土木工程學院鋼結構課程設計

1、一、設計題目許昌學院理工樓結構大廳鋼屋架設計二、設計根本資料：1.工程概況圖1柱網(wǎng)布置圖圖1為許昌學院理工綜合樓結構大廳柱網(wǎng)布置圖,跨度為19.8m,長度為51.45m,結構大廳縱向兩排柱子為牛腿柱,設置吊車梁,故需考慮振動荷載.采 用1.8m><7.2m預應力混凝土大型屋面板,15cm厚泡沫混凝土保溫層和卷材屋面. 雪荷載及積灰荷載根據(jù)規(guī)定采用,雪荷載0.7 KN/mm2,屋面積灰荷載 0.07KN/mm2.屋架支撐丁鋼筋混凝土柱上,按皎接點計算.鋼材選用 Q235-B, 焊條選用E43,手工焊.屋架形式及幾何尺寸如下列圖梯形鋼屋架支撐布置如下列圖:'I I3 .何載計算

2、屋面活荷載0.7KN/m 2進行計算.荷載計算表荷載名稱標準值KN/m2設計值KN/m2預應力混凝土大型屋面板自重1.41.4X 1.35 = 1.89屋架及支撐自重0.450.15X 1.35 = 0.608屋面防水層0.40.4 X 1.35 = 0.54找平層0.40.4 X 1.35 = 0.54永久荷載總和2.653.578屋面檢修荷載0.50.5X 1.4= 0.7可變何載總和0.50.7荷載組合方法：1、全跨永久荷載F1+全跨可變荷載F22、全跨永久荷載Fi +半跨可變荷載F23、 全跨屋架包括支撐自重F3+半跨屋面板自重 F4+半跨屋面活荷載 F24、內力計算計算簡圖如下a)b

3、)2 F/2FF7(c)屋架構件內力組合表桿件桿件單位荷F= 1載靜載作用KN/m2活載(KN/m2) 0.7桿件內力計算 內力名編在在全全部屋架大型屋面板1.89在在全組合組合組合稱號左右跨恒載3.578支撐0.608在左在右全部左右部一二三上AB0.000.000.000.000.000.000.000.000.000.000.000.000.000.000.00弦BC-4.69-2.16-6.23-22.28-3.79-8.86-4.09-11.77-3.28-1.51-4.36-143.84-138.02-86.01-143.84桿CD-4.68-2.16-6.22-22.25-3.7

4、8-8.85-4.08-11.75-3.28-1.51-4.35-143.63-137.83-85.89-143.63DE-6.21-3.93-9.00-32.19-5.47-11.73-7.42-17.01-4.34-2.75-6.30-207.85-197.30-116.34-207.85EF-6.20-3.92-8.99-32.17-5.47-11.72-7.42-16.99-4.34-2.75-6.29-207.70-197.15-116.26-207.70FG-5.32-5.32-9.10-32.57-5.54-10.06-10.06-17.21-3.73-3.73-6.37-210

5、.32-196.02-104.32-210.32下ab-1.21-2.82-3.49-12.49-2.12-2.29-5.34-6.60-0.85-1.98-2.44-80.62-72.00-28.38-80.62弦bc1.87-0.831.013.600.613.53-1.571.901.31-0.580.7023.2526.5129.4429.44桿cd2.070.722.318.261.403.911.364.361.450.511.6253.3352.4336.5253.33斜aB-5.06-2.05-6.51-23.31-3.96-9.56-3.87-12.31-3.54-1.43-

6、4.56-150.49-144.99-92.14-150.49腹Bb3.381.834.6816.762.856.393.468.852.371.283.28108.19103.2862.69108.19桿bD-2.15-1.79-3.42-12.25-2.08-4.06-3.39-6.47-1.51-1.25-2.40-79.09-74.28-41.31-79.09Dc0.731.551.836.551.111.382.933.460.511.081.2842.2738.1116.2142.27Cf0.38-1.54-0.71-2.54-0.430.72-2.90-1.340.27-1.07

7、-0.50-16.41-12.292.99-16.41Fd-1.451.36-0.48-1.73-0.29-2.732.56-0.91-1.010.95-0.34-11.16-14.81-21.82-21.82豎Aa-0.500.00-0.50-1.79-0.30-0.950.00-0.95-0.350.00-0.35-11.55-11.55-8.63-11.55桿Cb-0.930.03-0.91-3.27-0.56-1.770.06-1.73-0.650.02-0.64-21.10-21.18-16.07-21.18Ec-0.950.03-0.93-3.34-0.57-1.800.05-1.

8、77-0.670.02-0.65-21.58-21.66-16.42-21.66Gd0.080.080.853.030.520.150.151.600.060.060.5919.5816.683.9019.585. 桿件設計1、上弦桿整個上弦采用等截面,按FG桿件的最大設計內力設計,即 N= 210.32KN上弦桿計算長度：在屋架平面內：lox lo 1.508m , loy 2 X1.508 3.016m上弦截面選用兩個不等肢角鋼,短肢相并.腹桿最大內力N= - 115.16 KN ,中間節(jié)點板厚度選用6mm,支座節(jié)點板厚度選用. N210.32X10328mm 設入=60,力=0.807,

9、截面積為 A1327.4mm4 f0.807X215lx需要回轉半徑：iyl°x 1.508=m = 25.1mm603.016_m=50.3mm60入l0y查表選用2q廠110X 70X 6yx6xrxI .y 110X 70X6上弦截面驗算. l ox 1508Xx =m = 75.0mmIx20.1.l0y 3016入 y =m = 85.2mmIy 35.4滿足長細比要求,入y入x查表4 y= 0.655210.32 X103NA 0.655X2120= 151.5MPa<215MPa滿足要求屋架桿件截面選擇表0桿 件 編 號內力(KN)計算長度cm截面規(guī)格截面面積(c

10、m2)回轉半徑(cm長細比容許長細比入穩(wěn)定系數(shù)計算應力N4 yA(N/mnS)l 0xl0yixiy入x入y巾X巾y上弦FG-210.32150.830.162" 110X 70 X 621.22.013.5475.085.2150.000.7200.655151.55下弦ab-80.623008852廠 100X 80 X 1034.402.534.63118.58191.14150.000.4470.204-114.88斜腹aB-150.492532532" 100X 63 X 1031.001.744.86145.4052.06150.000.3220.847-150

11、.76Bb108.19209.04261.32 " 90 X 56 X 514.421.594.32131.4760.49350.000.3830.807195.89bD-79.09229.12286.42廠 90 X 56 X 514.421.594.32144.1066.30150.000.3290.774-166.71Dc42.27229.12286.42廠 70 X 45 X 511.221.283.14179.0091.21350.000.2270.614165.96Cf-16.41249.92312.42" 100 X 63 X 619.241.794.7813

12、9.6265.36150.000.3490.780-24.44Fd-21.82249.92312.42" 100 X 63 X 619.241.794.78139.6265.36150.000.3490.780-32.50豎桿Aa-11.55159.21992 " 63 X 40 X 58.121.143.09139.6564.40150.000.3490.786-40.76Cb-21.18183.22292廠 70X 45 X 511.221.283.41143.1367.16150.000.3330.769-56.69Ec-21.66207.22592廠 75 X 50

13、 X 1023.601.383.72150.1469.62150.000.3080.757-29.80Gd19.58231.22892廠 70 X 45 X 511.221.283.14180.6392.04350.000.2250.60877.56抗剪強度設計值f：1、節(jié)點設計 下弦節(jié)點 用E43型焊條角焊縫的抗拉和抗壓、160MPa.N=29.44KN041 63Knr90X 56X5a.下弦節(jié)點“ b,設“ Bb桿的肢背和肢尖焊縫為hf = 6mm.所需的焊縫長度為肢背：lw0.75N2f0.75X081902>0.7>6 X60=60.37mm,取 70mm.肢尖：l w0

14、.25N2heffw0.25X081902為.7><6 X6020.12mm,取 50mm.設“bD桿的肢背和肢尖焊縫為 hf = 6mm.所需的焊縫長度為肢背:0.75N2heffw0.75 X90902>0.7>6 花0=44.13mm,取 50mm.肢尖:''l w0.25Nw2heff0.25*90902>0.7><6 X6014.71mm,取 50mm."Cb桿內力很小,取 hf = 6mm.綜合取節(jié)點板尺寸 300mm x 230mm下弦與節(jié)點板連接的焊縫長度為30.0cm , hf= 6mm.焊縫所受的力為左右兩

15、下弦桿的內力差 N = 110.06KN ,受力較大處的肢背出的焊縫應力為34.1MPa <160MPa0.75X10060Tf 2 >0.7>300 12焊縫強度滿足要求1.上弦節(jié)點“ B"Bb桿與節(jié)點板的焊縫尺寸同上.175 14511.*N=0KNN=143.84KN2 r 110X 70X666 57°2100X 63X 10*290X 56X5N=150. 49KNN=108. 19KN上弦節(jié)點"B"設"aB桿的肢背和肢尖焊縫 hf = 8mm和6mm,所需焊縫長度為肢背：l w0.75N2heffw0.75X504

16、90、/ 、/ = 62.98mm,取 70mm 2>0.7><8 X60肢關：l w0.25Nw2heff0.25X50490-、/ 、/ = 27.99mm,取 50mm 2>0.7>6 X60節(jié)點板上邊緣縮進上弦肢背8mm.用槽焊縫把上弦角鋼和節(jié)點板連接起來.槽焊縫作為兩條焊縫計算,需在強度設計值乘以 0.8的折減系數(shù).假定集中荷載P與上 弦垂直,上弦肢背槽焊縫內的應力計算如下：hf =6mm , hf = 8mm上弦與節(jié)點板焊縫長度為 290mm,那么2 P223101 2g 宮(q = J(075X43840)(q2>0.7hflw2>0.7

17、>6 濃90 12)=53.49MPa <0.8f1w = 128MPa上弦肢尖角焊縫的切應力為2 Pk2(N1 疆)2 -) 2X.222>0.7hfl'w(0.25X43840)2 (冬.1 )2 2X.222 >0.7 >6 >(290 12)= 53.49MPaV0.8ffw = 128MPa2.上弦節(jié)點“ C設"Cb桿的肢背和肢尖焊縫為 hf = 6mm.所需的焊縫長度為肢背：l w0.75N . - w2heff0.75>21180口、/ 、/= 11.8mm,取 50mm.2>0.7 >6 滯0肢尖：l w0

18、.25N . - w2heff0.25 >21180-7、 / 、 ,= 3.9mm,取 50mm.2 >0.7 >6X60驗算節(jié)點板強度上弦與節(jié)點板焊縫長度為173mm,那么2/ P2/ 23101.2k1(N1 疆)()(0.75 *)()2X.222X.222>0.7hfl'w2>0.7>6>(173 12)= 7.00MPaV0.8ffw= 128MPa上弦肢尖角焊縫的長度為126mm的切應力為(0.25X43840)2 (己.1 )22X.222 P k2(N1 N2)()、 =2>0.7hflw2>0.7>6 為2

19、6 12)=9.8MPa V0.8ffw= 128MPa4.屋脊節(jié)點“ K設拼接角鋼與受壓弦桿之間的角焊縫hf = 8mm,那么所需焊縫計算長度為一條焊上150150,1212_ 一 一 - ,- N=210. 32KN6|VIIII0312廠110X 70X6IIPI如 r70X45X5屋脊節(jié)點"G"58.68mm拼接角鋼長度ls 2(lw 2hf)+弦桿桿端空隙20,拼接角鋼長度取180mm.上弦與節(jié)點板之間的槽焊縫,假定承受節(jié)點荷載,驗算如下設"FG桿的肢背和肢尖焊縫為 hf = 8mm和6mm.所需的焊縫長度為肢背：l w0.75Nw2heff0.75切1

20、03202>0.7>8 X60=88.02mm,取 110mm.肢尖：l w0.25N2f0.25X103202>0.7><6 X6039.12mm,取 60mm.驗算節(jié)點板強度上弦與節(jié)點板焊縫長度為150mm,那么Jk1N2 -)J(0.75 >210320)2 (01)2V2X.22 2X.222>0.7hflw2為.7>8*50 12)= 102.24MPa <0.8f：=128MPa上弦肢尖與節(jié)點板的連接焊縫,應按上弦內力的15%計算,lw = 117- 6 15 =96mm,焊縫應力為一 NTf0.15X102302X.7X 為6

21、39.15MPa6>O.15X10230>54.32X.7X )962132.71MPaM bf(39.15)2 (132.71)21.22115.61MPa<160MPa3.支座節(jié)點“ A為了便于施焊,下弦桿角鋼水平肢的底面與支座底板的凈距離取160mm.在節(jié)點中央線上設置加勁肋,加勁肋的高度與節(jié)點板高度相等,厚度 10mm.N=11.55KN120 一 120(1)支座底板的計算.支座反力R= 23101 X 6 (豎向支座反力單位系數(shù))=138606N.設支座地板的平面尺寸采用240x 360mm,現(xiàn)僅考慮有加勁肋局部的底板承受支座反力,那么承壓面積為 280 X 230= 64400mm2.驗算柱頂混凝土強度