防護(hù)棚搭拆施工方案

防護(hù)棚搭拆施工方案#滿足要求！軸心受壓構(gòu)件的穩(wěn)定系數(shù)計(jì)算：斜撐計(jì)算長(zhǎng)度lo=kji2h=1.155*1.3OO*1.789=2.686m長(zhǎng)細(xì)比入=l0/i=2686/15.9=168.93查《規(guī)范》JGJ130-2011表A.0.6得，(p=0.251o=N/((pA)=8084.412/(0.251x450)=71.575N/mm2o<[f|=205N/min2滿足要求！第2層防護(hù)層傳遞給斜撐荷載計(jì)算(1)橫向斜撐驗(yàn)算承載力使用極限狀態(tài)格構(gòu)柱：F=1.2(gkla+0.035)(la+a1)/2=1.2x(0.5x0.4+0.035)x(2.6+0.4)/2=0.424kN橫向斜撐計(jì)算簡(jiǎn)圖如下：0.424k0.424k0.424k0.424k0.424k0.424k0.424ka.424k0.424k0.424k0.424kQ.424k0.424k0.424k0.424k.0.424kNT山山4T山I14T l1山41Tv400 1000 3200 1000 400橫向斜撐最大支座反力：R2max=3.195kN橫向斜撐軸向力：N22=R2max/cosa1=3.195/cos63.435°=7.144kNN=N21+N22=15.229kN斜撐自由長(zhǎng)度：h=(H-(n-1)h1-h2)/cosa1=(6.3-(2-1)x0.8-4.8)/cos63.435°=1.565m斜撐計(jì)算長(zhǎng)度10=k卩2h=1x1?3x1?565=2?035m長(zhǎng)細(xì)比入=l0/i=2034.822/15.9=127.976<250滿足要求！軸心受壓構(gòu)件的穩(wěn)定系數(shù)計(jì)算：斜撐計(jì)算長(zhǎng)度lo=kp2h=l?155*l?3OO*l?565=2?35Om長(zhǎng)細(xì)比入=l0/i=2350/15.9=147.81查《規(guī)范》JGJ130-2011表A.0.6得，9=0.32o=N/(9A)=15228?61/(0?32x450)=105?754N/mm2o<[f]=205N/mra2滿足要求！七、立桿穩(wěn)定性驗(yàn)算立桿布置格構(gòu)柱鋼管截面慣性矩I(mm4)113600立桿計(jì)算長(zhǎng)度系數(shù)卩11.3鋼管截面抵抗矩W(mm3)4730立桿截面回轉(zhuǎn)半徑i(mm)15.9鋼管抗彎強(qiáng)度設(shè)計(jì)值[f](N/mm2)205立桿截面面積A(mm2)450立桿荷載計(jì)算1、防護(hù)棚結(jié)構(gòu)自重NG1k鋼管長(zhǎng)度：L=n[(la+ a1) ((lb+2a1)/a+1)/2+ lb]+2( l12+(H-h2)2)0.5+4H=2x[(2?6+0?4)x((5?2+2x0?4)/0?4+1)/2+5?2]+2x(32+(6?3-4?8)2)0.5+4x6?3=90?308扣件數(shù)量:m=2n[((lb+2a1)/a-3)/2+1x4]=2x2x[((5.2+2x0.4)/0.4-3)/2+1x4]=40個(gè)NG1k=0?035L+0?015m=0?035x90?308+0?015x40=3?797kN2、防護(hù)棚構(gòu)配件自重NG2k防護(hù)層防護(hù)材料自重標(biāo)準(zhǔn)值NG2k1=nxgk1x(la+ a1)x(lb+2a1)/2=2x0.5x(2.6+0.4)x(5.2+2x0.4)/2=9kN欄桿與擋腳板自重標(biāo)準(zhǔn)值NG2k2=gk2x(la+a1)=0.11x(2.6+0.4)=0.33kN縱向外側(cè)防護(hù)自重標(biāo)準(zhǔn)值NG2k3=gk3x(la+a1)=0.2x(2.6+0.4)=0.6kNNG2k=NG2k1+NG2k2+噸2義3=9+0?33+0?6=9?93kN經(jīng)計(jì)算得到，靜荷載標(biāo)準(zhǔn)值：NGk=NG1k+NG2k=3.797+9.93=13.727kN3、沖擊荷載標(biāo)準(zhǔn)值NQkNQk=Pk=lkN立桿荷載設(shè)計(jì)值：N=l.2NGk+l?4NQk=l.2X13.727+1.4xl=17.872kN立桿的穩(wěn)定性驗(yàn)算1、 立桿長(zhǎng)細(xì)比驗(yàn)算立桿自由長(zhǎng)度h取立桿步距1.8m立桿計(jì)算長(zhǎng)度l0=kjiih=lxl.3xl.8=2.34m長(zhǎng)細(xì)比A=lo/i=234O/l5.9=147.17<210滿足要求！軸心受壓構(gòu)件的穩(wěn)定系數(shù)計(jì)算：立桿計(jì)算長(zhǎng)度lo=kji2h=l.155*1.300*1.800=2.703m長(zhǎng)細(xì)比A=lo/i=2703/15.9=169.98査《規(guī)范》JGJ130?2011表A.0.6得,(p=0.2482、 立桿穩(wěn)定性驗(yàn)算o=N/4/((pA)=17872.293/4/(0.248x450)=40.036N/mm2G<[f]=205N/mm2滿足要求！八、立桿地基承載力驗(yàn)算地基土類型粘性土地基承載力特征值fg(kPa)140地基承載力調(diào)整系數(shù)kc1墊板底面積Nn