b=[0.1+(24+1.5)×0.6]×0.3=4.62kN/m1、抗弯验算σ=Mmax/W=max[0.077×5.6×0.32+0.1×0.53×0.32,-0.107×5.6×0.32+0.121×0.53×0.32,-0.071×5.6×0.32-0.107×0.53×0.32]×106/11250=4.28N/mm2≤[f]=15N/mm2满足要求!2、挠度验算νmax=0.632q2l4/(100EI)=0.632×4.62×3004/(100×10000×84375)=0.28mm≤[ν]=l/400=300/400=0.75mm满足要求!3、支座反力计算设计值(承载能力极限状态)Rmax=1.143q1静l+1.223q1活l=1.143×5.6×0.3+1.223×0.53×0.3=2.11kN标准值(正常使用极限状态)R'max=1.143q2l=1.143×4.62×0.3=1.58kN五、小梁验算小梁类型方木小梁材料规格(mm)50×100小梁抗弯强度设计值[f](N/mm2)15.44小梁抗剪强度设计值[τ](N/mm2)1.78小梁弹性模量E(N/mm2)9350小梁截面抵抗矩W(cm3)83.33小梁截面惯性矩I(cm4)416.67计算简图如下:承载能力极限状态q1=0.9×1.2×(G1k2-G1k1)×l=0.9×1.2×(0.3-0.1)×0.3=0.06kN/mq2=Rmax/L=2.11/0.3=7.05kN/mF1=0.9×1.2×0.5×0.3×0.6=0.1kN/mF2=0.9max[1.2×(0.1+(24+1.1)×0.18)+1.4×2,1.35×(0.1+(24+1.1)×0.18)+1.4×0.7×2]×0.3×(2-0.61-0.3/2)/2+0.9×1.2×0.5×0.3×(0.6-0.18)=1.46kN/m
全文预览
