What do you mean by the upper and lower iron and iron in the building?

This is a local saying: the upper iron refers to the upper steel bar, and the lower iron refers to the bottom steel bar. The steel bars in reinforced concrete structures can be divided into the following types according to their functions:

Stress bar-a steel bar that bears tensile stress and compressive stress. Stirrup-bear part of diagonal tensile stress and fix the position of reinforced bar. Used for beams and columns. Erection of steel bars-used to fix the position of steel hoop in the beam and form the steel skeleton in the beam.

Distributed steel bars-used for roof panels and floors, arranged vertically with the stressed steel bars of the plates, which transfer the bearing weight to the stressed steel bars evenly, fix the position of the stressed steel bars, and resist the temperature deformation caused by thermal expansion and contraction. Others —— structural steel bars configured due to structural requirements of members or construction and installation needs. Such as waist tendons, embedded anchor tendons, prestressed tendons, rings, etc.

Extended data:

Black and nonferrous metal materials for building and their composites with other materials are collectively referred to. Metal materials for building are one of the four major materials (steel, cement concrete, wood and plastic) that constitute the material foundation of civil engineering.

In the iron and steel circulation industry, unless otherwise specified, construction steel generally refers to the largest amount of wire and rebar in construction steel. In view of this elite talent, which is also the most scarce in China at present, there is the steel talent network, which is a professional steel industry talent recruitment and job search website.

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