CLT panels, which are industrial wood materials, are generally 3, 5, 7 or more layered, with the fiber directions of solid wood elements opposite to each other (usually 90°), at least 0.6 N / mm2 with glue on their wide surfaces and in some cases narrow surfaces. pressure bonded, durable, dimensional stability and rigid elements.

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The first use of cross-laminated wood, defined by various abbreviations such as CLT, KLH, BSP, X-LAM and similar in the world, started in Switzerland in the early 1990s. The use of cross-laminated wood technology, which was developed in Austria in 1996 with the efforts of industry and academic research, started to become widespread in the early 2000s. This development has led to the rearrangement of wooden building construction regulations in Europe with the effect of green building approaches. Wooden structures are built in Europe with the Eurocode 5 standard.(1)

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The difference between cross laminated wood and glued laminated wood is that the layers are placed in opposite directions. In glued-laminated wood, the timbers are glued together in such a way that the fibers are parallel to each other. (2) In the factory, the opening of the gaps on the panel elements, sizing and shaping processes are carried out. CNC (computer numerical control) technology is used in the cutting and / or joining of the panels, completely adhering to the designed cutting plans. Panel elements prepared by determining the dimensions according to the project are delivered just before the required time according to the construction site schedule. In a short construction period at the construction site, they are assembled by expert wooden construction companies with the help of cranes.

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Bearing and non-bearing structural elements can be produced from CLT material. Wide openings can be passed with these panel elements. In addition, it can be easily integrated with steel, reinforced concrete and wooden frame systems. They can be used as carriers even if the panels have window and door openings. CLT wall panels are also resistant to dynamic loads. Italy's Trees and Timber Research Institute (CNR-IVALSA) conducted tests in 2009 on two building samples produced with CLT panels in Japan, which has the world's largest vibration table. As a result of these tests, it was determined that CLT structures responded very well to earthquake forces. (3) In addition, in the common walls and assembly tests of CLT panels made by Canada's FBInnovation institution, it was concluded that the wall panels had very good earthquake performances in mounting the wall panels to the flooring with brackets and short screws. (4) The surface properties of CLT panels can be coated or uncoated. In principle, CLT panels can also be combined with all commercially available building materials. In addition to the use of many different insulation materials, different facade coating materials or plaster can be applied. The physical and structural properties of the building such as sound insulation, heat insulation, air tightness or fire protection are evaluated on the basis of the relevant project. It has been observed that it is more resistant to fire than steel and reinforced concrete. Increasing the number of layers and layer thicknesses of the panels used as wall, floor and roof elements and covering their surfaces with gypsum panels increase their resistance to fire. Depending on the thickness and number of layers of the CLT panels, the sound insulation properties also change.