Building materialsBuilding materials must have certain structural use.it physical properties. First, they must be able to bear load or weight without permanent deformation. When the load on the structural components, components will deformation, it means rope will be stretching or beam will bend. However, when the load is removed, ropes and beams will return to its original position. This kind of material properties is called elasticity. If material is not elastic, then on removing load deformation exist, repeat the loading and unloading eventually increase deformation to structural lose action.All used in building structure in the materials such as stone, brick, wood, aluminum, reinforced concrete and plastic within a certain range of load performance of flexibility. If loading beyond the scope, two things will happen: brittle and plastic. If it is the former, the material will suddenly destruction; If the latter, in certain load (yield strength) material has begun to yield flow, resulting in destruction. For example, steel, stone material is brittle present plastic. Materials by the damage occurred when the ultimate strength of stress decision.Construction materials and an important characteristic is its stiffness. This feature by elastic modulus decision. Stress (per unit of area, the force) and the strain (per unit length ratio of the deformation) is elastic modulus. Elastic modulus is characterize material under load shape-shifting abilities. For two have the same area and load of the same material. Elastic modulus big materials little deformation. Structure with steel of elastic modulus is pounds per square inch or kg per square centimeter, aluminum, concrete 3 times of ten times, wood 15 times.Masonry. Masonry from natural materials such as stone and artificial materials such as brick, concrete blocks composed. Masonry in ancient times is used. Bricks used in city of Babylon not religious buildings, stone material used in large temples of the Nile valley. The pyramids of Egypt, high 481 feet (147m), is the most spectacular masonry structure. Masonry unit initial without using any binding materials piled up, and modern masonry structure as binder materials. Water mud Modern structure material including stone, red-roast clay brick or tiles, the concrete blocks.Masonry is essentially a pressurized material, it can't sustain tension, ultimate strength concrete-block masonry depends on and mud. Last strength in 1000 to 4,000 pounds per inch (70 to 280 kg per square centimeter) range change, depends on the block and mud bonding situation.Wood. Wood is a kind of the earliest building materials and is a kind of rare tensile performance good natural material. The world find hundreds of wood, and each have different physical properties. Only some use in architectural structures as framework components. In the United States, for example, in over 600 kinds of lumber, only 20 used in structure. These are generally conifers or cork, both because rich and wood easy molding. In the United States, more common in the structure of lumber sort is the loose, spruce and annatto. These timber tensile strength in 50 to 80 pounds per square inch (350 to 5.6 kg per square meter) range. Hardwood initially used as fine wood furniture and interior decoration such as floor.Due to the wood texture characteristics, it along the intensity of transverse texture texture is greater than the intensity. Wood tensile strength,trans-monounsaturated grain compressive strength is particularly big, and it has a lot of flexural strength. These characteristics make it very suitable for structure of the column and beam. Wood, as truss tensile component is invalid, because the truss structures tensile strength depends on component between node, although has produced many USES lumber tensile strength of metal fittings, but it is difficult to design the arrange grain direction of shear strength or tensile strength little relation of components.Steel. Steel is an important structural materials. When compared to the other materials by such as weight, it has high intensity, even if it volumetric weight is lumber ten times. Its elastic modulus is very big, the results under load deformation is small. It can be rolled into many structural forms such as work fonts beam, plate. It can also cast complex style, it also can produce into ropes type used in cable suspension bridge and condole top, production into elevator rope and prestressed concrete in the rods. Steel components are many ways of link together like bolt connection, riveting and welding. Carbon steels are vulnerable to oxidation corrosiontherefore must rely on paint or inserted into the concrete to avoid contact with air. More than steel soon lose strength, so we must set a fire-proof material (usually concrete) in order to increase its refractory ability.Add like silicon or manganese such alloying elements, you'll get tensile strength of 250,000 pounds per square inch (17500 kg/cm2) of high strength steel. These steel on the structure of key parts, such as skyscrapers pillars.Aluminum. When light weight, high strength and corrosion resistance has become an important factor, aluminum became a particularly useful building materials. Because pure aluminum is extremely soft and ductility of, so, the composition of the alloy, such as mn, silicon, zinc and copper must add increase structure required strength. Structural use of aluminium alloy performance of flexibility. Their elastic modulus is steel 1/3, therefore in the same loads deformation is 3 times of steel. Each unit of aluminum alloy is weight steel 1/3. Therefore the same intensities, aluminum alloy component than steel components in weight. Aluminum alloy limit tensile strength variation in 20,000 to 60,000 pounds per square inch (14 to 4,200 kg/cm2) between.Aluminum can fashioned many shapes, it can be extrusion forming strander liang, pull string and stem, rolled into foil and plate. Aluminum component can like steel use the same method, riveting, bolt connection, low strength welded together. Besides being used for architectural framework and prefabrecated house, aluminum also widely used as an window frame and structure curtain box.Concrete. Concrete is water, sand, stone and ordinary Portland cement mixture. Gravel, artificial light stone, and shells were used in natural ShiLiaoChang. Ordinary silicate cement is contains calcium and clay mixtures. In the heating furnace, and then to a fine powder. Concrete strength comes from mixing water farinaceous ordinary Portland cement, then atherosclerosis. In an ideal mixture, concrete by 3/4 volume of sand and stone and 1/4 volume of water mud. The physical characteristics of concrete mixture composition is sensitive to changes, therefore according to strength or contraction design composition ratio to achieve special results. When concrete dump in template, it contains free water, and no need water action of water will evaporate.With concrete sclerosis, it in a certain period of releasing excess water and shrinking. As a result of shrinkage, the fine cracks. In order to minimize the shrinkage crack, concrete sclerosis must protect wet at least five days. Concrete strength increased over time, because the hydration processes will last for years, In fact, 28 days intensity is considered the standard.Concrete under load is elastic deformation. Although its elastic modulus is steel one-tenth, but distortion is same, because its strength also only steel 10. Concrete is essentially a compressive material, its tensile strength can be neglected.Reinforced concrete. Reinforced concrete by placed to undertake in reinforced concrete pulling force. These reinforced in 1/4 inch in diameter (0.64 cm) and 225 inches (5.7 cm) between, the surface has Nick to ensure binding live concrete. Although reinforced concrete in many countries have development, but its discovery should be attributed to a French gardeners, Joseph in 1868 reinforcement strengthening concrete with a cone. The operation is possible, because when a change in temperature, reinforcement and concrete are equal to expansion and contraction. If this is not the case, the temperature changes, the connection between the reinforcement and concrete is destroyed, because the two materials react differently. Reinforced concrete can be pouring into various shapes, for example liang, column, the board and arch. Therefore, it is suitable for construction of special structure. Although most merchandise concrete strength around 6,000 pounds per square inch (4.2 kg/cm2), but the reinforced concrete limit tensile strength than 10,000 pounds per square inch (700 kilograms/cm2) is possible.Plastic. Because of many varieties, high strength, endurance and lightweight, plastic quickly become important structural materials. Plastics are synthetic materials or resin, can be configured to expect any shape and use organic matter for cementing agent. Organic plastic into two categories: thermoset and thermoplastic. Thermosetting plastic when heated through chemical change is strong, once forming, these plastic can no longer be cast. Thermoplastic in high temperature is weak, strong cooling, the former must not generally used for structural plastic material. Although nylon tensile achieves 60,000 pounds per square inch, but most plastics of ultimatestrength in 7000 to 12,000 pounds per square inch (490 to 840 kg/cm2) range.建筑材料建筑材料必须有一定结构上的使用性的物理特性。