钢结构课程设计(单层工业厂房)

minA = 26.127 * 103 0.394 * 13.74 * 102 = 48.3 N/mm2 < f =215 N/mm2Р 满足要求。Р6、斜腹杆4-8,N4-8= -14.936 KN,Р lox= 277.8 cm, loy= 347.2 cm。Р选用2L 70 x 5 角钢,A = 2 * 6.87=13.74cm2, ix=2.16cm, iy=3.09cmР长细比:λx = loxix = 277.82.16 = 128.6 < [λ] = 150 Р λy = loyiy = 347.23.09 = 113.1 < [λ] = 150Р λz = ξ bt = 3.9 x 705 = 54.6Рλy>λz,λyz = λy[1+0.16 (λzλy)2] =113.1*[1+0.16 (54.6113.1)2] =117.3Р查表得φx = 0.394 φyz = 0.432Рσ= NφminA = 14.936 * 103 0.394 * 13.74 * 102 = 27.6 N/mm2 < f =215 N/mm2Р 满足要求。Р7、竖腹杆1-6,N1-6= -12.659 KN,Рlox= 180 cm, loy= 180 cm。Р选用2L 50 x 5 角钢,A = 2 * 4.8 = 9.6cm2, ix=1.53cm, iy=2.30cmР长细比:λx = loxix = 1801.53 = 117.6 < [λ] = 150 Р λy = loyiy = 1802.30 = 78.3 < [λ] = 150Р λz = ξ bt = 3.9 x 505 = 39Рλy>λz,λyz = λy[1+0.16 (λzλy)2] =78.3*[1+0.16 (3978.3)2] =81.4Р查表得φx = 0.450 φyz = 0.646