发布时间:2019-08-02 18:27:15
钢管截面积 (S) = 27 x 27 x π/4 - (27 - 2 x 3.5) x (27 - 2 x 3.5) x π/4 = 258.4(mm²) =2.584 x 10的-4次方(m²)
钢管密度取ρ = 7.85t/m³
m = ρ x V = ρ x S x l
则: l = m/(ρ x S ) = 0.54/7.85/(2.584 x 10的-4次方) = 266(米)