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78-505: The throne was built from 1747 to 1751. It was designed by Mirza Baba Shirazi (Naqqash Bashi) and royal stonecutter , Mohammad Ebrahim Esfahani. It consists of 65 marble stone pieces from a mine in Yazd . The throne's supports are carved in the shape of men, women, fairies, and demons. The Royal Balcony of the Marble Throne is said to be built during the reign of Karim Khan Zand , but Karim khan

156-451: A 24-hour period, meaning that this wood does not "absorb" heat and therefore only emits the heat embedded in it. Moreover, white wood not only possesses a lower thermal conductivity than natural wood, and it has better thermal performance than most commercially available insulating materials . The modification of the mesoporous structure of the wood is responsible for the changes in wood performance. White wood can also be put through

234-558: A binding process with adhesives. Wood structural panels are a collection of flat panel products, used extensively in building construction for sheathing, decking, cabinetry and millwork, and furniture. Examples include plywood and oriented strand board (OSB). Non-structural wood-based panels are flat-panel products, used in non-structural construction applications and furniture. Non-structural panels are usually covered with paint, wood veneer, or resin paper in their final form. Examples include fiberboard and particle board . Plywood ,

312-484: A building. It is one of the oldest types of mass timber, being used in warehouse construction during the Industrial Revolution . Like DLT, no chemical adhesives are used, and wood fibers are oriented in the same direction. Engineered wood flooring is a type of flooring product, similar to hardwood flooring, made of layers of wood or wood-based composite laminated together. The floor boards are usually milled with

390-416: A chemical process that replaces light-absorbing compounds, such as lignin , with a transparent polymer. New construction is in high demand due to growing worldwide population. However, the main materials used in new construction are currently steel and concrete . The manufacturing of these materials creates comparatively high emissions of carbon dioxide (CO 2 ) into the atmosphere. Engineered wood has

468-435: A combination of delignification and water shock treatment. This is an emerging technology and is not yet used in industrial processes. However, initial tests show promising advantages in improved mechanical properties, with the molded wood exhibiting strength comparable to some metal alloys. Transparent wood composites are new materials, as of 2020 are made at the laboratory scale, that combines transparency and stiffness via

546-411: A compression process, similar to the process mentioned for densified wood, which increases its mechanical performance compared to natural wood (8.7 times higher in tensile strength and 10 times higher in toughness). The thermal and structural advantages of nanowood make it an attractive material for energy-efficient building construction. However, the changes made in the wood's structural properties, like

624-425: A crane reduces labor, accelerates construction, and allows the masons to precisely and quickly position the blocks. MP stone is defined by four design attributes. MP stone construction has advantages over conventional masonry and concrete construction. Fernand Pouillon pioneered the use of massive precut stone in modern architecture. During the post-war period, his innovative approach to stone construction led to

702-493: A dimensional solid wood joist of a size necessary to do the same task. As of 2004, approximately 81% of all wood light framed floors were framed using I-joists. Mass timber, also known as engineered timber, is a class of large structural wood components for building construction. Mass timber components are made of lumber or veneers bonded with adhesives or mechanical fasteners. Certain types of mass timber, such as nail-laminated timber and glue-laminated timber, have existed for over

780-572: A fine finish on the stone. A drove chisel is used for smoothing off roughly finished stones. Mixing mortar is normally done today with mortar mixers which usually use a rotating drum or rotating paddles to mix the mortar. The masonry trowel is used for the application of the mortar between and around the stones as they are set into place. Filling in the gaps (joints) with mortar is referred to as pointing. Pointing in smaller joints can be accomplished using tuck pointers , pointing trowels , and margin trowels , among other tools. A mason's hammer has

858-417: A good way to learn about stonemasonry also. Those wishing to become stonemasons should have little problem working at heights, possess reasonable hand-eye coordination, be moderately physically fit, and have basic mathematical ability. Most of these things can be developed while learning. The modern stonemason undergoes comprehensive training, both in the classroom and in the working environment. Hands-on skill

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936-501: A group of building materials that can replace concrete assemblies. Typically, engineered wood products are made from the same hardwoods and softwoods used to manufacture lumber . Sawmill scraps and other wood waste can be used for engineered wood composed of wood particles or fibers, but whole logs are usually used for veneers, such as plywood , medium-density fibreboard (MDF), or particle board . Some engineered wood products, like oriented strand board (OSB), can use trees from

1014-448: A high length-to-thickness ratio. Combined with an adhesive, the strands are oriented and formed into a large mat or billet and pressed. LSL and OSL offer good fastener-holding strength and mechanical-connector performance and are commonly used in a variety of applications, such as beams, headers, studs, rim boards, and millwork components. LSL is manufactured from relatively short strands—typically about 1 foot (0.30 m) long—compared to

1092-559: A hundred years. Mass timber enjoyed increasing popularity from 2012 onward, due to growing concern around the sustainability of building materials, and interest in prefabrication, off site construction, and modularization, for which mass timber is well suited. The various types of mass timber share the advantage of faster construction times as the components are manufactured off-site, and pre-finished to exact dimensions for simple on-site fastening. Mass timber has been shown to have structural properties competitive with steel and concrete, opening

1170-415: A large number of nanopores in the cell walls which help reduce temperature change. Delignified wood reflects most incident light and appears white in color. White wood (also known as nanowood ) has high reflection haze, as well as high emissivity in the infrared wavelengths. These two characteristics generate a passive radiative cooling effect, with an average cooling power of 53 W⋅m over

1248-541: A long thin head and is called a Punch Hammer. It would be used with a chisel or splitter for a variety of purposes A walling hammer (catchy hammer) can be used in place of a hammer and chisel or pincher to produce rubble or pinnings or snecks. Stonemasons use a lewis together with a crane or block and tackle to hoist building stones into place. Today power tools such as compressed-air chisels, abrasive spinners, and angle grinders are much used: these save time and money, but are hazardous and require just as much skill as

1326-571: A masonry engineer at a quarry in Fontvieille, to adapt high-precision saws from the timber industry to quarrying and stone sawing. The key technique of massive precut (MP) stone is to cut stone ashlars to precise dimensions that match the architect's plan such that the stones can be dropped into place by crane for rapid construction. The blocks may be numbered so that the masons can follow the plan procedurally. The use of massive blocks reduces costs by minimizing sawing and fixer-masonry costs. The use of

1404-500: A mechanical hot press to compress wood fibers, sometimes in combination with chemical modification of the wood. These processes have been shown to increase the density by a factor of three. This increase in density is expected to enhance the strength and stiffness of the wood by a proportional amount. Studies published in 2018 combined chemical processes with traditional mechanical hot press methods. These chemical processes break down lignin and hemicellulose that are found naturally in

1482-440: A model code that forms the basis of many North American building codes , adopted new provisions in the 2021 code cycle that permit mass timber to be used in high-rise construction up to 18 stories. Cross-laminated timber (CLT) is a versatile multi-layered panel made of lumber. Each layer of boards is placed perpendicular to adjacent layers for increased rigidity and strength. It is relatively new and gaining popularity within

1560-463: A resin binder, and forming panels by applying high temperature and pressure. MDF is used in non-structural applications. Particle board is manufactured from wood chips, sawmill shavings, or even sawdust , and a synthetic resin or another suitable binder, which is pressed and extruded. Research published in 2017 showed that durable particle board can be produced from agricultural waste products, such as rice husk or guinea corn husk. Particleboard

1638-572: A simple ‘quality assurance’ system. The Renaissance saw stonemasonry return to the prominence and sophistication of the Classical age . The rise of the humanist philosophy gave people the ambition to create marvelous works of art. The centre stage for the Renaissance would prove to be Italy, where Italian city-states such as Florence erected great structures, including the Florence Cathedral ,

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1716-530: A single piece, but drill limitations and other considerations mean it is typically an assembly of multiple components with mortar between pieces. PT stone has been used in both vertical columns (posts), and in horizontal beams (lintels). It has also been used in more unusual engineering applications: arch stabilization, flexible foot bridges, and cantilevered sculptures. Tensioned stone has a close affiliation with massive precut stone as two central techniques of modern stonemasonry . "Post-tensioned stone increases

1794-567: A tongue-and-groove profile on the edges for consistent joinery between boards. The lamella is the face layer of the wood that is visible when installed. Typically, it is a sawn piece of timber. The timber can be cut in three different styles: flat-sawn, quarter-sawn, and rift-sawn. Techniques have been introduced in the field of engineered wood including transformation of natural wood in laboratories through chemical and/or physical treatments to achieve tailored mechanical, optical, thermal, and conduction properties. Densified wood can be made by using

1872-572: A wide variety of tools to handle and shape stone blocks ( ashlar ) and slabs into finished articles. The basic tools for shaping the stone are a mallet , chisels , and a metal straight edge . With these one can make a flat surface – the basis of all stonemasonry. Chisels come in a variety of sizes and shapes, dependent upon the function for which they are being used and have many different names depending on locality. There are different chisels for different materials and sizes of material being worked, for removing large amounts of material and for putting

1950-506: A wood structural panel, is sometimes called the original engineered wood product. Plywood is manufactured from sheets of cross-laminated veneer and bonded under heat and pressure with durable, moisture-resistant adhesives. By alternating the grain direction of the veneers from layer to layer, or "cross-orienting", panel strength and stiffness in both directions are maximized. Other structural wood panels include oriented strand boards and structural composite panels. Oriented strand board (OSB)

2028-507: Is structural composites . For example, fiber cement siding is made of cement and wood fiber, while cement board is a low-density cement panel, often with added resin, faced with fiberglass mesh . While formaldehyde is an essential ingredient of cellular metabolism in mammals , studies have linked prolonged inhalation of formaldehyde gases to cancer. Engineered wood composites have been found to emit potentially harmful amounts of formaldehyde gas in two ways: unreacted free formaldehyde and

2106-410: Is a stub . You can help Misplaced Pages by expanding it . Stonemasonry Stonemasonry or stonecraft is the creation of buildings , structures, and sculpture using stone as the primary material. Stonemasonry is the craft of shaping and arranging stones, often together with mortar and even the ancient lime mortar , to wall or cover formed structures. The basic tools, methods and skills of

2184-585: Is a class of materials made with layers of veneers, strands, or flakes bonded with adhesives. Unlike wood structural panels, structural composite lumber products generally have all grain fibers oriented in the same direction. The SCL family of engineered wood products are commonly used in the same structural applications as conventional sawn lumber and timber, including rafters, headers, beams, joists, rim boards, studs, and columns. SCL products have higher dimensional stability and increased strength compared to conventional lumber products. Laminated veneer lumber (LVL)

2262-521: Is a modern method of building with load-bearing stone. Precut stone is a DFMA construction method that uses large machine-cut stone blocks with precisely defined dimensions to rapidly assemble buildings in which stone is used as a major or the primary load-bearing material. Massive precut stone construction was originally developed by Fernand Pouillon in postwar period who referred to the method as "pierre de taille" or "pré-taille" stone. It became possible through innovations by Pouillon and Paul Marcerou,

2340-461: Is a much more effective additive. Phenol forms a water-resistant bond with formaldehyde that will not degrade in moist environments. PF resins have not been found to pose significant health risks due to formaldehyde emissions. While PF is an excellent adhesive, the engineered wood industry has started to shift toward polyurethane binders like pMDI to achieve even greater water resistance, strength, and process efficiency. pMDIs are also used extensively in

2418-422: Is a wood structural panel manufactured from rectangular-shaped strands of wood that are oriented lengthwise and then arranged in layers, laid up into mats, and bonded together with moisture-resistant, heat-cured adhesives. The individual layers can be cross-oriented to provide strength and stiffness to the panel. Similar to plywood, most OSB panels are delivered with more strength in one direction. The wood strands in

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2496-511: Is a wood-on-wood timber. The biggest benefit of this method is that no glue or metal is needed, thus eliminating VOCs (such as formaldehyde ) associated with wood adhesives used in most other engineered timbers. Similar to CLT , DLT uses a cross laminated pattern with softwoods , but instead of wood adhesives to fix lumbers in place, holes are drilled vertically or in a 45° angle, and 15-20mm dowels made of dry hardwood or densified wood (such as thermal-compressed ) are placed between

2574-455: Is also possible to impregnate wood chips to produce molded pressed wood components. Removing lignin from wood has several other applications, apart from providing structural advantages. Delignification alters the mechanical, thermal, optical, fluidic and ionic properties and functions of the natural wood and is an effective approach to regulating its thermal properties, as it removes the thermally conductive lignin component, while generating

2652-429: Is cheaper, denser, and more uniform than conventional wood and plywood and is substituted for them when the cost is more important than strength and appearance. A major disadvantage of particleboard is that it is very prone to expansion and discoloration due to moisture, particularly when it is not covered with paint or another sealer. Particle board is used in non-structural applications. Structural composite lumber (SCL)

2730-401: Is complemented by an intimate knowledge of each stone type, its application, and best uses, and how to work and fix each stone in place. The mason may be skilled and competent to carry out one or all of the various branches of stonemasonry. In some areas, the trend is towards specialization, in other areas towards adaptability. Today's stonemasons undergo training that is quite comprehensive and

2808-751: Is done both in the work environment and in the classroom. It isn't enough to have hands-on skills only. One must also have knowledge of the types of stones as well as its best uses and how to work it as well as how to fix it in place. Stonemasons use all types of natural stone: igneous , metamorphic and sedimentary ; while some also use artificial stone as well. Many of the world's most famous buildings have been built of sedimentary stone, from Durham Cathedral to St Peter's in Rome . There are two main types of sedimentary stone used in masonry work, limestones and sandstones . Examples of limestones include Bath and Portland stone . Yorkstone and Sydney sandstone are

2886-519: Is known to have even refused the title king, and preferred to sit on a carpet rather than a throne so his ownership of the Marble throne is unlikely. It was changed several times during the Qajar period. The twin stone columns of the balcony were transferred to Tehran, by the order of Agha Mohammad Khan , from Shiraz . The Sun Throne was probably modelled after it. The throne is modeled after Persepolis where

2964-551: Is one of the earliest trades in civilization 's history. During the time of the Neolithic Revolution and domestication of non-human animals, people learned how to use fire to create quicklime , plasters , and mortars. They used these to fashion homes for themselves with mud, straw or stone, and masonry was born. The Ancients heavily relied on the stonemason to build the most impressive and long-lasting monuments to their civilizations. The Egyptians built their pyramids ,

3042-543: Is produced by bonding thin wood veneers together in a large billet, similar to plywood. The grain of all veneers in the LVL billet is parallel to the long direction (unlike plywood). The resulting product features enhanced mechanical properties and dimensional stability that offer a broader range in product width, depth, and length than conventional lumber. Parallel-strand lumber (PSL) consists of long veneer strands laid in parallel formation and bonded together with an adhesive to form

3120-474: Is typically made out of man-made wood due to its low manufacturing costs and its low weight. There are a wide variety of engineered wood products for both structural and non-structural applications. This list is not comprehensive, and is intended to help categorize and distinguish between different types of engineered wood. Wood-based panels are made from fibres, flakes, particles, veneers, chips, sawdust, slabs, wood powder, strands, or other wood derivate through

3198-650: The Fountain of Neptune , and the Laurentian Library , which was planned and built by Michelangelo Buonarroti , a famous sculptor of the Renaissance. When Europeans settled the Americas, they brought the stonemasonry techniques of their respective homelands with them. Settlers used what materials were available, and in some areas, stone was the material of choice. In the first waves, building mimicked that of Europe, to eventually be replaced by unique architecture later on. In

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3276-973: The Parthenon , Stonehenge , the Great Wall of China , the Mesoamerican pyramids , Chartres Cathedral , and the Stari Most . While stone was important traditionally, it fell out of use in the modern era, in favor of brick and steel-reinforced concrete. This is despite the advantages of stone over concrete. Those advantages include: Modern stonemasonry is in the process of reinventing itself for automation, modern load-bearing stone construction, innovative reinforcement techniques , and integration with other sustainable materials, like engineered wood . Stone has been used in construction for thousands of years, in many contexts. Listed below are six types of classical stonemasonry techniques, some of which still see widespread use. In

3354-537: The Renaissance , the stonemason's guild admitted members who were not stonemasons, and eventually evolved into the Society of Freemasonry ; fraternal groups which observe the traditional culture of stonemasons but are not typically involved in modern construction projects. A medieval stonemason would often carve a personal symbol onto their block to differentiate their work from that of other stonemasons. This also provided

3432-435: The guild , gave rise to three classes of stonemasons: apprentices , journeymen , and master masons . Apprentices were indentured to their masters as the price for their training, journeymen were qualified craftsmen who were paid by the day, and master masons were considered freemen who could travel as they wished to work on the projects of the patrons and could operate as self-employed craftsmen and train apprentices. During

3510-438: The poplar family, a common but non-structural species. Alternatively, it is also possible to manufacture similar engineered bamboo from bamboo; and similar engineered cellulosic products from other lignin -containing materials such as rye straw, wheat straw, rice straw, hemp stalks, kenaf stalks, or sugar cane residue , in which case they contain no actual wood but rather vegetable fibers . Flat-pack furniture

3588-561: The 2-to-8-foot-long (0.61–2.44 m) strands used in PSL. The length-to-thickness ratio of strands is about 150 for LSL and 75 for OSL. I-joists are "Ɪ"-shaped structural members designed for use in floor and roof construction. An I-joist consists of top and bottom flanges of various widths united with webs of various depths. The flanges resist common bending stresses, and the web provides shear performance. I-joists are designed to carry heavy loads over long distances while using less lumber than

3666-420: The 20th century, stonemasonry saw its most radical changes in the way the work is accomplished. Prior to the first half of the century, most heavy work was executed by draft animals or human muscle power. With the arrival of the internal combustion engine , many of these hard aspects of the trade have been made simpler and easier. Cranes and forklifts have made moving and laying heavy stones relatively easy for

3744-624: The banker mason have existed as a trade for thousands of years. It is one of the oldest activities and professions in human history. Many of the long-lasting, ancient shelters , temples , monuments , artifacts , fortifications , roads , bridges , and entire cities were built of stone. Famous works of stonemasonry include Göbekli Tepe , the Egyptian pyramids , the Taj Mahal , Cusco 's Incan Wall, Taqwesan , Easter Island 's statues , Angkor Wat , Borobudur , Tihuanaco , Tenochtitlan , Persepolis ,

3822-601: The biogenic carbon from a wood product can only be included as a negative input (i.e. carbon sequestration) when the wood product originated in a sustainably managed forest. This generally means that wood needs to be FSC or SFI-certified to qualify as carbon sequestering. Engineered wood products are used in a variety of ways, often in applications similar to solid wood products: Advantages by product type: Engineered wood products may be preferred over solid wood in some applications due to certain comparative advantages: Disadvantages by product type: When compared to solid wood

3900-585: The case of cross-laminated timber (CLT) can be of any thickness from a few inches to 16 inches (410 mm) or more. These products are engineered to precise design specifications, which are tested to meet national or international standards and provide uniformity and predictability in their structural performance. Engineered wood products are used in a variety of applications, from home construction to commercial buildings to industrial products. The products can be used for joists and beams that replace steel in many building projects. The term mass timber describes

3978-628: The chemical decomposition of resin adhesives. When excessive amounts of formaldehyde are added to a process, the surplus will not have any additive to bond with and may seep from the wood product over time. Cheap urea-formaldehyde (UF) adhesives are largely responsible for degraded resin emissions. Moisture degrades the weak UF molecules, resulting in potentially harmful formaldehyde emissions. McLube offers release agents and platen sealers designed for those manufacturers who use reduced-formaldehyde UF and melamine-formaldehyde adhesives. Many OSB and plywood manufacturers use phenol-formaldehyde (PF) because phenol

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4056-617: The civilizations of Central America had their step pyramids , the Persians their palaces, the Greeks their temples, and the Romans their public works and wonders (See Roman Architecture ). People of the Indus Valley Civilization , such as at Dholavira made entire cities characterized by stone architecture. Among the famous ancient stonemasons is Sophroniscus , the father of Socrates , who

4134-508: The construction industry as it can be used for long spans and all assemblies, e.g. floors, walls, or roofs. Glued laminated timber (glulam) is composed of several layers of dimensional timber glued together with moisture-resistant adhesives, creating a large, strong, structural member that can be used as vertical columns or horizontal beams. Glulam can also be produced in curved shapes, offering extensive design flexibility. Dowel laminated timber (DLT), sometimes referred to as Brettstapel ,

4212-411: The development of numerous noteworthy projects, with a particular focus on housing. Throughout his long career, Pouillon played a crucial role in the development and popularization of massive precut stone construction techniques. His pioneering work laid the foundation for subsequent architects to build upon and innovate, leading to the resurgence and expansion of this construction method in the 2020s, with

4290-444: The door for applications of densified wood in situations where regular strength wood would fail. Environmentally, wood requires significantly less carbon dioxide to produce than steel. Synthetic resin densified wood is resin-impregnated densified wood, also known as compreg . Usually phenolic resin is used as impregnation resin to impregnate and laminate plywood layers. Sometimes layers are not impregnated before lamination. It

4368-400: The end of its lifecycle absorbs around 582 kg of CO 2 /m , while reinforced concrete emits 458 kg CO 2 /m and steel 12.087 kg CO 2 /m . There is not a strong consensus for measuring the carbon sequestration potential of wood. In life-cycle assessment, sequestered carbon is sometimes called biogenic carbon. ISO 21930, a standard that governs life cycle assessment, requires

4446-437: The experience of the tradesmen, and college work where apprentices are given an overall experience of the building, hewing and theory work involved in masonry. In some areas, colleges offer courses which teach not only the manual skills but also related fields such as drafting and blueprint reading or construction conservation. Electronic Stonemasonry training resources enhance traditional delivery techniques. Hands-on workshops are

4524-845: The failure load of stone in bending, but also the stiffness of a structure by reducing joint cracking. This method of construction is widely used for concrete structures, but the advantages of using similar techniques with stone are only just being realised". Stone has great compressive strength, so is ideal in compressive structures like stone arches . However, it has relatively weak flexural strength (compared to steel or wood), so in isolation cannot be safely used in wide spans under tension. For concrete, this problem has been long solved: in addition to conventional tensile reinforcement, engineers developed prestressed concrete methods starting around 1888. Such tension-reinforced concrete applications combine compressive strength with pre-stressed tensile compression for combined strength much greater than either of

4602-468: The finished structural section. The length-to-thickness ratio of strands in PSL is about 300. A strong, consistent material, it has a high load-carrying ability and is resistant to seasoning stresses so it is well suited for use as beams and columns for post and beam construction, and for beams, headers, and lintels for light framing construction. Laminated strand lumber (LSL) and oriented strand lumber (OSL) are manufactured from flaked wood strands that have

4680-457: The following disadvantages are prevalent: Plywood and OSB typically have a density of 560–640 kg/m (35–40 lb/cu ft). For example, 9.5 mm ( 3 ⁄ 8  in) plywood sheathing or OSB sheathing typically has a surface density of 4.9–5.9 kg/m (1–1.2 lb/sq ft). Many other engineered woods have densities much higher than OSB. The types of adhesives used in engineered wood include: A more inclusive term

4758-544: The hand tools that they augment. But many of the basic tools of stonemasonry have remained virtually the same throughout vast amounts of time, even thousands of years, for instance when comparing chisels that can be bought today with chisels found at the pyramids of Giza the common sizes and shapes are virtually unchanged. Traditionally medieval stonemasons served a seven-year apprenticeship . A similar system still operates today. A modern apprenticeship lasts three years. This combines on-site learning through personal experience,

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4836-545: The increase in structural porosity and the partially isolated cellulose nanofibrils, damage the material's mechanical robustness. To deal with this issue, several strategies have been proposed, with one being to further densify the structure, and another to use cross-linking . Other suggestions include hybridizing natural wood with other organic particles and polymers to enhance its thermal insulation performance. Using similar chemical modification techniques to chemically densified wood, wood can be made extremely moldable using

4914-408: The individual components, and have been in wide use for decades. As for concrete, post-tensioning maintains stone in compression, thereby increasing its strength. Post-tensioning is achieved steel tendons either threaded through ducts within the stone elements or along their surface. Once the stone components are in place, the tendons are tensioned using hydraulic jacks, and the force is transferred to

4992-595: The legs are made in human shapes. In his book, "The History of Buildings in the Royal Citadel of Tehran", Yahya Zoka describes the construction of this Takht: "As it was impossible to carry Tavus and Naderi Takhts, this Takht was made, modeled after Solomon the Prophet’s Takht who was the king of the Jews and was in possession of great power. [thus], as Fat′h-Ali Shah was compared to him as for his wealth and power, this throne

5070-505: The lumbers. As the hardwood dowel absorbs moisture from the softwood to reach an equilibrium moisture content, it expands into the surrounding wood, creating a connection and 'locking' them together through friction. The dowels can be dried (such as through a kiln ) prior to fitting, to maximize their expansion. Nail laminated timber (NLT) is a mass timber product that consists of parallel boards fastened with nails. It can be used to create floors, roofs, walls, and elevator shafts within

5148-498: The modern era, stone has been largely relegated as a cosmetic element of buildings, often used as decorative cladding on steel-reinforced concrete . This is despite its wide historical use in large compressive structures: 50-m bridges and colosseums in Roman times, ~65-m tall cathedrals since the middle ages , and 12-story apartment buildings built in the 1690s. Massive precut stone is also known as "prefabricated", or "pre-sized" stone

5226-515: The most commonly used sandstone. Categories: Engineered wood Engineered wood , also called mass timber , composite wood , man-made wood , or manufactured board , includes a range of derivative wood products which are manufactured by binding or fixing the strands, particles, fibres, or veneers or boards of wood, together with adhesives , or other methods of fixation to form composite material . The panels vary in size but can range upwards of 64 by 8 feet (19.5 by 2.4 m) and in

5304-702: The outermost layer on each side of the board are normally aligned into the strongest direction of the board. Arrows on the product will often identify the strongest direction of the board (the height, or longest dimension, in most cases). Produced in huge, continuous mats, OSB is a solid panel product of consistent quality with no laps, gaps, or voids. OSB is delivered in various dimensions, strengths, and levels of water resistance. OSB and plywood are often used interchangeably in building construction. Medium-density fibreboard (MDF) and high-density fibreboard ( hardboard or HDF) are made by breaking down hardwood or softwood residuals into wood fibers, combining them with wax and

5382-475: The possibility to build large, tall buildings out of wood. Extensive testing has demonstrated the natural fire resistance properties of mass timber – primarily due the creation of a char layer around a column or beam which prevents fire from reaching the inner layers of wood. In recognition of the proven structural and fire performance of mass timber, the International Building Code ,

5460-406: The potential to reduce carbon emissions if it replaces steel and/or concrete in the construction of buildings. In 2014, steel and cement production accounted for about 1320 megatonnnes (Mt) CO 2 and 1740 Mt CO 2 respectively, which made up about 9% of global CO 2 emissions that year. In a study that did not take the carbon sequestration potential of engineered wood into account, it

5538-492: The production of rigid polyurethane foams and insulators for refrigeration. pMDIs outperform other resin adhesives, but they are notoriously difficult to release and cause buildup on tooling surfaces. Some engineered wood products, such as DLT, NLT, and some brands of CLT, can be assembled without the use of adhesives using mechanical fasteners or joinery. These can range from profiled interlocking jointed boards, proprietary metal fixings, nails or timber dowels. Throughout

5616-410: The rise of interest in low-carbon durable construction. Post-tensioned stone is a high-performance composite construction material: stone held in compression with tension elements. The tension elements can be connected to the outside of the stone, but more typically uses tendons threaded internally through a duct formed from aligned drilled holes. Post-tensioned stone ("PT stone") could consist of

5694-523: The stone through anchorages located at the ends of the tendons. The tensioning process imparts a compressive force to the stone, which improves its capacity to resist tensile stresses that could otherwise cause cracking or failure. Stone is 'natural precast concrete' so only needs to be cut (and strength tested) and post-tensioned prior to use in construction. Compared to concrete and steel, post-tensioned stone production has dramatically lower energy costs, with concomitant lower carbon emissions. Stonemasonry

5772-439: The stonemasons. Motor powered mortar mixers have saved much in time and energy as well. Compressed-air powered tools have made working of stone less time-intensive. Petrol and electric-powered abrasive saws can cut through stone much faster and with more precision than chiseling alone. Cemented carbide -tipped chisels can stand up to much more abuse than the steel and iron chisels made by blacksmiths of old. Stonemasons use

5850-471: The wood. Following dissolution, the cellulose strands that remain are mechanically hot compressed. Compared to the three-fold increase in strength observed from hot pressing alone, chemically processed wood has been shown to yield an 11-fold improvement. This extra strength comes from hydrogen bonds formed between the aligned cellulose nanofibers. The densified wood possessed mechanical strength properties on par with steel used in building construction, opening

5928-666: Was a stone-cutter. Castle building was an entire industry for the medieval stonemasons. When the Western Roman Empire fell, building in dressed stone decreased in much of Western Europe , and there was a resulting increase in timber-based construction. Stonework experienced a resurgence in the 9th and 10th centuries in Europe, and by the 12th-century religious fervour resulted in the construction of thousands of impressive churches and cathedrals in stone across Western Europe. Medieval stonemasons' skills were in high demand, and members of

6006-410: Was found that roughly 50 Mt CO 2 e (carbon dioxide equivalent ) could be eliminated by 2050 with the full uptake of a hybrid construction system utilizing engineered wood and steel. When considering the added effects that carbon sequestration can have over the lifetime of the material, the emissions reductions of engineered wood is even more substantial, as laminated wood that is not incinerated at

6084-485: Was named Solomon’s Takht after the original throne of Solomon which is said to have been carried in the sky and flown by genies and fairies, and would land to the wish of Solomon. After the throne was put in terrace, the terrace was given the name Takht-e Marmar''. [REDACTED] Media related to Marble Throne at Wikimedia Commons 35°40′49″N 51°25′14″E  /  35.6803°N 51.4205°E  / 35.6803; 51.4205 This Iran -related article

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