12/07/2011

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Getting To Work On Wood Mechanical properties of wood mechanical strength of wood depends on many factors: species, structure, bulk density, temperature, humidity, etc. The voltage corresponding to the maximum load is tensile strength. The elastic modulus of wood along the grain, regardless of the breed it is taken in determining the deformation of structures that are protected from moisture and heat and are under the influence of constant and temporary loads E = 100 000 kg/cm2. With increased humidity and temperature "under the influence on the design of only a constant load value of the modulus of elasticity is taken as the product of the above values for the following factors: the short-term wetting of wood, with subsequent drying - 0.85, established under the influence of air temperature in the range of 35 to 50 (for example, in manufacturing plants), as well as the impact constant load - 0.80. The heterogeneity of the structure of wood and its relation to the properties of the various factors make it difficult to study its mechanical properties. A significant factor in the mechanical testing of wood is the impact of loading rate. The faster rising load, the greater is the tensile strength. On the other hand, this limit is reduced under long-term loads. At keeping the sample under load there is a gradual increase in strain, which eventually stopped (attenuated) when the load is not (over a certain limit. When the load is removed part of the deformation disappears and the the other is gradually reduced (attenuated). This phenomenon is called the elastic aftereffect, and the load limit, beyond which the phenomenon is not observed, called the limit of long-term strength of wood. Getting Started work on wood Wood - a unique material. It is very easy to process. In addition, it is durable and very lightweight...
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Masonry Solution Rules for proper performance of face brick lining in this article you will find answers to questions such as what the solution should be chosen when the veneer face brick cottage, how to correctly perform masonry work and seams, what mistakes to avoid, etc. Storage of facing brick on the building site must be stored in a dry place, protected from the pollution solution, resin, concrete and other substances that are difficult or impossible to make to correct spot. Implementation of the solution choice of solution depends on the properties of brick, water absorption of bricks. It is best to use ready-made brick solutions called "two in one", while acting as a filler weld. In deciding to prepare a solution on their own are encouraged to: use a cement brand PC 500 with no additives, use sand and water, containing water-soluble salts, use the "hard" solution, avoiding excessive dilution with water (the consistency of wet land) to use for laying freshly prepared solution, is strictly prohibited apply lime. Masonry work during masonry work, always use the bricks from different trays at least three - this will allow you to avoid such unpleasant things as "spot" of another color on the background of the brickwork. Do not carry out masonry work in the rain and cold. Do not allow the leakage of the solution of the seams on the front surface of the wall. Do not allow freezing of the unfinished masonry: the impossibility of erecting the roof before frost - cover necessarily erected walls for the winter ruberoydom or foil to prevent water from entering the brick and masonry joints in zamokaniya. For the erection of fences is recommended to use fine blocks. New folded wall within 14 days Protect from wetting, covering the waterproof film. Perform welds and seams...

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