钢结构课程设计报告

WordWord资料设计资料：北京地区某金工车间。采用无檩屋盖体系，梯形钢屋架。厂房长度为72m，跨度为27m,柱距6m,厂房高度为15.7m。车间内设有两台200/50kN中级工作制吊车，计算温度高于-20℃。采用三毡四油，上铺小石子防水屋面，水泥砂浆找平层，厚泡沫混凝土保温层，1.5m*6m预应力混凝土大型屋面板。屋面积灰荷载0.3kN/m2,屋面活荷载0.3kN/m2,雪荷载为0.4kN/m2,风荷载为0.45kN/m2。屋架铰支在钢筋混凝土柱上，上柱截面为400mm*400mm，混凝土标号为C20。要求设计钢屋架并绘制施工图。钢材及焊条钢材选用结构的重要性对于重型工业建筑结构、大跨度结构、高层或超高层民用建筑结构和重级工作制吊车梁等都是重要的一级结构。荷载的性质结构构件承受的为静力荷载连接方法为焊接类型,结构不可避免地会产生残余应力、残余变形及各种焊接缺陷,有导致结构产生裂纹或脆性断裂的危险。工作环境计算温度高于-20℃。综上：结构构件承受的为静力荷载在＞-20℃,焊接结构，选择Q235B焊条选用对Q235B型钢焊件用E43系列型焊条。钢屋架的外形和几何尺寸屋架外形选用梯形屋架、平行弦几何尺寸（1）屋架计算跨度i=i-2义150=27000-2*150=26700mm0（2）屋架的高跨比H/l应在经济范围内，选择尸1/10。（3）腹杆体系采用节间为3m的人字形式（4）屋架跨中起拱取£刈/50027m轴线处两端高度h’取1990mm厕屋架26.7m处，两端高度取h=h0 0 0i02012.36m。屋架跨中起拱高度f按1/500考虑，取53.4mm。屋架的支撑布置图表1屋架单跨尺寸图表2XG3XG3XG3XG3XG2XG3XG9XG3XG3XG3CC1XG2XG2XG2XG2CC4XG2XG2XG2XG2XG2CC12-2600060006000600060006000600060006000600060006000图表1屋架单跨尺寸图表2XG3XG3XG3XG3XG2XG3XG9XG3XG3XG3CC1XG2XG2XG2XG2CC4XG2XG2XG2XG2XG2CC12-2600060006000600060006000600060006000600060006000450045DO45DO450045004500图表3屋架上弦支撑构件图表4屋架下弦支撑构件荷载计算屋面荷载与雪荷载不会同时出现，计算时，取较大的雪荷载与积灰荷载同时考虑。则活荷载0.4kN/m2进行计算。屋架沿水平投影面积分布的自重(包括支撑)按经验公式g=(0.12+0.0111)kN/m2计算，跨度单位为米(m)。k荷载计算表标准值设计值*N/m")(kN/mA2)荷载名称原值*1.2*1.35*1.4*1.4*0.7预应力混凝土大型屋面板1.41.681.89三毡四油防水层0.40.480.54找平层0.40.480.54泡沫混凝土保温层0.10.120.135找平层0.50.60.675屋架和支撑自重0.41370.496440.558495永久荷载总和3.21373.856444.338495屋面活荷载0.40.560.392积灰荷载(永久控制时乘1.00.30.420.42可变荷载总和0.70.980.812因为，3.85444+0.98<4.338495+0.812,所以永久荷载起到控制作用，设计屋架时，应考虑以下三种荷载组合。1、全跨永久荷载+全跨可变荷载F=(4.338+0.812)x1.5x6=46.35446kN则全跨永久荷载+半跨可变荷载全跨节点永久荷载：F=4.338x1.5x6=39.04646kN1半跨节点可变荷载：F=0.812x1.5x6=7.308kN

2全跨屋架(包括支撑)自重+半跨屋面板自重+半跨屋面活荷载全跨节点屋架自重：F=0.558x1.5x6=5.026455kN3半跨节点屋面板自重及活荷载F=(1.89+0.392)x1.5x6=20.538kN

4内力计算

图表6全跨内力图图表8右跨内力图图表7左跨内力图根据sap84计算屋架构件内力组合表如下:杆件名称内力系数第一种组合F*(1)第二种组合第三种组合计算杆件内力(kN)全跨⑴左半跨⑵右半跨⑶F1*(1)+F2*(2)F1*(1)+F2*(3)F3*(1)+F4*(2)F3*(1)+F4*(3)最大拉力最大压力上弦AB0.000.000.000.000.000.000.000.000.000.00BC/CD-9.98-7.50-3.10-462.62-444.49-412.34-204.20-65.75-444.49DE/EF/FG-16.39-11.90-5.63-759.75-726.94-681.12-326.79-198.01-726.94GH/HI/IJ-19.17-12.40-8.48-888.61-839.14-810.49-351.03-270.52-839.14下弦ab5.364.121.56248.55239.48220.79111.5759.0559.05bc13.319.784.42616.98591.21551.99267.85157.62616.98157.62cd18.2412.197.59845.51801.29767.65342.04247.50845.51

de17.819.909.90825.57767.79767.79292.91292.91825.57-10.-7.7-2.-466-414.6-449.aB07394.79-449.698-209.38-111.00697.95.82.6367.328.9367Bb32459352.173159.3994.08.59-6.4-4.4-2.-300-253.0-285.bD8455.38-285.472-123.76-84.94474.62.82.2213.196.0213斜Dc01523200.15680.8369.33.23-3.5-1.3-2.-162-157.3-157.腹杆cf1077.70-146.520-44.24-74.5330fG-2.7-0.4-2.-125-109.01-125.6-23.64-70.46-125.0977.167670.70.71.833.399.Gd244857.0199.9618.8241.41961.12.9-2.53.766.-39.3dg6120766.5629.2265.60-39.355651.93.6-2.88.0216-35.6gJ05207216.71-11.7184.51-35.63.713

fE0.730.730.0033.8433.8428.5018.663.6733.84fF-1.00-1.000.00-46.35-46.35-39.05-25.56-5.03-46.35gH0.670.670.0031.0631.0626.1617.133.3731.06gI-1.00-1.000.00-46.35-39.05-39.05-25.56-5.03-39.05竖杆Aa-0.50-0.500.00-23.18-23.18-19.52-12.78-2.51-23.18bC-1.00-1.000.00-46.35-46.35-39.05-25.56-5.03-46.35cE-1.50-1.500.00-69.53-58.57-58.57-38.35-7.54-58.57dH-1.50-1.500.00-69.53-58.57-58.57-38.35-7.54-58.57eJ0.010.080.080.460.980.981.691.691.69六、杆件设计1、上弦杆GH/HI/IJ整个上弦杆采用等截面，按GH/HI/IJ杆件的最大设计内力设计，即N=-888.61kN上弦杆长度：在屋架平面内，为节间轴线长度，即l=l=150.8cm0x0在屋架平面外：本屋架为无檩体系，并且认为大型屋面板只起刚性系杆作用，根据支持布置和内力变化情况，取/为支撑点间的距离，即0yl=3xl=452.4cm

0y 0x根据腹杆的最大内力n=-463.54kN，查表2.8得屋架节点板厚度为aBt=12mm。屋架支座厚度t=14mm。假定X=60，P=0.807A=JL …①.f= 888610=4723.5mm2(0.875x215)l、一石=2.513cml7唬=7.54cm选用2L160x100x12短肢相并，A=60.2cm2,i=2.82cm,i=8.76cmxy验算，九=L '=-°xxi=150.8/2.82=53.48＜鼠］=150,yi=452.4/8.76=34.43＜鼠］=15xy0。①=0.808,xo=N/①A=88610/(0.808*6020)=182.69n/m2<f=215n/m2下弦杆de整个下弦杆采用等截面，按下弦杆的最大应力Ned=-845.51kN计算。/ 285cm,7=300000-2x150=29700/2=14850mml= 7l ，0x 0y 2则所需截面积为A=N=845510/215=3932.60mm2=39.32cm2f选用2L140x90x10短肢相接， A=44.5cm2>39.32cm2,i=2.56cm,i=6.84cmxy九二-0xxi=300/2.56=117<350

xl入=-0Xyi=1485/6.84=217<350y端斜杆aBNaB=-466.79kNl二l=253.5cm,选用2L100x10,A=44.6cm2,i=2.56,i=6.840x0y x y验算：九二-0xxi=253.5/3.08=83.11<150,xl入=0yyi=253.5/4.56=55.11<150y9=0.681x

o=N饵A=466790/(0.662*4460)=182.67N/mm2<219N/mm2。腹斜杆dg-gJ此杆为再分式桁架腹杆，在g节点处不断开，两段内力不同:最大拉力：Ndg=66.56kN NgJ=100.86kN最大压力：Ndg=39.35kN NgJ=35.63kN在桁架平面内l0x=224.9cm。在平面外，则按公式rl在桁架平面内l0x=224.9cm。在平面外，则按公式rl=l0.75+0.250y1计算：l=/0.75+0.250y1NrNjrl=449.80.75+0.250y35.63)39.35,=337.35cm选用2L63X6,A=11.44cm2,i=1.93cm,i=3.06。验算；=工=224.9/1.93=116.53<150

ix入=1=337.35/3.06=110.25<150

yiy9=0.386

yo=N=39350/(0.386*1144)=89.12N/mm2<215N/mm2m9A竖杆dHN=-58.57kN,l

dH l0x=0.8*304=243.2cm,N=-58.57kN,l

dH l0x0y2L63X52L63X5,A=12.28cm2,i=1.94cm，xy验算；九=1=243.2/1.94=125.36<150

xix入=2=400.11/3.04=100<150yiy①=0.413xo=N=58570/(0.413*1228)=115.48N/mm2<215N/mm2m①A竖杆aANA=-23.18kN,因为是支座坚杆，所以l=l=201.24cm,因为内力较小，aA l0xl0y=所以按总选取。贝ki=i=201.24/150=1.34cm,按其查表，2L45x6,xyA=10.16cm2,i=1.36,i=2.36xy其他各杆的截面设计：名称杆件编号内力(kN)计算长度(cm)截面形式和规格2*截面面积cm2回转半径cm长细比容许长细比(八)稳定系数计算应力N/mm2loxloyixiy八x八y上GH/-888150.301.2L160*160.2.8.53.434.41500.8182.弦HI/IJ.61806000*12208276830869下de845.285.14852L140*944.2.6.111.217.3501189.弦5100.000*10605684331158

斜腹杆aB-466.79253.5253.52L100*1038.63.054.683.1155.111500.662182.67Bb367.59208.64260.802L90*621.202.794.1374.7863.153501173.39bD-300.38229.52286.902L100*623.803.104.5174.0463.611500.726173.84Dc213.23228.72285.902L70*513.742.163.31105.8986.373501155.19cG-162.70208.70313.052L90*621.202.794.1374.8075.801500.72106.59Gd41.56260.08325.102L63*512.281.943.04134.06106.94350133.84dJ100.86224.90337.352L63*614.581.933.06116.53110.251500.44560.65-39.35fE33.84150.64188.302L50*59.601.532.5398.4674.43350135.25gH31.06162.16202.702L50*59.601.532.53105.9980.12350132.35

竖杆Aa-23.18201.24201.242L45*610.161.372.36146.8985.271500.32769.76bC-46.35183.20229.002L63*510.161.372.36133.7297.031500.373122.32cE-69.53207.20259.002L63*512.281.943.04106.8085.201500.516109.73dH-69.53243.20304.002L63*512.281.943.04125.36100.001500.413137.10eJ1.69267.20334.002L63*512.281.943.04137.73109.871500.3563.87fF-46.35103.60129.502L45*610.161.372.3675.6254.871500.71763.63gI-46.35121.60152.002L45*610.161.372.3688.7664.411500.63372.08七、节点设计下弦节点b的设计由腹杆内力计算腹杆内力计算腹杆与节点板连接焊缝的尺寸，即h和f/，然后根据/的大小按比例绘出节点板的形状和尺寸，最后验算下弦杆与ww节点板的连接焊缝。用E43型焊条角焊缝的抗拉、抗压和抗剪强度设计值fw=160MPa。f设“Bb”杆的肢背和肢尖焊缝勺=8mm和6mm,则所需的焊缝长度为(按等肢角钢连接的角焊缝内力分配系数计算)肢背：l'=0.7N=0.7*367590/(2*0.7*8*160)=143.59,取150mmw2hfwff肢尖：l〃=0.3N=0.3*367590/(2*0.7*6*160)=82.05,取90mmw2hfwff设“bD”杆的肢背和肢尖焊缝g=8mm和6mm，则所需的焊缝长度为肢背：l'=0.7N=0.7*300380/(2*0.7*8*160)=117.33,取120mmw2hfwff肢尖：n=0.3N=0.3*300380/(2*0.7*6*160)=67.05,取90mm2hfwff

图表9下弦杆节点b“Cb”杆的内力很小，焊缝尺寸可按构造确定，取h=5mm。根据上f面求得的的焊缝长度，并考虑杆件之间应有的间隙及制作和装配等误差，按比例给出节点详图(如图表9)，从而确定节点板尺寸为350mm*445mm。下弦与节点板连接的焊缝长度为44.5cm，h=6mm。焊缝所受的力为左右两下f弦杆的内力差为an=616.98-248.55=368.43kN,受力较大的肢背处的焊缝应力为t=0.75*368430/(2*0.7*6*(445-12))=70.91MPa<160MPaf该焊缝满足强度要求。上弦节点B的设计“Bb”杆与节点板的焊缝尺寸和节点“b”相同。“aB”杆节点板的

焊缝尺寸按上述同样方法计算得N=-466.79kNaB设“。B”杆的肢背和肢尖焊缝h=10mm和6mm,则所需的焊缝长度f为。l'=0.7N=0.7*466790/(2*0.7*10*160)=145.87mm，W150mm-2hfwffl〃=0.3N=0.7*466790/(2*0.7*6*160)=104.19mm，取120mmw2hfwff为了方便在上弦搁置大型屋面板，节点板的上边缘可缩进肢背8mm，用塞焊缝连接，此时，图表10上弦B节点设计图用塞焊缝连接，此时，图表10上弦B节点设计图h2、节点板厚度=t*0.5=12*0.5=6mmWordWord资料WordWord资料l'=1"=1-2hf=460-10=450mm。承受的集中力为P=46.35kNowwT二P= 46350 =12.26N/mm2Vfw=160kN/mm2f2义0.7义h义12x0.7x6x450 ffw肢尖焊缝承担的弦杆内力差，nn=462620-0=462620上帅偏心距e=10-3=7cm,则偏心弯矩为M=Nxe=462620*72=33308457.18N/mm2,设h=8mm,则ANANT= f2x0.7xh1fw—462620—=89.79N/mm2Vfw=160N/mm22x0.7x8x460 fM33308457.18x6-8433o=——= =84.33N/mm2Vfw=160N/mm2fW 2x0.7x8x4602 fwl|0f-1+T21,8433丫+89.792=113.32N/mm2Vfw=160N/mm2\l[BJf敢1.22J %满足要求。上弦跨中拼接点J的设计弦杆的拼接，采用拼接角钢。为了使拼接角钢在拼接处能紧贴被连接的弦杆和便于施焊。需将拼接角钢削棱切肢。设焊缝高度为h=8mm,fA=(t+h+5)=12+8+5=25mm。拼接角钢与弦杆的连接焊缝按被连接弦杆的最大内f力计算，N「-888.61kN,每条焊缝按以下算法：1=N= 888610 =247.94mm,取250mmw4x0.7hfw4x0.7x8x160ff拼接角钢总长度L=2*lw+20=520mm 。A=(t+h+5)=12+8+5=25mm,按上弦坡度热弯。f计算屋脊处弦杆与节点板的连接焊缝，取人=5mm,则需要的焊缝长f度为：2Nsina—P=2义888610义sin6。—46350—3112mml= .攻8x0.7hfw8义0.7义5*160ff按图布置节点板长度。图表11上弦中跨节点设计图下弦跨中拼接点e的设计将拼接角钢削棱切肢。设焊缝高度为h=8mm，fA=(t+h+5)=12+8+5=25mm。拼接角钢与弦杆的连接焊缝按被连接弦杆的最大内f力计算，Ned=-845.51kN，每条焊缝按以下算法：l=N= 845510 =235.91mm，取240mmw4x0.7hfw4x0.7x8x160

ff拼接角钢总长度L=2*lw+50=530mm,A=(t+h+5)=12+8+5=25mm。f弦杆较大内力为Ned=-845.51kN，则根据弦杆与节点连接一侧的焊缝强

度按正式计算肢背焊缝0.15KNIw= 1——max2x度按正式计算肢背焊缝0.15KNIw= 1——max2x0.7hfwff=0.15x0.7x845510=79.27mm2x0.7x5x160取85mm。肢尖焊缝0.15KN,=0.15x0.3x845510=33.97mm,lW= 2max取40mm。2x0.7hfw2x0.7x5x160ff节点板长度：L=85*2+50=220mm,取300。如下图布置:图表12下弦中跨节点设计图支座节点a的设计为了便于施焊，下弦杆角钢水平肢的底面与支座底板的净距离取160mm。在节点中心线上设置加劲肋，加劲肋的高度与节点板的高度相等，厚度14