[tau] × Ⅰ× d ÷ s =105×189× 7.5 =148837.5n =148.8375kn =15/kloc-. That is to say, I-beam with model 22a can bear the weight of 2,759 kilograms, about 2.76 tons. In practical application, there should be a certain dynamic load coefficient, that is, 1.25, 2.76÷ 1.25 = 2.2 1 ton, that is. Other models are also calculated in this way. Note that the allowable normal stress and allowable shear stress are different when Q235 and Q345 are used, and the above is calculated according to Q235.