Oxide jacking

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Oxide jacking has caused concrete spalling on walls of the Herbst Pavilion at Fort Mason Center in San Francisco Concrete spalling caused by oxide jacking at the Herbst Pavilion, Fort Mason Center, San Francisco.jpg
Oxide jacking has caused concrete spalling on walls of the Herbst Pavilion at Fort Mason Center in San Francisco

The expansive force of rusting , which may be called oxide jacking or rust burst, is a phenomenon that can cause damage to structures made of stone, masonry, concrete or ceramics, and reinforced with metal components. A definition is "the displacement of building elements due to the expansion of iron and steel products as the metal rusts and becomes iron oxide". [1] Corrosion of other metals such as aluminum can also cause oxide jacking.

Contents

Physical process

According to metallurgist Jack Harris, "Oxidation is usually accompanied by a net expansion so that when it occurs in a confined space stresses are generated in the metal component itself or in any surrounding medium such as stone or cement. So much energy is released by oxidation that the stresses generated are of sufficient magnitude to deform or fracture all known materials." [2]

As early as 1915, it was recognized that certain modern metal alloys are more susceptible to excessive oxidation when subjected to weathering than other metals. At that time, there was a trend to replace wrought iron fasteners with mild steel equivalents, which were less expensive. Unexpectedly, the mild steel fasteners failed in real world use much more quickly than anticipated, leading to a return to use of wrought iron in certain applications where length of service was important. [3]

Damage to notable buildings

These original Horses of Saint Mark have been relocated indoors, and replaced by replicas. Horses of Basilica San Marco bright.jpg
These original Horses of Saint Mark have been relocated indoors, and replaced by replicas.
The cornice at the top of the Land Title Building was damaged by oxide jacking. Land Title Building.JPG
The cornice at the top of the Land Title Building was damaged by oxide jacking.
Oxide jacking damage was discovered after a flood at the Farnsworth House. Mies van der Rohe photo Farnsworth House Plano USA 9.jpg
Oxide jacking damage was discovered after a flood at the Farnsworth House.

In a 1987 article in New Scientist , Jack Harris reported that oxide jacking has caused significant damage to many historic structures in the United Kingdom, including St Paul's Cathedral, the British Museum and the Albert Memorial in London, Gloucester Cathedral, St. Margaret's Church in King's Lynn, Winchester Cathedral, and Blackburn Cathedral. [4]

Harris also wrote that oxide jacking also damaged the ancient Horses of Saint Mark on the exterior of St. Mark's Basilica in Venice. Expansive rusting of iron and steel bolts and reinforcements affected the structural integrity of the copper horse sculptures, which were relocated indoors and replaced with replicas. Poorly-designed early 20th-century renovations also led to oxide jacking damage to the Acropolis of Athens. [4]

In the United States, rusting of iron pegs inserted into holes in the stone entrance stair in order to support handrails resulted in cracking of the steps at the Basilica of the Sacred Heart in Notre Dame, Indiana. [5]

Oxide jacking damaged the terra cotta cornice on the Land Title Building in Philadelphia, designed in 1897 and expanded in 1902 by pioneer skyscraper architect Daniel Burnham. [6] The Land Title complex, with its two interconnected towers, is on the National Register of Historic Places. By 1922, experts on architectural terra cotta were warning that the rusting of embedded iron fasteners could cause decorative building components to fail. [7] This 1902 cornice is nearly 9 feet (2.7 m) high, projects 7 feet (2.1 m) from the facade of the building and is 465 feet (142 m) long. The cornice was stabilized, steel anchors subject to rusting were replaced with new stainless steel anchors, and the cornice was completely renovated. The project was completed in 1991. [6]

Flooding in 2007 damaged the modernist Farnsworth House in Plano, Illinois, designed in 1945 by Ludwig Mies van der Rohe, and now owned by the National Trust for Historic Preservation. Among the damage discovered by an architect inspecting the house in 2007 was oxide jacking at the corners of the house's steel framework. [8] The house flooded again in 2008.

Damage to reinforced concrete bridges and buildings

Structures built of concrete and reinforced with metal rebar are also subject to damage by oxide jacking. Expansion of corroded rebar causes spalling of the concrete. Structures exposed to a marine environment, or where salt is used for de-icing purposes, are especially susceptible to this type of damage. [4] This may also be caused by concrete having been installed without sufficient cover for the rebars, allowing moisture to reach the metal and cause oxidation.

Research in the 1960s showed that 22 percent of concrete bridge decks in Pennsylvania showed signs of spalling due to oxide jacking within four years of construction. Oxide jacking caused widespread damage to concrete council houses built in the United Kingdom in the post World War II era. [4]

According to an expert in the field, the problem resulted in "intensive worldwide research into the causes and repair of reinforcement corrosion, which in turn led to a vast output of research papers, conferences and publications on the subject." [9]

Damage to stone countertops

Countertop components fabricated out of granite and other natural stones are sometimes reinforced with metal rods inserted into grooves cut into the underside of the stone, and bonded in place with various resins. This procedure is called "rodding" by countertop fabricators. Most commonly, these rods will be placed near sink cutouts to prevent cracking of the brittle stone countertop during transportation and installation. [10] Data published by the Marble Institute of America shows that this technique results in a 600% increase in the deflection strength of the component. [11]

However, if a metal rod subject to oxidation or other forms of corrosion is used, and moisture from a sink or faucet reaches the rod, oxide jacking can crack the countertop directly above the rod. [12] Mild steel and some grades of aluminium rods are known to cause oxide jacking failures in granite countertops. Skilled stone repair professionals can disassemble the cracked stone, remove the metal rod, and reassemble the stone using various resins tinted to match the colors of the stone. [11] This type of problem can be prevented by using reinforcing rods made of stainless steel or fiberglass in the rodding procedure. [11]

See also

Related Research Articles

<span class="mw-page-title-main">Rust</span> Type of iron oxide

Rust is an iron oxide, a usually reddish-brown oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides (Fe2O3·nH2O) and iron(III) oxide-hydroxide (FeO(OH), Fe(OH)3), and is typically associated with the corrosion of refined iron.

<span class="mw-page-title-main">Stainless steel</span> Steel alloy resistant to corrosion

Stainless steel is an alloy of iron that is resistant to rusting and corrosion. It contains at least 11% chromium and may contain elements such as carbon and other nonmetals to obtain other desired properties. Stainless steel's resistance to corrosion results from the chromium, which forms a passive film that can protect the material and self-heal in the presence of oxygen.

<span class="mw-page-title-main">Reinforced concrete</span> Concrete with rebar

Reinforced concrete (RC), also called reinforced cement concrete (RCC) and ferroconcrete, is a composite material in which concrete's relatively low tensile strength and ductility are compensated for by the inclusion of reinforcement having higher tensile strength or ductility. The reinforcement is usually, though not necessarily, steel bars (rebar) and is usually embedded passively in the concrete before the concrete sets. However, post-tensioning is also employed as a technique to reinforce the concrete. In terms of volume used annually, it is one of the most common engineering materials. In corrosion engineering terms, when designed correctly, the alkalinity of the concrete protects the steel rebar from corrosion.

<span class="mw-page-title-main">Corrosion</span> Gradual destruction of materials by chemical reaction with its environment

Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials by chemical or electrochemical reaction with their environment. Corrosion engineering is the field dedicated to controlling and preventing corrosion.

<span class="mw-page-title-main">Rebar</span> Steel reinforcement

Rebar, known when massed as reinforcing steel or reinforcement steel, is a steel bar used as a tension device in reinforced concrete and reinforced masonry structures to strengthen and aid the concrete under tension. Concrete is strong under compression, but has low tensile strength. Rebar significantly increases the tensile strength of the structure. Rebar's surface features a continuous series of ribs, lugs or indentations to promote a better bond with the concrete and reduce the risk of slippage.

<span class="mw-page-title-main">Ferrocement</span>

Ferrocement or ferro-cement is a system of construction using reinforced mortar or plaster applied over an "armature" of metal mesh, woven, expanded metal, or metal-fibers, and closely spaced thin steel rods such as rebar. The metal commonly used is iron or some type of steel, and the mesh is made with wire with a diameter between 0.5 mm and 1 mm. The cement is typically a very rich mix of sand and cement in a 3:1 ratio; when used for making boards, no gravel is used, so that the material is not concrete.

<span class="mw-page-title-main">Steel frame</span> Building technique using skeleton frames of vertical steel columns

Steel frame is a building technique with a "skeleton frame" of vertical steel columns and horizontal I-beams, constructed in a rectangular grid to support the floors, roof and walls of a building which are all attached to the frame. The development of this technique made the construction of the skyscraper possible.

Microbial corrosion, also called microbiologically influenced corrosion (MIC), microbially induced corrosion (MIC) or biocorrosion, is "corrosion affected by the presence or activity (or both) of microorganisms in biofilms on the surface of the corroding material." This corroding material can be either a metal (such as steel or aluminum alloys) or a nonmetal (such as concrete or glass).

Rustproofing is the prevention or delay of rusting of iron and steel objects, or the permanent protection against corrosion. Typically, the protection is achieved by a process of surface finishing or treatment. Depending on mechanical wear or environmental conditions, the degradation may not be stopped completely, unless the process is periodically repeated. The term is particularly used in the automobile industry.

<span class="mw-page-title-main">Architectural terracotta</span> Fired clay construction material

Architectural terracotta refers to a fired mixture of clay and water that can be used in a non-structural, semi-structural, or structural capacity on the exterior or interior of a building. Terracotta pottery, as earthenware is called when not used for vessels, is an ancient building material that translates from Latin as "baked earth". Some architectural terracotta is actually the stronger stoneware. It can be unglazed, painted, slip glazed, or glazed. A piece of terracotta is composed of a hollow clay web enclosing a void space or cell. The cell can be installed in compression with mortar or hung with metal anchors. All cells are partially backfilled with mortar.

Concrete cover, in reinforced concrete, is the least distance between the surface of embedded reinforcement and the outer surface of the concrete. The concrete cover depth can be measured with a cover meter.

<span class="mw-page-title-main">Architectural metals</span>

Metals used for architectural purposes include lead, for water pipes, roofing, and windows; tin, formed into tinplate; zinc, copper and aluminium, in a range of applications including roofing and decoration; and iron, which has structural and other uses in the form of cast iron or wrought iron, or made into steel. Metal alloys used in building include bronze ; brass ; monel metal and nickel silver, mainly consisting of nickel and copper; and stainless steel, with important components of nickel and chromium.

<span class="mw-page-title-main">Rebar spacer</span>

A rebar spacer is a device that secures the reinforcing steel or "rebar" in reinforced concrete structures as the rebar is assembled in place before the final concrete pour. The spacers are left in place for the pour to keep the reinforcing in place. After the pour, the spacers become a part of the structure.

<span class="mw-page-title-main">Ironworker</span> Tradesman who works in the ironworking industry

An ironworker is a tradesman who works in the iron-working industry. Ironworkers assemble the structural framework in accordance with engineered drawings and install the metal support pieces for new buildings. They also repair and renovate old structures using reinforced concrete and steel. Ironworkers may work on factories, steel mills, and utility plants.

<span class="mw-page-title-main">Structural material</span>

Structural engineering depends on the knowledge of materials and their properties, in order to understand how different materials resist and support loads.

<span class="mw-page-title-main">Concrete degradation</span> Damage to concrete affecting its mechanical strength and its durability

Concrete degradation may have many different causes. Concrete is mostly damaged by the corrosion of reinforcement bars due to the carbonatation of hardened cement paste or chloride attack under wet conditions. Chemical damages are caused by the formation of expansive products produced by various chemical reactions, by aggressive chemical species present in groundwater and seawater, or by microorganisms. Other damaging processes can also involve calcium leaching by water infiltration and different physical phenomena initiating cracks formation and propagation. All these detrimental processes and damaging agents adversely affects the concrete mechanical strength and its durability.

Calcium nitrite is an inorganic compound with the chemical formula Ca(NO
2
)
2
. In this compound, as in all nitrites, nitrogen is in a +3 oxidation state. It has many applications such as antifreeze, rust inhibitor of steel and wash heavy oil.

<span class="mw-page-title-main">Conservation and restoration of shipwreck artifacts</span>

The conservation and restoration of shipwreck artifacts is the process of caring for cultural heritage that has been part of a shipwreck. Oftentimes these cultural artifacts have been underwater for a great length of time. Without conservation, most artifacts would perish and important historical data would be lost. In archaeological terms, it is usually the responsibility of an archaeologist and conservator to ensure that material recovered from a shipwreck is properly cared for. The conservation phase is often time-consuming and expensive, which is one of the most important considerations when planning and implementing any action involving the recovery of artifacts from a shipwreck.

<span class="mw-page-title-main">Conservation and restoration of lighthouses</span>

The conservation and restoration of lighthouses is when lighthouse structures are preserved through detailed examination, cleaning, and in-kind replacement of materials. Given the wide variety of materials used to construct lighthouses, a variety of techniques and considerations are required. Lighthouses alert seagoers of rocky shores nearby and provide landmark navigation. They also act as a physical representation to maritime history and advancement. These historic buildings are prone to deterioration due to their location on rocky outcrops of land near the water, as well as severe weather events, and the continued rise of sea levels. Given these conditions preservation and conservation efforts have increased.

The durability design of reinforced concrete structures has been recently introduced in national and international regulations. It is required that structures are designed to preserve their characteristics during the service life, avoiding premature failure and the need of extraordinary maintenance and restoration works. Considerable efforts have therefore made in the last decades in order to define useful models describing the degradation processes affecting reinforced concrete structures, to be used during the design stage in order to assess the material characteristics and the structural layout of the structure.

References

  1. Bucher, Ward (1996). Dictionary of Building Preservation. New York: Wiley Interscience. p. 319. ISBN   0-471-14413-4.
  2. Harris, J.E. (1984). "Oxidation induced deformation and fracture". Advances in Fracture Research. Oxford: Pergamon Press: 3791–811. Retrieved October 23, 2022.
  3. "Rust and Mild Steel" (PDF). New York Times . July 18, 1915. Retrieved January 2, 2012.
  4. 1 2 3 4 Harris, Jack (15 January 1987). "The Expanding Problem of Rust: Try to solve one problem and you often create another. Rusting can arise this way, as is clear from edifices ancient and modern". New Scientist . London. pp. 44–47. Retrieved January 2, 2012.
  5. Winkler, Erhard M. (1997). Stone in Architecture: Properties, Durability (3rd ed.). Berlin: Springer-Verlag. p. 239. ISBN   3-540-57626-6.
  6. 1 2 Levine, Jeffrey S.; Donna Ann Harris (September 1991). "Stabilization and Repair of a Historic Terra Cotta Cornice". Preservation Tech Notes. Washington, DC: National Park Service.
  7. Hill, C.W. (October 1922). "Terra Cotta Problems Suggested for Discussion and Investigation". Journal of the American Ceramic Society. Easton, Pennsylvania: American Ceramic Society. 5 (10): 732–38. doi:10.1111/j.1151-2916.1922.tb17607.x . Retrieved January 2, 2012.
  8. Campagna, Barbara A. (August 25, 2007). "Rescuing an Icon - Mies van der Rohe's Farnsworth House". Cities and Memory. Retrieved January 2, 2012.
  9. Pullar-Strecker, Peter (2002). Concrete reinforcement corrosion: from assessment to repair decisions. London: Thomas Telford Publishing. ISBN   978-0-7277-3182-1.
  10. Padden, Kevin M. (April 2009). "Rodding: Is It Right For Me?". Surface Fabrication. Cygnus Business Media.
  11. 1 2 3 Heaphy, Jim; Heaphy, James (January 2010). "Beware of Countertop Failure Caused by Rust". Kitchen & Bath Design News. Fort Atkinson, Wisconsin: Cygnus Business Media . Retrieved January 24, 2012.
  12. Baldwin, Deborah (January 19, 2010). "When solving a problem creates a new one". This Old House magazine . New York City. Archived from the original on April 26, 2012. Retrieved January 2, 2012.