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73-416: Studcast walls are prefabricated, ready-to-erect, high-performance concrete walls that weigh half as much as standard concrete walls. A hybrid between architectural precast concrete and panelized light-gage cold-formed steel framing , studcast walls combine the best features of each material in a way nullifies each material's weaknesses. They have been widely used as an exterior and interior wall system for over

146-453: A beam , to better withstand compressive stress in the structure. Square and round tubular sections of steel can also be used, often filled with concrete. Steel beams are connected to the columns with bolts and threaded fasteners, and historically connected by rivets . The central "web" of the steel I-beam is often wider than a column web to resist the higher bending moments that occur in beams. Wide sheets of steel deck can be used to cover

219-403: A building which are all attached to the frame. The development of this technique made the construction of the skyscraper possible. Steel frame has displaced its predecessor, the iron frame , in the early 20th century. The rolled steel "profile" or cross section of steel columns takes the shape of the letter "Ɪ". The two wide flanges of a column are thicker and wider than the flanges on

292-474: A decade. Studcast concrete was developed by combining the best aspects of two familiar technologies: the durability, fast erection, and architectural versatility of precast concrete and the light weight and high strength of panelized cold-formed steel stud framing. Both materials are widely available and relatively affordable; the benefit of studcast lies in joining them in a complementary and affordable manner that eliminates each of their disadvantages. Studcast

365-411: A given year to that year's total emissions. The annual airborne fraction for CO 2 had been stable at 0.45 for the past six decades even as the emissions have been increasing. This means that the other 0.55 of emitted CO 2 is absorbed by the land and atmosphere carbon sinks within the first year of an emission. In the high-emission scenarios, the effectiveness of carbon sinks will be lower, increasing

438-400: A greenhouse gas would absorb over a given time frame after it has been added to the atmosphere (or emitted to the atmosphere). The GWP makes different greenhouse gases comparable with regard to their "effectiveness in causing radiative forcing ". It is expressed as a multiple of the radiation that would be absorbed by the same mass of added carbon dioxide (CO 2 ), which is taken as

511-404: A machine that transforms a coil of flat steel into precisely-cut and shaped studs and rails. Every bend and perforation needed to assemble the steel is also performed. Workers assemble the cut pieces into panels using simple tools; no specialized clamps or jigs are required. The panels are accurate to within 1/32 inch over 60 feet (20 m). Lightweight concrete slurry is pumped into

584-420: A minimum, as is shipping cost. At the job site, walls can be handled with light equipment. For a low-rise structure - for instance a school or commercial building - a fork lift is all that is needed to erect a wall. The low mass of the wall requires smaller foundations . This is a two-fold environmental benefit: first for the reduction in consumption and transportation of raw materials in general; second for

657-539: A molecule of X remains in the box. τ {\displaystyle \tau } can also be defined as the ratio of the mass m {\displaystyle m} (in kg) of X in the box to its removal rate, which is the sum of the flow of X out of the box ( F out {\displaystyle F_{\text{out}}} ), chemical loss of X ( L {\displaystyle L} ), and deposition of X ( D {\displaystyle D} ) (all in kg/s): If input of this gas into

730-414: A much shorter atmospheric lifetime than carbon dioxide, its GWP is much less over longer time periods, with a GWP-100 of 27.9 and a GWP-500 of 7.95. The contribution of each gas to the enhanced greenhouse effect is determined by the characteristics of that gas, its abundance, and any indirect effects it may cause. For example, the direct radiative effect of a mass of methane is about 84 times stronger than

803-445: A process known as water vapor feedback. It occurs because Clausius–Clapeyron relation establishes that more water vapor will be present per unit volume at elevated temperatures. Thus, local atmospheric concentration of water vapor varies from less than 0.01% in extremely cold regions and up to 3% by mass in saturated air at about 32 °C. Global warming potential (GWP) is an index to measure how much infrared thermal radiation

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876-503: A reference gas. Therefore, the GWP has a value of 1 for CO 2 . For other gases it depends on how strongly the gas absorbs infrared thermal radiation, how quickly the gas leaves the atmosphere, and the time frame being considered. For example, methane has a GWP over 20 years (GWP-20) of 81.2 meaning that, for example, a leak of a tonne of methane is equivalent to emitting 81.2 tonnes of carbon dioxide measured over 20 years. As methane has

949-408: A single number. Scientists instead say that while the first 10% of carbon dioxide's airborne fraction (not counting the ~50% absorbed by land and ocean sinks within the emission's first year) is removed "quickly", the vast majority of the airborne fraction – 80% – lasts for "centuries to millennia". The remaining 10% stays for tens of thousands of years. In some models, this longest-lasting fraction

1022-463: A six-inch panel of ordinary precast concrete weighs about 70 psf. The strength-to-weight ratio is high. The precast units can support their own weight and be lifted off the casting tables only 24 hours after casting, making cycle-time short and efficient. Large panel sizes are practical to cast and light enough to handle with lighter equipment, resulting in fewer panels to erect and fewer panel joints to seal. Double-sided studcast walls were awarded

1095-491: A variety of Atmospheric Chemistry Observational Databases . The table below shows the most influential long-lived, well-mixed greenhouse gases, along with their tropospheric concentrations and direct radiative forcings , as identified by the Intergovernmental Panel on Climate Change (IPCC). Abundances of these trace gases are regularly measured by atmospheric scientists from samples collected throughout

1168-520: Is a CO 2 molecule. The first 30 ppm increase in CO 2 concentrations took place in about 200 years, from the start of the Industrial Revolution to 1958; however the next 90 ppm increase took place within 56 years, from 1958 to 2014. Similarly, the average annual increase in the 1960s was only 37% of what it was in 2000 through 2007. Many observations are available online in

1241-416: Is a hybrid precast wall system that is lightweight, sustainable , fast-erecting, and compatible with a wide range of designs and architectural finishes . These composite walls can be made with as little as two inches of concrete thickness, as compared to six-to-ten inches for the typical precast panel. Utilizing lightweight aggregate , walls can weigh as little as 18 pounds/square foot (psf). For reference,

1314-535: Is a level which the Intergovernmental Panel on Climate Change (IPCC) says is "dangerous". Greenhouse gases are infrared active, meaning that they absorb and emit infrared radiation in the same long wavelength range as what is emitted by the Earth's surface, clouds and atmosphere. 99% of the Earth's dry atmosphere (excluding water vapor ) is made up of nitrogen ( N 2 ) (78%) and oxygen ( O 2 ) (21%). Because their molecules contain two atoms of

1387-598: Is also an environmental benefit, as reducing construction time reduces energy consumption of construction equipment and the impact of workers on the site. It has a built-in cavity for insulating materials and utilities. It needs no additional furring to receive interior finishes. Because studcast is made of concrete and steel, it does not support mold growth or pest infestation . It is also highly resistant to moisture infiltration , freeze/thaw , and condensation . It releases no volatile organic compounds (VOCs). The automated roll forming system produces components to

1460-407: Is also compatible with integral color . Form liners can be used to mold a variety of textures into the wall surface. These might include simulated masonry or stone textures, even carvings or decorative patterns. Architectural veneers such as thin brick or thin genuine stone are also options. Innovative materials such as crushed glass could also be cast into the surface. The material

1533-434: Is also cooling the upper atmosphere, as it is much thinner than the lower layers, and any heat re-emitted from greenhouse gases is more likely to travel further to space than to interact with the fewer gas molecules in the upper layers. The upper atmosphere is also shrinking as the result. Anthropogenic changes to the natural greenhouse effect are sometimes referred to as the enhanced greenhouse effect . This table shows

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1606-406: Is also suitable for decorative operations after casting. Carving, rasping , and gouging with hand-tools can create textures or contouring. Routed lines and grooves, reveals , digital cutting, and other power-tool working are also possible. Studcast is typically prefabricated for improved efficiency and quality control. The designer's CAD drawings are converted into computer instructions for

1679-489: Is an asymmetry in electric charge distribution which allows molecular vibrations to interact with electromagnetic radiation. This makes them infrared active, and so their presence causes greenhouse effect . Earth absorbs some of the radiant energy received from the sun, reflects some of it as light and reflects or radiates the rest back to space as heat . A planet's surface temperature depends on this balance between incoming and outgoing energy. When Earth's energy balance

1752-596: Is anchored to the floor and ceiling to outline each room. The vertical studs are arranged in the tracks, usually spaced 16 inches (410 mm) apart, and fastened at the top and bottom. The typical profiles used in residential construction are the C-shape stud and the U-shaped track, and a variety of other profiles. Framing members are generally produced in a thickness of 12 to 25 gauge . Heavy gauges, such as 12 and 14 gauge, are commonly used when axial loads (parallel to

1825-515: Is as large as 30%. Estimates in 2023 found that the current carbon dioxide concentration in the atmosphere may be the highest it has been in the last 14 million years. However the IPCC Sixth Assessment Report estimated similar levels 3 to 3.3 million years ago in the mid-Pliocene warm period . This period can be a proxy for likely climate outcomes with current levels of CO 2 . Greenhouse gas monitoring involves

1898-403: Is mostly due to the rapid growth and cumulative magnitude of the disturbances to Earth's carbon cycle by the geologic extraction and burning of fossil carbon. As of year 2014, fossil CO 2 emitted as a theoretical 10 to 100 GtC pulse on top of the existing atmospheric concentration was expected to be 50% removed by land vegetation and ocean sinks in less than about a century, as based on

1971-507: Is shifted, its surface becomes warmer or cooler, leading to a variety of changes in global climate. Radiative forcing is a metric calculated in watts per square meter, which characterizes the impact of an external change in a factor that influences climate. It is calculated as the difference in top-of-atmosphere (TOA) energy balance immediately caused by such an external change. A positive forcing, such as from increased concentrations of greenhouse gases, means more energy arriving than leaving at

2044-489: Is the level the United Nations' Intergovernmental Panel on Climate Change (IPCC) says is "dangerous". Most greenhouse gases have both natural and human-caused sources. An exception are purely human-produced synthetic halocarbons which have no natural sources. During the pre-industrial Holocene , concentrations of existing gases were roughly constant, because the large natural sources and sinks roughly balanced. In

2117-499: Is the most important greenhouse gas overall, being responsible for 41–67% of the greenhouse effect, but its global concentrations are not directly affected by human activity. While local water vapor concentrations can be affected by developments such as irrigation , it has little impact on the global scale due to its short residence time of about nine days. Indirectly, an increase in global temperatures cause will also increase water vapor concentrations and thus their warming effect, in

2190-441: Is true that hot rolled steel members often have a higher initial cost per component when compared to cold rolled steel, their cost-efficiency becomes increasingly evident when used in the construction of larger structures. This is due to the fact that hot rolled steel frames require fewer components to span equivalent distances, leading to economic advantages in bigger projects. The use of steel instead of iron for structural purposes

2263-712: Is warmed by sunlight, causing its surface to radiate heat , which is then mostly absorbed by greenhouse gases. Without greenhouse gases in the atmosphere, the average temperature of Earth's surface would be about −18 °C (0 °F), rather than the present average of 15 °C (59 °F). The five most abundant greenhouse gases in Earth's atmosphere, listed in decreasing order of average global mole fraction , are: water vapor , carbon dioxide , methane , nitrous oxide , ozone . Other greenhouse gases of concern include chlorofluorocarbons (CFCs and HCFCs ), hydrofluorocarbons (HFCs), perfluorocarbons , SF 6 , and NF 3 . Water vapor causes about half of

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2336-404: Is well established and continually expanding due to the creativity of designers and innovation of precasters. The heavy weight of concrete panels remains a limiting factor, however. That entire gamut of aesthetic possibilities applies to studcast, in a package that can weigh only 20% of a typical precast panel. The fine texture of the concrete makes it well suited to architectural finishes . It

2409-563: The Hospitality Design and ASID Earth Minded Award for a product in 2009 . They were cited for their role in sustainable hospitality design. Both the material and process fit within the principles of sustainable construction . A studcast wall is both frame and skin . It can be dropped into place and bolted down, framing and enclosing the structure in a single step. This creates time and material savings that can potentially substantially reduce construction costs and time. This

2482-526: The greenhouse effect is heavily driven by water vapor , human emissions of water vapor are not a significant contributor to warming. The annual "Emissions Gap Report" by UNEP stated in 2022 that it was necessary to almost halve emissions. "To get on track for limiting global warming to 1.5°C, global annual GHG emissions must be reduced by 45 per cent compared with emissions projections under policies currently in place in just eight years, and they must continue to decline rapidly after 2030, to avoid exhausting

2555-469: The atmosphere into bodies of water (ocean, lakes, etc.), as well as dissolving in precipitation as raindrops fall through the atmosphere. When dissolved in water, carbon dioxide reacts with water molecules and forms carbonic acid , which contributes to ocean acidity . It can then be absorbed by rocks through weathering . It also can acidify other surfaces it touches or be washed into the ocean. The vast majority of carbon dioxide emissions by humans come from

2628-427: The atmosphere, terrestrial ecosystems , the ocean, and sediments . These flows have been fairly balanced over the past 1 million years, although greenhouse gas levels have varied widely in the more distant past . Carbon dioxide levels are now higher than they have been for 3 million years. If current emission rates continue then global warming will surpass 2.0 °C (3.6 °F) sometime between 2040 and 2070. This

2701-459: The atmospheric fraction of CO 2 even though the raw amount of emissions absorbed will be higher than in the present. Major greenhouse gases are well mixed and take many years to leave the atmosphere. The atmospheric lifetime of a greenhouse gas refers to the time required to restore equilibrium following a sudden increase or decrease in its concentration in the atmosphere. Individual atoms or molecules may be lost or deposited to sinks such as

2774-423: The balance between sources (emissions of the gas from human activities and natural systems) and sinks (the removal of the gas from the atmosphere by conversion to a different chemical compound or absorption by bodies of water). The proportion of an emission remaining in the atmosphere after a specified time is the " airborne fraction " (AF). The annual airborne fraction is the ratio of the atmospheric increase in

2847-534: The base material for the manufacture of cold-formed steel profiles. Sheet steel is then roll-formed into the final profiles used for framing. The sheets are zinc coated (galvanized) to increase protection against oxidation and corrosion . Steel framing provides excellent design flexibility due to the high strength-to-weight ratio of steel, which allows it to span over long distances, and also resist wind and earthquake loads. Steel-framed walls can be designed to offer excellent thermal and acoustic properties – one of

2920-502: The box ceased, then after time τ {\displaystyle \tau } , its concentration would decrease by about 63%. Changes to any of these variables can alter the atmospheric lifetime of a greenhouse gas. For instance, methane's atmospheric lifetime is estimated to have been lower in the 19th century than now, but to have been higher in the second half of the 20th century than after 2000. Carbon dioxide has an even more variable lifetime, which cannot be specified down to

2993-443: The building to partially collapse. In the case of the columns this is usually done by encasing it in some form of fire resistant structure such as masonry, concrete or plasterboard. The beams may be cased in concrete, plasterboard or sprayed with a coating to insulate it from the heat of the fire or it can be protected by a fire-resistant ceiling construction. Asbestos was a popular material for fireproofing steel structures up until

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3066-401: The burning of fossil fuels , with remaining contributions from agriculture and industry . Methane emissions originate from agriculture, fossil fuel production, waste, and other sources. The carbon cycle takes thousands of years to fully absorb CO 2 from the atmosphere, while methane lasts in the atmosphere for an average of only 12 years. Natural flows of carbon happen between

3139-405: The burning of fossil fuels . Additional contributions come from cement manufacturing, fertilizer production, and changes in land use like deforestation . Methane emissions originate from agriculture , fossil fuel production, waste, and other sources. If current emission rates continue then temperature rises will surpass 2.0 °C (3.6 °F) sometime between 2040 and 2070, which

3212-448: The demand for iron-based building products, due mainly to problems of producing steel from alkaline ores. These problems, caused principally by the presence of phosphorus, were solved by Sidney Gilchrist Thomas in 1879. It was not until 1880 that an era of construction based on reliable mild steel began. By that date the quality of steels being produced had become reasonably consistent. The Home Insurance Building , completed in 1885,

3285-454: The direct measurement of atmospheric concentrations and direct and indirect measurement of greenhouse gas emissions . Indirect methods calculate emissions of greenhouse gases based on related metrics such as fossil fuel extraction. There are several different methods of measuring carbon dioxide concentrations in the atmosphere, including infrared analyzing and manometry . Methane and nitrous oxide are measured by other instruments, such as

3358-402: The early 1970s, before the health risks of asbestos fibres were fully understood. The exterior "skin" of the building is anchored to the frame using a variety of construction techniques and following a huge variety of architectural styles . Bricks , stone , reinforced concrete , architectural glass , sheet metal and simply paint have been used to cover the frame to protect the steel from

3431-429: The exact length needed so there is minimal waste. Recycled material can be incorporated into studcast. Recycled steel can be used as raw material for the studs. The concrete can contain recycled aggregate and be made from locally extracted materials. Some manufacturers have 25% or more recycled content. Because each square foot of wall weighs so little, transportation-related energy consumption and pollution are kept to

3504-503: The grain structure of the steel and align its crystalline lattice. It is then passed through precision rollers to achieve the desired frame profiles. The distinctive feature of hot formed frames is their substantial beam thickness and larger dimensions, making them more robust compared to their cold rolled counterparts. This inherent strength makes them particularly well-suited for application in larger structures, as they show minimal deformation when subjected to substantial loads. While it

3577-446: The greenhouse effect, acting in response to other gases as a climate change feedback . Human activities since the beginning of the Industrial Revolution (around 1750) have increased carbon dioxide by over 50% , and methane levels by 150%. Carbon dioxide emissions are causing about three-quarters of global warming , while methane emissions cause most of the rest. The vast majority of carbon dioxide emissions by humans come from

3650-506: The industrial era, human activities have added greenhouse gases to the atmosphere, mainly through the burning of fossil fuels and clearing of forests. The major anthropogenic (human origin) sources of greenhouse gases are carbon dioxide (CO 2 ), nitrous oxide ( N 2 O ), methane and three groups of fluorinated gases ( sulfur hexafluoride ( SF 6 ), hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs, sulphur hexafluoride (SF 6 ), and nitrogen trifluoride (NF 3 )). Though

3723-459: The length of the member) are high, such as in load-bearing construction. Medium-heavy gauges, such as 16 and 18 gauge, are commonly used when there are no axial loads but heavy lateral loads (perpendicular to the member) such as exterior wall studs that need to resist hurricane-force wind loads along coasts. Light gauges, such as 25 gauge, are commonly used where there are no axial loads and very light lateral loads such as in interior construction where

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3796-455: The limited remaining atmospheric carbon budget ." The report commented that the world should focus on broad-based economy-wide transformations and not incremental change. Several technologies remove greenhouse gas emissions from the atmosphere. Most widely analyzed are those that remove carbon dioxide from the atmosphere, either to geologic formations such as bio-energy with carbon capture and storage and carbon dioxide air capture , or to

3869-428: The members serve as framing for demising walls between rooms. The wall finish is anchored to the two flange sides of the stud, which varies from 1 + 1 ⁄ 4 to 3 inches (32 to 76 mm) thick, and the width of web ranges from 1 + 5 ⁄ 8 to 14 inches (41 to 356 mm). Rectangular sections are removed from the web to provide access for electrical wiring. Steel mills produce galvanized sheet steel,

3942-828: The most important contributions to the overall greenhouse effect, without which the average temperature of Earth's surface would be about −18 °C (0 °F), instead of around 15 °C (59 °F). This table also specifies tropospheric ozone , because this gas has a cooling effect in the stratosphere , but a warming influence comparable to nitrous oxide and CFCs in the troposphere . K&T (1997) used 353 ppm CO 2 and calculated 125 W/m total clear-sky greenhouse effect; relied on single atmospheric profile and cloud model. "With Clouds" percentages are from Schmidt (2010) interpretation of K&T (1997). Schmidt (2010) used 1980 climatology with 339 ppm CO 2 and 155 W/m total greenhouse effect; accounted for temporal and 3-D spatial distribution of absorbers. Water vapor

4015-410: The panel until the steel frame is partially embedded. Various methods are used to create composite action between steel and concrete, and add sheer resistance and impact resistance . Steel framing 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

4088-508: The projections of coupled models referenced in the AR5 assessment. A substantial fraction (20–35%) was also projected to remain in the atmosphere for centuries to millennia, where fractional persistence increases with pulse size. Values are relative to year 1750. AR6 reports the effective radiative forcing which includes effects of rapid adjustments in the atmosphere and at the surface. Atmospheric concentrations are determined by

4161-788: The range-resolved infrared differential absorption lidar (DIAL). Greenhouse gases are measured from space such as by the Orbiting Carbon Observatory and through networks of ground stations such as the Integrated Carbon Observation System . The Annual Greenhouse Gas Index (AGGI) is defined by atmospheric scientists at NOAA as the ratio of total direct radiative forcing due to long-lived and well-mixed greenhouse gases for any year for which adequate global measurements exist, to that present in year 1990. These radiative forcing levels are relative to those present in year 1750 (i.e. prior to

4234-584: The reduced consumption specifically of portland cement , whose production emits large quantities of carbon dioxide (CO 2 ), a greenhouse gas . Low mass walls have an additional benefit in high seismic activity zones , where they translate into less force shaking the structure during earthquake events. Studcast has both architectural and structural applications. It has been used in hospitality design , military construction , retail , commercial , industrial, and residential design . Specific applications include: The versatility of architectural precast

4307-605: The same element , they have no asymmetry in the distribution of their electrical charges , and so are almost totally unaffected by infrared thermal radiation, with only an extremely minor effect from collision-induced absorption . A further 0.9% of the atmosphere is made up by argon (Ar), which is monatomic , and so completely transparent to thermal radiation. On the other hand, carbon dioxide (0.04%), methane , nitrous oxide and even less abundant trace gases account for less than 0.1% of Earth's atmosphere, but because their molecules contain atoms of different elements, there

4380-470: The same mass of carbon dioxide over a 20-year time frame. Since the 1980s, greenhouse gas forcing contributions (relative to year 1750) are also estimated with high accuracy using IPCC-recommended expressions derived from radiative transfer models . The concentration of a greenhouse gas is typically measured in parts per million (ppm) or parts per billion (ppb) by volume. A CO 2 concentration of 420 ppm means that 420 out of every million air molecules

4453-404: The soil, the oceans and other waters, or vegetation and other biological systems, reducing the excess to background concentrations. The average time taken to achieve this is the mean lifetime . This can be represented through the following formula, where the lifetime τ {\displaystyle \tau } of an atmospheric species X in a one- box model is the average time that

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4526-413: The spacing is 24 inches (610 mm) on center for all walls except for elevator and staircase wells. Hot Formed frames, also known as hot-rolled steel frames, are engineered from steel that undergoes a complex manufacturing process known as hot rolling. During this procedure, steel members are heated to temperatures above the steel’s recrystallization temperature (1700˚F).This process serves to refine

4599-514: The specific considerations when building using cold-formed steel is that thermal bridging can occur across the wall system between the outside environment and interior conditioned space. Thermal bridging can be protected against by installing a layer of externally fixed insulation along the steel framing – typically referred to as a 'thermal break'. The spacing between studs is typically 16 inches on center for home exterior and interior walls depending on designed loading requirements. In office suites

4672-521: The start of the industrial era ). 1990 is chosen because it is the baseline year for the Kyoto Protocol , and is the publication year of the first IPCC Scientific Assessment of Climate Change . As such, NOAA states that the AGGI "measures the commitment that (global) society has already made to living in a changing climate. It is based on the highest quality atmospheric observations from sites around

4745-418: The table. and Annex III of the 2021 IPCC WG1 Report (years) GWP over time up to year 2022 Year 1750 Year 1998 Year 2005 Year 2011 Year 2019 Mole fractions : μmol/mol = ppm = parts per million (10 ); nmol/mol = ppb = parts per billion (10 ); pmol/mol = ppt = parts per trillion (10 ). The IPCC states that "no single atmospheric lifetime can be given" for CO 2 . This

4818-553: The top of the steel frame as a "form" or corrugated mold, below a thick layer of concrete and steel reinforcing bars . Another popular alternative is a floor of precast concrete flooring units with some form of concrete topping. Often in office buildings, the final floor surface is provided by some form of raised flooring system with the void between the walking surface and the structural floor being used for cables and air handling ducts. The frame needs to be protected from fire because steel softens at high temperature and this can cause

4891-424: The top-of-atmosphere, which causes additional warming, while negative forcing, like from sulfates forming in the atmosphere from sulfur dioxide , leads to cooling. Within the lower atmosphere, greenhouse gases exchange thermal radiation with the surface and limit radiative heat flow away from it, which reduces the overall rate of upward radiative heat transfer. The increased concentration of greenhouse gases

4964-415: The weather. Cold-formed steel frames are also known as lightweight steel framing (LSF). Thin sheets of galvanized steel can be cold formed into steel studs for use as a structural or non-structural building material for both external and partition walls in both residential, commercial and industrial construction projects (pictured). The dimension of the room is established with a horizontal track that

5037-602: The world. It excludes water vapor because changes in its concentrations are calculated as a climate change feedback indirectly caused by changes in other greenhouse gases, as well as ozone, whose concentrations are only modified indirectly by various refrigerants that cause ozone depletion . Some short-lived gases (e.g. carbon monoxide , NOx ) and aerosols (e.g. mineral dust or black carbon ) are also excluded because of limited role and strong variation, along with minor refrigerants and other halogenated gases, which have been mass-produced in smaller quantities than those in

5110-408: The world. Its uncertainty is very low." The natural flows of carbon between the atmosphere, ocean, terrestrial ecosystems , and sediments are fairly balanced; so carbon levels would be roughly stable without human influence. Carbon dioxide is removed from the atmosphere primarily through photosynthesis and enters the terrestrial and oceanic biospheres. Carbon dioxide also dissolves directly from

5183-485: Was initially slow. The first iron-framed building, Ditherington Flax Mill , had been built in 1797, but it was not until the development of the Bessemer process in 1855 that steel production was made efficient enough for steel to be a widely used material. Cheap steels, which had high tensile and compressive strengths and good ductility, were available from about 1870, but wrought and cast iron continued to satisfy most of

5256-774: Was the first to use skeleton frame construction, completely removing the load bearing function of its masonry cladding. In this case the iron columns are merely embedded in the walls, and their load carrying capacity appears to be secondary to the capacity of the masonry, particularly for wind loads. In the United States, the first steel framed building was the Rand McNally Building in Chicago, erected in 1890. The Royal Insurance Building in Liverpool designed by James Francis Doyle in 1895 (erected 1896–1903)

5329-490: Was the first to use a steel frame in the United Kingdom. Greenhouse gas This is an accepted version of this page Greenhouse gases ( GHGs ) are the gases in the atmosphere that raise the surface temperature of planets such as the Earth. What distinguishes them from other gases is that they absorb the wavelengths of radiation that a planet emits , resulting in the greenhouse effect . The Earth

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