狠狠干很很操,久久免费视频国产,九九热视频在线免费观看,日韩在线免费,热99精品,九九精视频,精品亚洲天堂

Lattice columns are used as compression-bending steel structure components, and are mostly used for plant frame columns and independent columns. The cross-sections are generally section steel or steel plates designed with biaxial symmetry or uniaxial symmetry. The components of the lattice system are composed of limbs and binding materials. The limbs mainly bear axial force, and the binding material mainly resists lateral force (relative to the axial direction of the limb). Lattice column binding materials mainly include strips and panels. The structural feature of the lattice column is that the material area is arranged far away from the axis of inertia, which can ensure the bending resistance of the reinforced member under the same axial resistance condition and save material.