water through the substrate, or an internal matrix, which helps to bind the material together and prevent early-stage cracking. With moisture and expansion due to freezing being the primary culprits behind cracked concrete, adding these synthetic fibers reduces the tension created in the concrete when drying.
Applications of Concrete Fibers for Reduced Cracks
Now that we know that concrete fibers are one of the best additives to address plastic shrinkage cracking, we can closely examine some of the applications of these additives. Considering concrete fibers can be added to precast concrete, shotcrete, and cast-in-place concrete, it makes them a highly versatile option across infrastructure projects, commercial structures, and even residential developments.
Bridges: Bridges, large and small, carry immensely heavy loads and are expected to ensure continual use, harsh weather conditions, and have a minimal impact on the surrounding environment. The presence of cracks in the concrete structure can impact longevity and resistance to adverse weather conditions that ultimately penetrate the surface and begin to erode the internal structure which will require continual maintenance or total replacement.
Commercial Structures: High-rises, hotels, office buildings, warehouses, and manufacturing centers are all prime examples of commercial structures that could utilize concrete fibers during construction. Concrete fibers can also provide an added boost to the insulation of these buildings. Keeping them cooler in the summer heat and warmer during the colder months.
Stadiums: Very few structures are designed to hold tens of thousands of people, withstand harsh environmental conditions, and provide reliable performance for several decades. Stadium construction is a premier candidate for reinforcement with concrete fibers. With underground infrastructure, walkways, multiple levels, and considerable internal design features, using concrete fibers to reinforce stadiums is a proven method of reducing cracking and protecting vital structures from erosion and degradation while minimizing required maintenance over the structures' lifetime.
Residential Development: Using concrete fibers in residential development projects can be an effective way to reduce overall costs and can help meet sustainability metrics outlined in the project goals. Concrete fibers are used to prevent plastic shrinkage cracking in sidewalks, driveways, patios, and other decorative or non-structural applications.
Available Supplementary Cementitious Materials
There are a wide variety of supplementary cementitious materials available with specific properties and benefits depending on the end application. These can range from the cast-off remnants of other industrial processes like fly ash or silica fume, or they can be engineered materials like R-E-D’s E5® Nano Products or Colloidal silica is uniquely suited to provide added protection against the damaging alkali-silica reaction due to the introduction of lithium.
SCMs like ground glass pozzolan and other slag replacement alternatives are exceptional products for reducing overall project carbon footprints while providing added strength and structural integrity. While many of these additives offer similar benefits, what is the best product to reduce cracking in the final product? The answer to this question is concrete fibers, which depending on the specific fiber length, can address both early-stage cracks and prevent cracks from developing well into final use.
Purchasing R-E-D Industrial Concrete Fibers
R-E-D Industrial Products has several decades of experience to support the claim that concrete fibers provide enhanced results towards reducing cracking versus supplementary cementitious materials. We’ve supplied countless customers with quality concrete fibers that reduce cracking, prevent shrinkage, limit costs, and provide dependable results no matter the application. Our intimate knowledge of the different types of concrete fibers and the benefits they offer make our team the ideal partnership for anyone looking to enhance the performance of their concrete structures. Be sure to visit our other recent articles on concrete fibers to learn more or reach out directly for more information or a quote on our products including SCMs.
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