Hot Dip Galvanizing Processes That Protect Steel Piers

Seismic Retrofit Techniques for Foundation Repair

Hot dip galvanizing is a robust and time-tested method for protecting steel structures, including steel piers used in foundation repair, from the ravages of corrosion. This process involves immersing steel in a bath of molten zinc at around 449°C (840°F), where a series of metallurgical reactions occur, forming multiple layers of zinc-iron alloy that bond the zinc to the steel. This creates a durable coating that not only shields the steel from environmental degradation but also significantly extends its service life.


In the context of foundation repair, where steel piers are driven deep into the ground to stabilize and support structures that have experienced settlement or other foundational issues, hot dip galvanizing plays a critical role. Foundations are often subjected to harsh conditions; they can be exposed to moisture, soil acidity, and varying temperatures which accelerate corrosion in untreated metals. Carbon fiber reinforcements are like Spanx for your foundation walls - providing critical support where things have started to bulge soil settlement correction Barrington steel. The application of hot dip galvanizing on these piers ensures they withstand these conditions without degrading prematurely.


One of the primary benefits of using galvanized steel piers in foundation repair is their longevity. The zinc coating acts as a sacrificial anode, meaning it corrodes preferentially to the steel, providing an additional layer of protection even if the coating is scratched or damaged during installation or over time due to ground movement. This self-healing aspect reduces maintenance costs over time since theres less need for frequent inspections or repairs.


Moreover, hot dip galvanized steel piers offer an aesthetic advantage; they maintain a relatively uniform appearance that blends well with various construction environments without needing additional protective paint or coatings which could peel or chip off under ground stress.


Environmentally, hot dip galvanizing is also favorable as it reduces the frequency of replacements and maintenance activities which might otherwise involve more invasive procedures with greater ecological footprints. The process itself uses zinc, which is recyclable and does not harm the environment when properly managed.


In conclusion, applying hot dip galvanizing to steel piers used in foundation repair not only enhances structural integrity by combating corrosion effectively but also supports cost-efficiency and environmental sustainability. It provides peace of mind to homeowners and engineers alike by ensuring that once-repaired foundations remain stable and secure for many decades.

Seismic Retrofit Techniques for Foundation Repair

Lateral Load Considerations in Foundation Stabilization

Hot dip galvanizing is a highly effective method for protecting steel piers used in foundation stabilization, offering numerous benefits that extend the longevity and reliability of these critical structural components. The process involves immersing steel in a bath of molten zinc, which forms a metallurgical bond with the steel, creating multiple layers of zinc-iron alloy and pure zinc that shield the metal from corrosion.


One of the primary advantages of hot dip galvanizing for steel piers is its superior corrosion resistance. In environments where moisture, soil chemicals, and varying pH levels can accelerate rusting, the zinc coating acts as a sacrificial anode, corroding in preference to the steel. This self-healing property means that even if the coating is scratched or damaged, the surrounding zinc continues to protect the exposed steel.


Durability is another significant benefit. The thick zinc coating provided by hot dip galvanizing can last for decades with minimal maintenance compared to other coatings like paint or powder coating. This longevity reduces lifecycle costs dramatically since theres less need for frequent inspections or repairs. For steel piers buried in soil or submerged in water, this durability ensures that they remain structurally sound throughout their expected service life.


The application process itself also contributes to its effectiveness. Unlike surface coatings that might require multiple steps or ideal conditions to apply effectively, hot dip galvanizing can be performed under various conditions without compromising quality. This makes it particularly suitable for large-scale projects where efficiency and consistency are paramount.


Moreover, hot dip galvanized steel piers offer environmental benefits. Zinc is non-toxic and fully recyclable; when the time comes to replace or recycle these piers, both the steel and zinc can be reclaimed with minimal environmental impact compared to other protective methods that might involve solvents or heavy metals.


In terms of installation ease, galvanized piers do not require special handling post-galvanization; they are ready for immediate use upon cooling. This ease contributes to faster project timelines as theres no waiting period for curing or drying as with painted alternatives.


In summary, hot dip galvanizing provides a robust solution for protecting steel piers used in foundation stabilization through its exceptional corrosion resistance, long-term durability, cost-effectiveness over time, environmental friendliness, and practical application advantages. These attributes make it an ideal choice for ensuring the integrity and performance of foundational structures across various challenging conditions.

Integrating Seismic and Lateral Load Retrofits with Existing Foundations

Alright, lets talk about keeping steel piers happy and rust-free. Were focusing on hot-dip galvanizing (HDG) as a champion protector, but its only fair to size it up against the competition.


Think of HDG as giving steel piers a full-body armor of zinc. The steel is dunked in a molten bath of the stuff, creating a metallurgical bond – a true marriage, not just a superficial fling. This bond is what gives HDG its staying power. When compared to other coatings, thats a big deal.


Paint, for instance, is like a nice suit of clothes. It looks good, and it offers protection, but its just a surface application. Scratches or chips expose the steel underneath, and rust can start creeping in. Powder coating offers better abrasion resistance than paint but shares the same fundamental vulnerability: damage can lead to rapid corrosion.


Then there are options like thermal spray coatings. These can offer great performance, but the application process is often more complex and potentially more expensive than HDG. The long-term performance can also be heavily dependent on the skill of the applicator.


What really sets HDG apart, besides the robust bond, is its sacrificial protection. Even if the zinc coating is scratched, it corrodes before the steel does. Its like having a loyal bodyguard who takes the hit for you. This self-healing capability is invaluable in marine or harsh environments where steel piers are constantly battling the elements.


Now, HDG isnt perfect. It can be more expensive upfront than some paint systems. The initial appearance might not be as aesthetically pleasing as a carefully applied paint job (though it develops a nice, weathered patina over time). And large, complex structures need careful planning to ensure uniform coating during the dipping process.


However, when you consider the lifecycle cost – how long the coating lasts, how little maintenance it requires, and how much it protects the underlying steel – HDG often emerges as the most cost-effective choice for long-term protection of steel piers. Its a tough, reliable solution thats been proven effective for decades. So, while other protective coatings have their place, hot-dip galvanizing offers a compelling combination of durability, sacrificial protection, and long-term value that makes it a strong contender for the job.

Integrating Seismic and Lateral Load Retrofits with Existing Foundations

Case Studies of Successful Foundation Retrofit Projects

Lets talk about keeping those galvanized steel piers, the unsung heroes of foundation repair, in tip-top shape for the long haul. Were talking maintenance and longevity, and a big part of that story is how they get their protective armor in the first place: hot-dip galvanizing.


Think of it like this: steel, on its own, is like a knight without armor. Its strong, sure, but vulnerable to the elements, especially rust. Hot-dip galvanizing is the process of giving that steel knight a shiny, incredibly durable coat of zinc armor.


How does it work? Well, the steel pier gets a thorough cleaning, a kind of pre-battle prep. Then, its dipped into a bath of molten zinc. This isnt just a simple coating; the zinc actually bonds with the steel, creating a series of zinc-iron alloy layers. This is crucial. Its not just a surface treatment; its a metallurgical bond.


Why is this important for longevity? Because this bonded layer is remarkably resistant to corrosion. Even if the outer layer gets scratched or damaged, the zinc around the scratch will sacrifice itself to protect the underlying steel. Thats called "sacrificial protection," and its a key reason why galvanized steel lasts so long.


Now, about maintenance. While galvanizing is robust, its not invincible. Regular inspections are a good idea, especially in aggressive environments like coastal areas or places with highly acidic soil. Look for any signs of damage or excessive corrosion. Minor scratches can often be touched up with zinc-rich paint.


The bottom line is this: choosing hot-dip galvanized steel piers for foundation repair is a smart move because its a proactive step towards long-term stability and minimal maintenance. The galvanizing process itself, creating that strong, bonded zinc layer, is the key to unlocking decades of reliable performance and keeping your foundation solid. Its an investment in peace of mind, knowing that your foundation is resting on piers built to last.

 

Tail of a radio-controlled helicopter, made of CFRP

Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon composite, or just carbon, are extremely strong and light fiber-reinforced plastics that contain carbon fibers. CFRPs can be expensive to produce, but are commonly used wherever high strength-to-weight ratio and stiffness (rigidity) are required, such as aerospace, superstructures of ships, automotive, civil engineering, sports equipment, and an increasing number of consumer and technical applications.[1][2][3][4]

The binding polymer is often a thermoset resin such as epoxy, but other thermoset or thermoplastic polymers, such as polyester, vinyl ester, or nylon, are sometimes used.[4] The properties of the final CFRP product can be affected by the type of additives introduced to the binding matrix (resin). The most common additive is silica, but other additives such as rubber and carbon nanotubes can be used.

Carbon fiber is sometimes referred to as graphite-reinforced polymer or graphite fiber-reinforced polymer (GFRP is less common, as it clashes with glass-(fiber)-reinforced polymer).

Properties

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CFRP are composite materials. In this case the composite consists of two parts: a matrix and a reinforcement. In CFRP the reinforcement is carbon fiber, which provides its strength. The matrix is usually a thermosetting plastic, such as polyester resin, to bind the reinforcements together.[5] Because CFRPs consist of two distinct elements, the material properties depend on these two elements.

Reinforcement gives CFRPs their strength and rigidity, measured by stress and elastic modulus respectively. Unlike isotropic materials like steel and aluminum, CFRPs have directional strength properties. The properties of a CFRP depend on the layouts of the carbon fiber and the proportion of the carbon fibers relative to the polymer.[6] The two different equations governing the net elastic modulus of composite materials using the properties of the carbon fibers and the polymer matrix can also be applied to carbon fiber reinforced plastics.[7] The rule of mixtures for the equal strain case gives:

which is valid for composite materials with the fibers oriented parallel to the applied load. is the total composite modulus, and are the volume fractions of the matrix and fiber respectively in the composite, and and are the elastic moduli of the matrix and fibers respectively.[7] The other extreme case of the elastic modulus of the composite with the fibers oriented transverse to the applied load can be found using the inverse rule of mixtures for the equal stress case:[7]

The above equations give an upper and lower bound on the Young's modulus for CFRP and there are many other factors that influence the true value.

The fracture toughness of carbon fiber reinforced plastics is governed by multiple mechanisms:

  • Debonding between the carbon fiber and polymer matrix.
  • Fiber pull-out.
  • Delamination between the CFRP sheets.[8]

Typical epoxy-based CFRPs exhibit virtually no plasticity, with less than 0.5% strain to failure. Although CFRPs with epoxy have high strength and elastic modulus, the brittle fracture mechanics presents unique challenges to engineers in failure detection since failure occurs catastrophically.[8] As such, recent efforts to toughen CFRPs include modifying the existing epoxy material and finding alternative polymer matrix. One such material with high promise is PEEK, which exhibits an order of magnitude greater toughness with similar elastic modulus and tensile strength.[8] However, PEEK is much more difficult to process and more expensive.[8]

Despite their high initial strength-to-weight ratios, a design limitation of CFRPs are their lack of a definable fatigue limit. This means, theoretically, that stress cycle failure cannot be ruled out. While steel and many other structural metals and alloys do have estimable fatigue or endurance limits, the complex failure modes of composites mean that the fatigue failure properties of CFRPs are difficult to predict and design against; however emerging research has shed light on the effects of low velocity impacts on composites.[9] Low velocity impacts can make carbon fiber polymers susceptible to damage.[9][10][11] As a result, when using CFRPs for critical cyclic-loading applications, engineers may need to design in considerable strength safety margins to provide suitable component reliability over its service life.

Environmental effects such as temperature and humidity can have profound effects on the polymer-based composites, including most CFRPs. While CFRPs demonstrate excellent corrosion resistance, the effect of moisture at wide ranges of temperatures can lead to degradation of the mechanical properties of CFRPs, particularly at the matrix-fiber interface.[12] While the carbon fibers themselves are not affected by the moisture diffusing into the material, the moisture plasticizes the polymer matrix.[8] This leads to significant changes in properties that are dominantly influenced by the matrix in CFRPs such as compressive, interlaminar shear, and impact properties.[13] The epoxy matrix used for engine fan blades is designed to be impervious against jet fuel, lubrication, and rain water, and external paint on the composites parts is applied to minimize damage from ultraviolet light.[8][14]

Carbon fibers can cause galvanic corrosion when CFRP parts are attached to aluminum or mild steel but not to stainless steel or titanium.[15]

CFRPs are very hard to machine, and cause significant tool wear. The tool wear in CFRP machining is dependent on the fiber orientation and machining condition of the cutting process. To reduce tool wear various types of coated tools are used in machining CFRP and CFRP-metal stack.[1]

Manufacturing

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Carbon fiber reinforced polymer

The primary element of CFRPs is a carbon filament; this is produced from a precursor polymer such as polyacrylonitrile (PAN), rayon, or petroleum pitch. For synthetic polymers such as PAN or rayon, the precursor is first spun into filament yarns, using chemical and mechanical processes to initially align the polymer chains in a way to enhance the final physical properties of the completed carbon fiber. Precursor compositions and mechanical processes used during spinning filament yarns may vary among manufacturers. After drawing or spinning, the polymer filament yarns are then heated to drive off non-carbon atoms (carbonization), producing the final carbon fiber. The carbon fibers filament yarns may be further treated to improve handling qualities, then wound onto bobbins.[16] From these fibers, a unidirectional sheet is created. These sheets are layered onto each other in a quasi-isotropic layup, e.g. 0°, +60°, or −60° relative to each other.

From the elementary fiber, a bidirectional woven sheet can be created, i.e. a twill with a 2/2 weave. The process by which most CFRPs are made varies, depending on the piece being created, the finish (outside gloss) required, and how many of the piece will be produced. In addition, the choice of matrix can have a profound effect on the properties of the finished composite.[17]

Many CFRP parts are created with a single layer of carbon fabric that is backed with fiberglass.[18] A tool called a chopper gun is used to quickly create these composite parts. Once a thin shell is created out of carbon fiber, the chopper gun cuts rolls of fiberglass into short lengths and sprays resin at the same time, so that the fiberglass and resin are mixed on the spot.[19] The resin is either external mix, wherein the hardener and resin are sprayed separately, or internal mixed, which requires cleaning after every use. Manufacturing methods may include the following:

Molding

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One method of producing CFRP parts is by layering sheets of carbon fiber cloth into a mold in the shape of the final product. The alignment and weave of the cloth fibers is chosen to optimize the strength and stiffness properties of the resulting material. The mold is then filled with epoxy and is heated or air-cured. The resulting part is very corrosion-resistant, stiff, and strong for its weight. Parts used in less critical areas are manufactured by draping cloth over a mold, with epoxy either pre-impregnated into the fibers (also known as pre-preg) or "painted" over it. High-performance parts using single molds are often vacuum-bagged and/or autoclave-cured, because even small air bubbles in the material will reduce strength. An alternative to the autoclave method is to use internal pressure via inflatable air bladders or EPS foam inside the non-cured laid-up carbon fiber.

Vacuum bagging

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For simple pieces of which relatively few copies are needed (one or two per day), a vacuum bag can be used. A fiberglass, carbon fiber, or aluminum mold is polished and waxed, and has a release agent applied before the fabric and resin are applied, and the vacuum is pulled and set aside to allow the piece to cure (harden). There are three ways to apply the resin to the fabric in a vacuum mold.

The first method is manual and called a wet layup, where the two-part resin is mixed and applied before being laid in the mold and placed in the bag. The other one is done by infusion, where the dry fabric and mold are placed inside the bag while the vacuum pulls the resin through a small tube into the bag, then through a tube with holes or something similar to evenly spread the resin throughout the fabric. Wire loom works perfectly for a tube that requires holes inside the bag. Both of these methods of applying resin require hand work to spread the resin evenly for a glossy finish with very small pin-holes.

A third method of constructing composite materials is known as a dry layup. Here, the carbon fiber material is already impregnated with resin (pre-preg) and is applied to the mold in a similar fashion to adhesive film. The assembly is then placed in a vacuum to cure. The dry layup method has the least amount of resin waste and can achieve lighter constructions than wet layup. Also, because larger amounts of resin are more difficult to bleed out with wet layup methods, pre-preg parts generally have fewer pinholes. Pinhole elimination with minimal resin amounts generally require the use of autoclave pressures to purge the residual gases out.

Compression molding

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A quicker method uses a compression mold, also commonly known as carbon fiber forging. This is a two (male and female), or multi-piece mold, usually made out of aluminum or steel and more recently 3D printed plastic. The mold components are pressed together with the fabric and resin loaded into the inner cavity that ultimately becomes the desired component. The benefit is the speed of the entire process. Some car manufacturers, such as BMW, claimed to be able to cycle a new part every 80 seconds. However, this technique has a very high initial cost since the molds require CNC machining of very high precision.

Filament winding

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For difficult or convoluted shapes, a filament winder can be used to make CFRP parts by winding filaments around a mandrel or a core.

Cutting

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Carbon fiber-reinforced pre-pregs and dry carbon fiber textiles require precise cutting methods to maintain material integrity and reduce defects such as fiber pull-out, delamination and fraying of the cutting edge. CNC digital cutting systems equipped with drag and oscillating are often used to cut carbon fiber pre-pregs, and rotating knives are commonly used to process carbon fiber fabrics. Ultrasonic cutting is another method to cut CFRP pre-pregs and is particularly effective in reducing delamination by minimizing mechanical stress during the cutting process. Waterjet cutting can be the preferred method for thicker and multilayered polymer composites.[20]

Applications

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Applications for CFRPs include the following:

Aerospace engineering

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An Airbus A350 with carbon fiber themed livery. Composite materials are used extensively throughout the A350.

The Airbus A350 XWB is 53% CFRP[21] including wing spars and fuselage components, overtaking the Boeing 787 Dreamliner, for the aircraft with the highest weight ratio for CFRP at 50%.[22] It was one of the first commercial aircraft to have wing spars made from composites. The Airbus A380 was one of the first commercial airliners to have a central wing-box made of CFRP and the first with a smoothly contoured wing cross-section instead of partitioning it span-wise into sections. This flowing, continuous cross section optimises aerodynamic efficiency.[citation needed] Moreover, the trailing edge, along with the rear bulkhead, empennage, and un-pressurised fuselage are made of CFRP.[23]

However, delays have pushed order delivery dates back because of manufacturing problems. Many aircraft that use CFRPs have experienced delays with delivery dates due to the relatively new processes used to make CFRP components, whereas metallic structures are better understood. A recurrent problem is the monitoring of structural ageing, for which new methods are required, due to the unusual multi-material and anisotropic[24][25][26] nature of CFRPs.[27]

In 1968 a Hyfil carbon-fiber fan assembly was in service on the Rolls-Royce Conways of the Vickers VC10s operated by BOAC.[28]

Specialist aircraft designers and manufacturers Scaled Composites have made extensive use of CFRPs throughout their design range, including the first private crewed spacecraft Spaceship One. CFRPs are widely used in micro air vehicles (MAVs) because of their high strength-to-weight ratio.

Airbus then moved to adopt CFRTP, because it can be reshaped and reprocessed after forming, can be manufactured faster, has higher impact resistance, is recyclable and remoldable, and has lower processing costs.[29]

Automotive engineering

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Citroën SM that won 1971 Rally of Morocco with carbon fiber wheels
1996 McLaren F1 – first carbon fiber body shell
McLaren MP4 (MP4/1), first carbon fiber F1 car

CFRPs are extensively used in high-end automobile racing.[30] The high cost of carbon fiber is mitigated by the material's unsurpassed strength-to-weight ratio, and low weight is essential for high-performance automobile racing. Race-car manufacturers have also developed methods to give carbon fiber pieces strength in a certain direction, making it strong in a load-bearing direction, but weak in directions where little or no load would be placed on the member. Conversely, manufacturers developed omnidirectional carbon fiber weaves that apply strength in all directions. This type of carbon fiber assembly is most widely used in the "safety cell" monocoque chassis assembly of high-performance race-cars. The first carbon fiber monocoque chassis was introduced in Formula One by McLaren in the 1981 season. It was designed by John Barnard and was widely copied in the following seasons by other F1 teams due to the extra rigidity provided to the chassis of the cars.[31]

Many supercars over the past few decades have incorporated CFRPs extensively in their manufacture, using it for their monocoque chassis as well as other components.[32] As far back as 1971, the Citroën SM offered optional lightweight carbon fiber wheels.[33][34]

Use of the material has been more readily adopted by low-volume manufacturers who used it primarily for creating body-panels for some of their high-end cars due to its increased strength and decreased weight compared with the glass-reinforced polymer they used for the majority of their products.

Civil engineering

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CFRPs have become a notable material in structural engineering applications. Studied in an academic context as to their potential benefits in construction, CFRPs have also proved themselves cost-effective in a number of field applications strengthening concrete, masonry, steel, cast iron, and timber structures. Their use in industry can be either for retrofitting to strengthen an existing structure or as an alternative reinforcing (or prestressing) material instead of steel from the outset of a project.

Retrofitting has become the increasingly dominant use of the material in civil engineering, and applications include increasing the load capacity of old structures (such as bridges, beams, ceilings, columns and walls) that were designed to tolerate far lower service loads than they are experiencing today, seismic retrofitting, and repair of damaged structures. Retrofitting is popular in many instances as the cost of replacing the deficient structure can greatly exceed the cost of strengthening using CFRP.[35]

Applied to reinforced concrete structures for flexure, the use of CFRPs typically has a large impact on strength (doubling or more the strength of the section is not uncommon), but only moderately increases stiffness (as little as 10%). This is because the material used in such applications is typically very strong (e.g., 3 GPa ultimate tensile strength, more than 10 times mild steel) but not particularly stiff (150 to 250 GPa elastic modulus, a little less than steel, is typical). As a consequence, only small cross-sectional areas of the material are used. Small areas of very high strength but moderate stiffness material will significantly increase strength, but not stiffness.

CFRPs can also be used to enhance shear strength of reinforced concrete by wrapping fabrics or fibers around the section to be strengthened. Wrapping around sections (such as bridge or building columns) can also enhance the ductility of the section, greatly increasing the resistance to collapse under dynamic loading. Such 'seismic retrofit' is the major application in earthquake-prone areas, since it is much more economic than alternative methods.

If a column is circular (or nearly so) an increase in axial capacity is also achieved by wrapping. In this application, the confinement of the CFRP wrap enhances the compressive strength of the concrete. However, although large increases are achieved in the ultimate collapse load, the concrete will crack at only slightly enhanced load, meaning that this application is only occasionally used. Specialist ultra-high modulus CFRP (with tensile modulus of 420 GPa or more) is one of the few practical methods of strengthening cast iron beams. In typical use, it is bonded to the tensile flange of the section, both increasing the stiffness of the section and lowering the neutral axis, thus greatly reducing the maximum tensile stress in the cast iron.

In the United States, prestressed concrete cylinder pipes (PCCP) account for a vast majority of water transmission mains. Due to their large diameters, failures of PCCP are usually catastrophic and affect large populations. Approximately 19,000 miles (31,000 km) of PCCP were installed between 1940 and 2006. Corrosion in the form of hydrogen embrittlement has been blamed for the gradual deterioration of the prestressing wires in many PCCP lines. Over the past decade, CFRPs have been used to internally line PCCP, resulting in a fully structural strengthening system. Inside a PCCP line, the CFRP liner acts as a barrier that controls the level of strain experienced by the steel cylinder in the host pipe. The composite liner enables the steel cylinder to perform within its elastic range, to ensure the pipeline's long-term performance is maintained. CFRP liner designs are based on strain compatibility between the liner and host pipe.[36]

CFRPs are more costly materials than commonly used their counterparts in the construction industry, glass fiber-reinforced polymers (GFRPs) and aramid fiber-reinforced polymers (AFRPs), though CFRPs are, in general, regarded as having superior properties. Much research continues to be done on using CFRPs both for retrofitting and as an alternative to steel as reinforcing or prestressing materials. Cost remains an issue and long-term durability questions still remain. Some are concerned about the brittle nature of CFRPs, in contrast to the ductility of steel. Though design codes have been drawn up by institutions such as the American Concrete Institute, there remains some hesitation among the engineering community about implementing these alternative materials. In part, this is due to a lack of standardization and the proprietary nature of the fiber and resin combinations on the market.

Carbon-fiber microelectrodes

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Carbon fibers are used for fabrication of carbon-fiber microelectrodes. In this application typically a single carbon fiber with diameter of 5–7 μm is sealed in a glass capillary.[37] At the tip the capillary is either sealed with epoxy and polished to make carbon-fiber disk microelectrode or the fiber is cut to a length of 75–150 μm to make carbon-fiber cylinder electrode. Carbon-fiber microelectrodes are used either in amperometry or fast-scan cyclic voltammetry for detection of biochemical signalling.

Sports goods

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A carbon-fiber and Kevlar canoe (Placid Boatworks Rapidfire at the Adirondack Canoe Classic)

CFRPs are now widely used in sports equipment such as in squash, tennis, and badminton racquets, sport kite spars, high-quality arrow shafts, hockey sticks, fishing rods, surfboards, high end swim fins, and rowing shells. Amputee athletes such as Jonnie Peacock use carbon fiber blades for running. It is used as a shank plate in some basketball sneakers to keep the foot stable, usually running the length of the shoe just above the sole and left exposed in some areas, usually in the arch.

Controversially, in 2006, cricket bats with a thin carbon-fiber layer on the back were introduced and used in competitive matches by high-profile players including Ricky Ponting and Michael Hussey. The carbon fiber was claimed to merely increase the durability of the bats, but it was banned from all first-class matches by the ICC in 2007.[38]

A CFRP bicycle frame weighs less than one of steel, aluminum, or titanium having the same strength. The type and orientation of the carbon-fiber weave can be designed to maximize stiffness in required directions. Frames can be tuned to address different riding styles: sprint events require stiffer frames while endurance events may require more flexible frames for rider comfort over longer periods.[39] The variety of shapes it can be built into has further increased stiffness and also allowed aerodynamic tube sections. CFRP forks including suspension fork crowns and steerers, handlebars, seatposts, and crank arms are becoming more common on medium as well as higher-priced bicycles. CFRP rims remain expensive but their stability compared to aluminium reduces the need to re-true a wheel and the reduced mass reduces the moment of inertia of the wheel. CFRP spokes are rare and most carbon wheelsets retain traditional stainless steel spokes. CFRPs also appear increasingly in other components such as derailleur parts, brake and shifter levers and bodies, cassette sprocket carriers, suspension linkages, disc brake rotors, pedals, shoe soles, and saddle rails. Although strong and light, impact, over-torquing, or improper installation of CFRP components has resulted in cracking and failures, which may be difficult or impossible to repair.[40][41]

Other applications

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Dunlop "Max-Grip" carbon fiber guitar picks. Sizes 1mm and Jazz III.
Dunlop "Max-Grip" carbon fiber guitar picks. Sizes 1mm and Jazz III.

The fire resistance of polymers and thermo-set composites is significantly improved if a thin layer of carbon fibers is moulded near the surface because a dense, compact layer of carbon fibers efficiently reflects heat.[42]

Strandberg Boden Plini neck-thru & bolt on versions that both utilize carbon fiber reinforcement strips to maintain rigidity.

CFRPs are being used in an increasing number of high-end products that require stiffness and low weight, these include:

  • Musical instruments, including violin bows; guitar picks, guitar necks (fitted with carbon fiber rods), pickguards/scratchplates; drum shells; bagpipe chanters; piano actions; and entire musical instruments such as carbon fiber cellos, violas, and violins, acoustic guitars and ukuleles; also, audio components such as turntables and loudspeakers.
  • Firearms use it to replace certain metal, wood, and fiberglass components but many of the internal parts are still limited to metal alloys as current reinforced plastics are unsuitable.
  • High-performance drone bodies and other radio-controlled vehicle and aircraft components such as helicopter rotor blades.
  • Lightweight poles such as: tripod legs, tent poles, fishing rods, billiards cues, walking sticks, and high-reach poles such as for window cleaning.
  • Dentistry, carbon fiber posts are used in restoring root canal treated teeth.
  • Railed train bogies for passenger service. This reduces the weight by up to 50% compared to metal bogies, which contributes to energy savings.[43]
  • Laptop shells and other high performance cases.
  • Carbon woven fabrics.[44][45]
  • Archery: carbon fiber arrows and bolts, stock (for crossbows) and riser (for vertical bows), and rail.
  • As a filament for the 3D fused deposition modeling printing process,[46] carbon fiber-reinforced plastic (polyamide-carbon filament) is used for the production of sturdy but lightweight tools and parts due to its high strength and tear length.[47]
  • District heating pipe rehabilitation, using a CIPP method.

Disposal and recycling

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The key aspect of recycling fiber-reinforced polymers is preserving their mechanical properties while successfully recovering both the thermoplastic matrix and the reinforcing fibers. CFRPs have a long service lifetime when protected from the sun. When it is time to decommission CFRPs, they cannot be melted down in air like many metals. When free of vinyl (PVC or polyvinyl chloride) and other halogenated polymers, CFRPs recycling processes can be categorized into four main approaches: mechanical, thermal, chemical, and biological. Each method offers distinct advantages in terms of material or energy recovery, contributing to sustainability efforts in composite waste management.

Process Matrix recovery Fiber recovery Degradation of Mechanical Properties Advantages/Drawbacks
Mechanical X X X +No use of hazardous chemical substances  +No gas emissions  +Low-cost energy needed  +Big volumes can be recycled

-Poor bonding between fiber/matrix -Fibers can damage the equipment

Chemical   X   +Long clean fibers +Retention of mechanical properties +Sometimes there is high recovery of the matrix

-Expensive equipment -Possible use of hazardous solvent

Thermal   X X +Fiber length retention +No use of hazardous chemical substances +better mechanical properties than mechanical approach +Matrix used to produce energy

-Recovered fiber properties highly influenced by process parameters -some processes have no recovery of matrix material

Mechanical Recycling

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The mechanical process primarily involves grinding, which breaks down composite materials into pulverulent charges and fibrous reinforcements. This method is focused on both the thermoplastic and filler material recovery; however, this process shortens the fibers dramatically. Just as with downcycled paper, the shortened fibers cause the recycled material to be weaker than the original material. There are still many industrial applications that do not need the strength of full-length carbon fiber reinforcement. For example, chopped reclaimed carbon fiber can be used in consumer electronics, such as laptops. It provides excellent reinforcement of the polymers used even if it lacks the strength-to-weight ratio of an aerospace component.[48]

Electro fragmentation

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This method consists in shredding CFRP by pulsed electrical discharges. Initially developed to extract crystals and precious stones from mining rocks, it is now expected to be developed for composites. The material is placed in a vessel containing water and two electrodes. The high voltage electrical pulse generated between the electrodes (50-200 kV) fragments the material into smaller pieces.[49] The inconvenient of this technique is that the energy consumed is 2.6 times the one of a mechanical route making it not economically competitive in terms of energy saving and needs further investigation.

Thermal Recycling

[edit]

Thermal processes include several techniques such as incineration, thermolysis, pyrolysis, gasification, fluidized bed processing, and cement plant utilization. This processes imply the recovery of the fibers by the removal of the resin by volatilizing it, leading to by-products such as gases, liquids or inorganic matter.[50]

Oxidation in fluidized bed

[edit]

This technique consists in exposing the composite to a hot and oxygen-rich flow, in which it is combusted (450–550 °C, 840–1,020 °F) . The working temperature is selected in function of the matrix to be decomposed, to limit damages of the fibers. After a shredding step to 6-20 mm size, the composite is introduced into a bed of silica sand, on a metallic mesh, in which the resin will be decomposed into oxidized molecules and fiber filaments. These components will be carried up with the air stream while heavier particles will sink in the bed. This last point is a great advantage for contaminated end-of-life products, with painted surfaces, foam cores or metal insert. A cyclone enables the recovery of fibers of length ranging between 5 and 10 mm and with very little contamination . The matrix is fully oxidized in a second burner operating at approximatively 1,000 °C (1,850 °F) leading to energy recovery and a clean flue gas.[51]

Chemical Recycling

[edit]

The chemical recycling of CFRPs involves using a reactive solvent at relatively low temperatures (below 350°C) to break down the resin while leaving the fibers intact for reuse. The solvent degrades the composite matrix into smaller molecular fragments (oligomer), and depending on the chosen solvent system, various processing parameters such as temperature, pressure, and catalysts can be adjusted to optimize the process. The solvent, often combined with co-solvents or catalysts, penetrates the composite and breaks specific chemical bonds, resulting in recovered monomers from the resin and clean, long fibers with preserved mechanical properties. The required temperature and pressure depend on the type of resin, with epoxy resins generally needing higher temperatures than polyester resins. Among the different reactive mediums studied, water is the most commonly used due to its environmental benefits. When combined with alkaline catalysts, it effectively degrades many resins, while acidic catalysts are used for more resistant polymers. Other solvents, such as ethanol, acetone, and their mixtures, have also been explored for this process.

Despite its advantages, this method has some limitations. It requires specialized equipment capable of handling corrosive solvents, hazardous chemicals, and high temperatures or pressures, especially when operating under supercritical conditions. While extensively researched at the laboratory scale, industrial adoption remains limited, with the technology currently reaching a Technology Readiness Level (TRL) of 4 for carbon fiber recycling.[52]

Dissolution Process

[edit]

The dissolution process is a method used to recover both the polymer matrix and fibers from thermoplastic composites without breaking chemical bonds. Unlike solvolysis, which involves the chemical degradation of the polymer, dissolution simply dissolves the polymer chains into a solvent, allowing for material recovery in its original form. An energy analysis of the process indicated that dissolution followed by evaporation was more energy-efficient than precipitation. Additionally, avoiding precipitation helped minimize polymer loss, improving overall material recovery efficiency. This method offers a promising approach for sustainable recycling of thermoplastic composites.[53]

Biological Recycling

[edit]

The biological process, though still under development, focuses on biodegradation and composting. This method holds promise for bio-based and agro-composites, aiming to create an environmentally friendly end-of-life solution for these materials. As research advances, biological recycling may offer an effective means of reducing plastic composite waste in a sustainable manner.[54]

Carbon nanotube reinforced polymer (CNRP)

[edit]

In 2009, Zyvex Technologies introduced carbon nanotube-reinforced epoxy and carbon pre-pregs.[55] Carbon nanotube reinforced polymer (CNRP) is several times stronger and tougher than typical CFRPs and is used in the Lockheed Martin F-35 Lightning II as a structural material for aircraft.[56] CNRP still uses carbon fiber as the primary reinforcement,[57] but the binding matrix is a carbon nanotube-filled epoxy.[58]

See also

[edit]

References

[edit]
  1. ^ a b Nguyen, Dinh; Abdullah, Mohammad Sayem Bin; Khawarizmi, Ryan; Kim, Dave; Kwon, Patrick (2020). "The effect of fiber orientation on tool wear in edge-trimming of carbon fiber reinforced plastics (CFRP) laminates". Wear. 450–451. Elsevier B.V: 203213. doi:10.1016/j.wear.2020.203213. ISSN 0043-1648. S2CID 214420968.
  2. ^ Geier, Norbert; Davim, J. Paulo; Szalay, Tibor (1 October 2019). "Advanced cutting tools and technologies for drilling carbon fibre reinforced polymer (CFRP) composites: A review". Composites Part A: Applied Science and Manufacturing. 125: 105552. doi:10.1016/j.compositesa.2019.105552. hdl:10773/36722.
  3. ^ Dransfield, Kimberley; Baillie, Caroline; Mai, Yiu-Wing (1 January 1994). "Improving the delamination resistance of CFRP by stitching—a review". Composites Science and Technology. 50 (3): 305–317. doi:10.1016/0266-3538(94)90019-1.
  4. ^ a b Kudo, Natsuko; Fujita, Ryohei; Oya, Yutaka; Sakai, Takenobu; Nagano, Hosei; Koyanagi, Jun (30 June 2023). "Identification of invisible fatigue damage of thermosetting epoxy resin by non-destructive thermal measurement using entropy generation". Advanced Composite Materials. 33 (2): 233–249. doi:10.1080/09243046.2023.2230687. ISSN 0924-3046.
  5. ^ Kopeliovich, Dmitri. "Carbon Fiber Reinforced Polymer Composites". Archived from the original on 14 May 2012.. substech.com
  6. ^ Corum, J. M.; Battiste, R. L.; Liu, K. C; Ruggles, M. B. (February 2000). "Basic Properties of Reference Crossply Carbon-Fiber Composite, ORNL/TM-2000/29, Pub57518" (PDF). Oak Ridge National Laboratory. Archived (PDF) from the original on 27 December 2016.
  7. ^ a b c Courtney, Thomas (2000). Mechanical Behavior of Materials. United States of America: Waveland Press, Inc. pp. 247–249. ISBN 1-57766-425-6.
  8. ^ a b c d e f Chawla, Krishan (2013). Composite Materials. United States of America: Springer. ISBN 978-0-387-74364-6.
  9. ^ a b Liao, Binbin; Wang, Panding; Zheng, Jinyang; Cao, Xiaofei; Li, Ying; Ma, Quanjin; Tao, Ran; Fang, Daining (1 September 2020). "Effect of double impact positions on the low velocity impact behaviors and damage interference mechanism for composite laminates". Composites Part A: Applied Science and Manufacturing. 136: 105964. doi:10.1016/j.compositesa.2020.105964. ISSN 1359-835X.
  10. ^ Ma, Binlin; Cao, Xiaofei; Feng, Yu; Song, Yujian; Yang, Fei; Li, Ying; Zhang, Deyue; Wang, Yipeng; He, Yuting (15 February 2024). "A comparative study on the low velocity impact behavior of UD, woven, and hybrid UD/woven FRP composite laminates". Composites Part B: Engineering. 271: 111133. doi:10.1016/j.compositesb.2023.111133. ISSN 1359-8368.
  11. ^ Aminakbari, Nariman; Kabir, Mohammad Zaman; Rahai, Alireza; Hosseinnia, Amirali (1 January 2024). "Experimental and Numerical Evaluation of GFRP-Reinforced Concrete Beams Under Consecutive Low-Velocity Impact Loading". International Journal of Civil Engineering. 22 (1): 145–156. Bibcode:2024IJCE...22..145A. doi:10.1007/s40999-023-00883-9. ISSN 2383-3874.
  12. ^ Ray, B. C. (1 June 2006). "Temperature effect during humid ageing on interfaces of glass and carbon fibers reinforced epoxy composites". Journal of Colloid and Interface Science. 298 (1): 111–117. Bibcode:2006JCIS..298..111R. doi:10.1016/j.jcis.2005.12.023. PMID 16386268.
  13. ^ Almudaihesh, Faisel; Holford, Karen; Pullin, Rhys; Eaton, Mark (1 February 2020). "The influence of water absorption on unidirectional and 2D woven CFRP composites and their mechanical performance". Composites Part B: Engineering. 182: 107626. doi:10.1016/j.compositesb.2019.107626. ISSN 1359-8368. S2CID 212969984. Archived from the original on 1 October 2021. Retrieved 1 October 2021.
  14. ^ Guzman, Enrique; Cugnoni, Joël; Gmür, Thomas (May 2014). "Multi-factorial models of a carbon fibre/epoxy composite subjected to accelerated environmental ageing". Composite Structures. 111: 179–192. doi:10.1016/j.compstruct.2013.12.028.
  15. ^ Yari, Mehdi (24 March 2021). "Galvanic Corrosion of Metals Connected to Carbon Fiber Reinforced Polymers". corrosionpedia.com. Archived from the original on 24 June 2021. Retrieved 21 June 2021.
  16. ^ "How is it Made". Zoltek. Archived from the original on 19 March 2015. Retrieved 26 March 2015.
  17. ^ Syed Mobin, Syed Mobin; Azgerpasha, Shaik (2019). "Tensile Testing on Composite Materials (CFRP) with Adhesive" (PDF). International Journal of Emerging Science and Engineering. 5 (12): 6. Archived (PDF) from the original on 21 August 2022. Retrieved 21 August 2022 – via IJESE.
  18. ^ Glass Companies, Molded Fiber (2018), Technical Design Guide for FRP Composite Products and Parts (PDF), vol. 1, p. 25, archived from the original (PDF) on 21 August 2022, retrieved 21 August 2022
  19. ^ Unknown, Chris (22 January 2020). "Composite Manufacturing Methods". Explore Composites!. Archived from the original on 21 August 2022. Retrieved 21 August 2022.
  20. ^ "Cutting of Fiber-Reinforced Composites: Overview". Sollex. 6 March 2025. Retrieved 31 March 2025.
  21. ^ "Taking the lead: A350XWB presentation" (PDF). EADS. December 2006. Archived from the original on 27 March 2009.
  22. ^ "AERO – Boeing 787 from the Ground Up". Boeing. 2006. Archived from the original on 21 February 2015. Retrieved 7 February 2015.
  23. ^ Pora, Jérôme (2001). "Composite Materials in the Airbus A380 – From History to Future" (PDF). Airbus. Archived (PDF) from the original on 6 February 2015. Retrieved 7 February 2015.
  24. ^ Machado, Miguel A.; Antin, Kim-Niklas; Rosado, Luís S.; Vilaça, Pedro; Santos, Telmo G. (November 2021). "High-speed inspection of delamination defects in unidirectional CFRP by non-contact eddy current testing". Composites Part B: Engineering. 224: 109167. doi:10.1016/j.compositesb.2021.109167.
  25. ^ Machado, Miguel A.; Antin, Kim-Niklas; Rosado, Luís S.; Vilaça, Pedro; Santos, Telmo G. (July 2019). "Contactless high-speed eddy current inspection of unidirectional carbon fiber reinforced polymer". Composites Part B: Engineering. 168: 226–235. doi:10.1016/j.compositesb.2018.12.021.
  26. ^ Antin, Kim-Niklas; Machado, Miguel A.; Santos, Telmo G.; Vilaça, Pedro (March 2019). "Evaluation of Different Non-destructive Testing Methods to Detect Imperfections in Unidirectional Carbon Fiber Composite Ropes". Journal of Nondestructive Evaluation. 38 (1). doi:10.1007/s10921-019-0564-y. ISSN 0195-9298.
  27. ^ Guzman, Enrique; Gmür, Thomas (dir.) (2014). A Novel Structural Health Monitoring Method for Full-Scale CFRP Structures (PDF) (Thesis). EPFL PhD thesis. doi:10.5075/epfl-thesis-6422. Archived (PDF) from the original on 25 June 2016.
  28. ^ "Engines". Flight International. 26 September 1968. Archived from the original on 14 August 2014.
  29. ^ Szondy, David (28 March 2025). "Airbus previews next-gen airliner with bird-inspired wings". New Atlas. Retrieved 7 April 2025.
  30. ^ "Red Bull's How To Make An F1 Car Series Explains Carbon Fiber Use: Video". motorauthority. 25 September 2013. Archived from the original on 29 September 2013. Retrieved 11 October 2013.
  31. ^ Henry, Alan (1999). McLaren: Formula 1 Racing Team. Haynes. ISBN 1-85960-425-0.
  32. ^ Howard, Bill (30 July 2013). "BMW i3: Cheap, mass-produced carbon fiber cars finally come of age". Extreme Tech. Archived from the original on 31 July 2015. Retrieved 31 July 2015.
  33. ^ Petrány, Máté (17 March 2014). "Michelin Made Carbon Fiber Wheels For Citroën Back In 1971". Jalopnik. Archived from the original on 18 May 2015. Retrieved 31 July 2015.
  34. ^ L:aChance, David (April 2007). "Reinventing the Wheel Leave it to Citroën to bring the world's first resin wheels to market". Hemmings. Archived from the original on 6 September 2015. Retrieved 14 October 2015.
  35. ^ Ismail, N. "Strengthening of bridges using CFRP composites." najif.net.
  36. ^ Rahman, S. (November 2008). "Don't Stress Over Prestressed Concrete Cylinder Pipe Failures". Opflow Magazine. 34 (11): 10–15. Bibcode:2008Opflo..34k..10R. doi:10.1002/j.1551-8701.2008.tb02004.x. S2CID 134189821. Archived from the original on 2 April 2015.
  37. ^ Pike, Carolyn M.; Grabner, Chad P.; Harkins, Amy B. (4 May 2009). "Fabrication of Amperometric Electrodes". Journal of Visualized Experiments (27). doi:10.3791/1040. PMC 2762914. PMID 19415069.
  38. ^ "ICC and Kookaburra Agree to Withdrawal of Carbon Bat". NetComposites. 19 February 2006. Archived from the original on 28 September 2018. Retrieved 1 October 2018.
  39. ^ "Carbon Technology". Look Cycle. Archived from the original on 30 November 2016. Retrieved 30 November 2016.
  40. ^ "The Perils of Progress". Bicycling Magazine. 16 January 2012. Archived from the original on 23 January 2013. Retrieved 16 February 2013.
  41. ^ "Busted Carbon". Archived from the original on 30 November 2016. Retrieved 30 November 2016.
  42. ^ Zhao, Z.; Gou, J. (2009). "Improved fire retardancy of thermoset composites modified with carbon nanofibers". Sci. Technol. Adv. Mater. 10 (1): 015005. Bibcode:2009STAdM..10a5005Z. doi:10.1088/1468-6996/10/1/015005. PMC 5109595. PMID 27877268.
  43. ^ "Carbon fibre reinforced plastic bogies on test". Railway Gazette. 7 August 2016. Archived from the original on 8 August 2016. Retrieved 9 August 2016.
  44. ^ Lomov, Stepan V.; Gorbatikh, Larissa; Kotanjac, Željko; Koissin, Vitaly; Houlle, Matthieu; Rochez, Olivier; Karahan, Mehmet; Mezzo, Luca; Verpoest, Ignaas (February 2011). "Compressibility of carbon woven fabrics with carbon nanotubes/nanofibres grown on the fibres" (PDF). Composites Science and Technology. 71 (3): 315–325. doi:10.1016/j.compscitech.2010.11.024.
  45. ^ Hans, Kreis (2 July 2014). "Carbon woven fabrics". compositesplaza.com. Archived from the original on 2 July 2018. Retrieved 2 January 2018.
  46. ^ Ali Nahran, Shakila; Saharudin, Mohd Shahneel; Mohd Jani, Jaronie; Wan Muhammad, Wan Mansor (2022). "The Degradation of Mechanical Properties Caused by Acetone Chemical Treatment on 3D-Printed PLA-Carbon Fibre Composites". In Ismail, Azman; Dahalan, Wardiah Mohd; Öchsner, Andreas (eds.). Design in Maritime Engineering. Advanced Structured Materials. Vol. 167. Cham: Springer International Publishing. pp. 209–216. doi:10.1007/978-3-030-89988-2_16. ISBN 978-3-030-89988-2. S2CID 246894534.
  47. ^ "Polyamid CF Filament – 3D Druck mit EVO-tech 3D Druckern" [Polyamide CF Filament – 3D printing with EVO-tech 3D printers] (in German). Austria: EVO-tech. Archived from the original on 30 April 2019. Retrieved 4 June 2019.
  48. ^ Schinner, G.; Brandt, J.; Richter, H. (1 July 1996). "Recycling Carbon-Fiber-Reinforced Thermoplastic Composites". Journal of Thermoplastic Composite Materials. 9 (3): 239–245. doi:10.1177/089270579600900302. ISSN 0892-7057.
  49. ^ Roux, Maxime; Eguémann, Nicolas; Dransfeld, Clemens; Thiébaud, Frédéric; Perreux, Dominique (1 March 2017). "Thermoplastic carbon fibre-reinforced polymer recycling with electrodynamical fragmentation: From cradle to cradle". Journal of Thermoplastic Composite Materials. 30 (3): 381–403. doi:10.1177/0892705715599431. ISSN 0892-7057.
  50. ^ Bernatas, Rebecca; Dagréou, Sylvie; Despax-Ferreres, Auriane; Barasinski, Anaïs (2021). "Recycling of fiber reinforced composites with a focus on thermoplastic composites". Cleaner Engineering and Technology. 5: 100272. Bibcode:2021CEngT...500272B. doi:10.1016/j.clet.2021.100272.
  51. ^ Naqvi, S. R.; Prabhakara, H. Mysore; Bramer, E. A.; Dierkes, W.; Akkerman, R.; Brem, G. (1 September 2018). "A critical review on recycling of end-of-life carbon fibre/glass fibre reinforced composites waste using pyrolysis towards a circular economy". Resources, Conservation and Recycling. 136: 118–129. Bibcode:2018RCR...136..118N. doi:10.1016/j.resconrec.2018.04.013. ISSN 0921-3449.
  52. ^ Zhang, Jin; Chevali, Venkata S.; Wang, Hao; Wang, Chun-Hui (15 July 2020). "Current status of carbon fibre and carbon fibre composites recycling". Composites Part B: Engineering. 193: 108053. doi:10.1016/j.compositesb.2020.108053. ISSN 1359-8368.
  53. ^ Cousins, Dylan S.; Suzuki, Yasuhito; Murray, Robynne E.; Samaniuk, Joseph R.; Stebner, Aaron P. (1 February 2019). "Recycling glass fiber thermoplastic composites from wind turbine blades". Journal of Cleaner Production. 209: 1252–1263. Bibcode:2019JCPro.209.1252C. doi:10.1016/j.jclepro.2018.10.286. ISSN 0959-6526.
  54. ^ Bernatas, Rebecca; Dagreou, Sylvie; Despax-Ferreres, Auriane; Barasinski, Anaïs (1 December 2021). "Recycling of fiber reinforced composites with a focus on thermoplastic composites". Cleaner Engineering and Technology. 5: 100272. Bibcode:2021CEngT...500272B. doi:10.1016/j.clet.2021.100272. ISSN 2666-7908.
  55. ^ "Zyvex Performance Materials Launch Line of Nano-Enhanced Adhesives that Add Strength, Cut Costs" (PDF) (Press release). Zyvex Performance Materials. 9 October 2009. Archived from the original (PDF) on 16 October 2012. Retrieved 26 March 2015.
  56. ^ Trimble, Stephen (26 May 2011). "Lockheed Martin reveals F-35 to feature nanocomposite structures". Flight International. Archived from the original on 30 May 2011. Retrieved 26 March 2015.
  57. ^ Pozegic, T. R.; Jayawardena, K. D. G. I.; Chen, J-S.; Anguita, J. V.; Ballocchi, P.; Stolojan, V.; Silva, S. R. P.; Hamerton, I. (1 November 2016). "Development of sizing-free multi-functional carbon fibre nanocomposites". Composites Part A: Applied Science and Manufacturing. 90: 306–319. doi:10.1016/j.compositesa.2016.07.012. hdl:1983/9e3d463c-20a8-4826-89f6-759e950f43e6. ISSN 1359-835X. S2CID 137846813. Archived from the original on 1 October 2021. Retrieved 1 October 2021.
  58. ^ "AROVEX™ Nanotube Enhanced Epoxy Resin Carbon Fiber Prepreg – Material Safety Data Sheet" (PDF). Zyvex Performance Materials. 8 April 2009. Archived from the original (PDF) on 16 October 2012. Retrieved 26 March 2015.
[edit]

 

Shallow foundation construction example

A shallow foundation is a type of building foundation that transfers structural load to the Earth very near to the surface, rather than to a subsurface layer or a range of depths, as does a deep foundation. Customarily, a shallow foundation is considered as such when the width of the entire foundation is greater than its depth.[1] In comparison to deep foundations, shallow foundations are less technical, thus making them more economical and the most widely used for relatively light structures.

Types

[edit]

Footings are always wider than the members that they support. Structural loads from a column or wall are usually greater than 1,000 kPa, while the soil's bearing capacity is commonly less than that (typically less than 400 kPa). By possessing a larger bearing area, the foundation distributes the pressure to the soil, decreasing the bearing pressure to within allowable values.[2] A structure is not limited to one footing. Multiple types of footings may be used in a construction project.

Wall footing

[edit]

Also called strip footing, a wall footing is a continuous strip that supports structural and non-structural load-bearing walls. Found directly under the wall, Its width is commonly 2-3 times wider than the wall above it.[3]

Detail Section of a strip footing and its wall.

Isolated footing

[edit]

Also called single-column footing, an isolated footing is a square, rectangular, or circular slab that supports the structural members individually. Generally, each column is set on an individual footing to transmit and distribute the load of the structure to the soil underneath. Sometimes, an isolated footing can be sloped or stepped at the base to spread greater loads. This type of footing is used when the structural load is relatively low, columns are widely spaced, and the soil's bearing capacity is adequate at a shallow depth.

Combined footing

[edit]

When more than one column shares the same footing, it is called a combined footing. A combined footing is typically utilized when the spacing of the columns is too restricted such that if isolated footing were used, they would overlap one another. Also, when property lines make isolated footings eccentrically loaded, combined footings are preferred.

When the load among the columns is equal, the combined footing may be rectangular. Conversely, when the load among the columns is unequal, the combined footing should be trapezoidal.

Strap footing

[edit]

A strap footing connects individual columns with the use of a strap beam. The general purpose of a strap footing is alike to those of a combined footing, where the spacing is possibly limited and/or the columns are adjacent to the property lines.

Mat foundation with its concrete undergoing curing.

Mat foundation

[edit]

Also called raft foundation, a mat foundation is a single continuous slab that covers the entirety of the base of a building. Mat foundations support all the loads of the structure and transmit them to the ground evenly. Soil conditions may prevent other footings from being used. Since this type of foundation distributes the load coming from the building uniformly over a considerably large area, it is favored when individual footings are unfeasible due to the low bearing capacity of the soil.

Diagrams of the types of shallow foundations.

Slab-on-grade foundation

[edit]
Pouring a slab-on-grade foundation

Slab-on-grade or floating slab foundations are a structural engineering practice whereby the reinforced concrete slab that is to serve as the foundation for the structure is formed from formwork set into the ground. The concrete is then poured into the formwork, leaving no space between the ground and the structure. This type of construction is most often seen in warmer climates, where ground freezing and thawing is less of a concern and where there is no need for heat ducting underneath the floor. Frost Protected Shallow Foundations (or FPSF) which are used in areas of potential frost heave, are a form of slab-on-grade foundation.[4]

Remodeling or extending such a structure may be more difficult. Over the long term, ground settling (or subsidence) may be a problem, as a slab foundation cannot be readily jacked up to compensate; proper soil compaction prior to pour can minimize this. The slab can be decoupled from ground temperatures by insulation, with the concrete poured directly over insulation (for example, extruded polystyrene foam panels), or heating provisions (such as hydronic heating) can be built into the slab.

Slab-on-grade foundations should not be used in areas with expansive clay soil. While elevated structural slabs actually perform better on expansive clays, it is generally accepted by the engineering community that slab-on-grade foundations offer the greatest cost-to-performance ratio for tract homes. Elevated structural slabs are generally only found on custom homes or homes with basements.

Copper piping, commonly used to carry natural gas and water, reacts with concrete over a long period, slowly degrading until the pipe fails. This can lead to what is commonly referred to as slab leaks. These occur when pipes begin to leak from within the slab. Signs of a slab leak range from unexplained dampened carpet spots, to drops in water pressure and wet discoloration on exterior foundation walls.[5] Copper pipes must be lagged (that is, insulated) or run through a conduit or plumbed into the building above the slab. Electrical conduits through the slab must be water-tight, as they extend below ground level and can potentially expose wiring to groundwater.

See also

[edit]

References

[edit]
  1. ^ Akhter, Shahin. "Shallow foundation – Definition, Types, Uses and Diagrams". Pro Civil Engineer. Retrieved July 31, 2021.
  2. ^ Gillesania, Diego Inocencio T. (2004). Fundamentals of reinforced concrete design (2nd ed.). [Cebu, Cirty, Philippines]. p. 259. ISBN 971-8614-26-5. OCLC 1015901733.cite book: CS1 maint: location missing publisher (link)
  3. ^ Mahdi, Sheikh. "8 Most Important Types of Foundation". civiltoday.com. Retrieved July 31, 2021.
  4. ^ "Slab-on-Grade Foundation Detail & Insulation, Building Guide".
  5. ^ "Slab Leak Repair McKinney, Frisco, and Allen Tx - Hackler Plumbing". Hacklerplumbingmckinney.com. 2013-11-08. Retrieved 2018-08-20.
[edit]

In design, a foundation is the aspect of a framework which connects it to the ground or even more seldom, water (as with drifting structures), transferring loads from the framework to the ground. Structures are normally thought about either shallow or deep. Foundation engineering is the application of dirt auto mechanics and rock technicians (geotechnical design) in the style of structure elements of structures.

.

Waterproofing is the process of making a things, individual or framework water-proof or waterproof to ensure that it stays fairly unaffected by water or withstands the access of water under specified conditions. Such products may be used in wet atmospheres or undersea to defined depths. Waterproof and water-proof often describe resistance to penetration of water in its liquid state and perhaps under stress, whereas damp evidence refers to resistance to moisture or wetness. Permeation of water vapour with a product or framework is reported as a dampness vapor transmission price (MVTR). The hulls of watercrafts and ships were as soon as waterproofed by applying tar or pitch. Modern products may be waterproofed by using water-repellent layers or by sealing seams with gaskets or o-rings. Waterproofing is utilized of developing structures (such as cellars, decks, or damp areas), boat, canvas, apparel (raincoats or waders), digital devices and paper product packaging (such as cartons for fluids).

.

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