F。__临界力 单位N;E ——材料的弹性模量 单位 Gpa，对槽钢材

F. __critical force unit N; <br>E - elastic modulus unit Gpa of the material, 205GPa for channel steel; <br>I - moment of inertia unit cm*, 1369.9cm* for No. 18 channel steel; 1__ rack height unit m. <br>In the actual working frame, it is only affected by the support force, so just check the support stress of the frame. The frame has the smallest area at the connection, that is, it belongs to the dangerous section

F。__ Critical force, N;<br>E - elastic modulus of material, GPA, 205gpa for channel steel;<br>I -- moment of inertia, unit: cm *, 1369.9cm * for 18 channel steel; 1__ Rack height in M.<br>In the actual work, the rack is only affected by the support force, so just check the support stress of the rack. The area of the rack at the connection is the smallest, that is, it belongs to the dangerous section

F。 _ _ critical force unit n; E —— the unit of elastic modulus of the material is Gpa, which is 205GPa for channel steel materials; I-moment of inertia unit cm*, 1369.9cm* for No.18 channel steel; 1__ Rack height unit m. In practice, the working frame is only affected by the supporting force, so it is only necessary to check the supporting stress of the frame. The area at the joint of the racks is the smallest, which is a dangerous section.