Steel structure lateral inspection "z15" what does that mean?
Steel structure: one of the main structural types of steel structures. It is one of the common structural forms in modern architectural engineering. China was the earliest country to make load-bearing structures with iron. The steel structure project is mainly made of steel. As far back as the Qin Dynasty (246-219 BC), iron had been used as a simple load-bearing structure, while western countries began to use metal bearing structures in seventeenth Century. In the 3-6 century, smart and hard-working people China with chains built iron chain suspension bridge, the famous Sichuan Luding Dadu River Bridge, Jiangqiao Yunnan yuan and Guizhou plate Jiangqiao are China's early iron body bearing structure example. Although China's early iron structure in the remarkable achievements, but because of more than 2000 years of feudal system of bondage, science is underdeveloped, so temporarily stay at the level of iron buildings. It was not until the late nineteenth Century that China began to adopt modern steel structure. After the founding of new China, the application of steel structure has been greatly developed, both in quantity and quality, far more than in the past.
In general, thick steel plate is easy to produce lamellar tearing, because the thicker the steel plate, the more non-metallic inclusion defects, and the thicker the weld, the greater the welding stress and deformation. To solve this problem, it is better to use Z to steel. This kind of steel plate is on the basis of a certain structural steel (called parent steel). After special treatment and processing, the content of sulfur is less than 1/5 of the general steel, and the shrinkage of the section is more than 15%. The mechanical properties of steel plates in the thickness direction (mainly ductility) are called Z properties. The Z properties of steel plates can be obtained by tensile tests of specimens, usually measured by cross-sectional shrinkage. China's production of Z steel plate to mark is in the parent class followed by Z to steel steel plate Z15, Z25, Z35 grade mark, the number after the Z word for section shrinkage index (%).
