18m跨梯形钢屋架课程设计

·1钢结构课程设计南昌大学建筑工程学院姓名_________杜巍________________班级_________土木093___________学号______6002109077______指导老师：汤海林·2目录一、设计资料·····················3二、屋架形式、尺寸的确定···············3三、支撑布置·····················4四、荷载计算·····················5五、内力计算·····················6六、杆件设计·····················81.上弦杆·····················82.下弦杆·····················103.端斜杆aB···················114.腹杆······················125.竖腹杆·····················136.屋架杆件截面选择表·····················15七、节点设计·····················161.支座节点“a”·················162.下弦跨中节点“d”···············193.屋脊节点“F”·················204.下弦节点“b”·················235.上弦节点“B”·················25·3单层工业厂房屋盖结构——梯形钢屋架设计一、设计资料某批车间总长60米，跨度A为18米，柱距为6米，屋面材料为预应力大型屋面板（1.5×6米，屋面板需保证与上弦3个点焊牢，故上弦平面外计算长度为3米），屋架形式为梯形钢屋架，并支承于钢筋混凝土柱上，混凝土标号为C25.钢材为Q235·BF,焊条E43型。二、屋架形式、尺寸的确定根据业主需要及屋面排水要求，选用梯形钢屋架,屋架坡度为1/10。屋面材料为预应力大型屋面板，采用无檩屋盖体系。屋架水平布置图如下：屋架计算跨度：。mmll1770015021800015020屋架端部高度取：mmH12140。跨中高：mmilH210020991.02/1770012142H00。屋架高跨比：5971770021000lH。屋架跨中起拱,36500/mmlf取40mm。为了使屋架节点受荷,配合屋面板1.5m宽，腹杆体系大部分采用下弦节间水平尺寸为3.0m的人字形式，上弦节间水平尺寸为1.5m，屋架几何尺寸如图所示。·4全跨半跨三、支撑布置根据车间长度、屋架跨度、荷载情况、屋架上弦设置横向水平支撑剂垂直支撑和系杆，使屋盖成为空间刚度很大的稳定体系，如图。其中：上弦屋脊节点·5处及屋架支座出的系杆为刚性系杆，安装螺栓采用C级，螺杆直径：d=20mm，螺孔直径：d0=21.5mm。四、荷载计算荷载(一)屋面恒载(标准值):屋面板自重2.6kN/m2坡向分布屋架及支撑自重0.25kN/m2水平投影分布(二)屋面可变荷载(标准值)·6坡屋面的屋面可变荷载（雪荷载）0.45KN/m2,水平投影分布。风荷载为吸力，不考虑。各屋架满跨与半跨内力系数见内力系如下图。屋面与水平的夹角a=5.71°，cosa=0.995屋面板自重2.6/cos5.71=2.61kN/m2水平投影分布荷载计算表荷载名称标准值（kN/2m）设计值（kN/2m）预应力屋面板2.612.61×1.35＝3.5235屋架和支撑自重0.250.25×1.35＝0.3375永久荷载总和2.863.861屋面可变荷载0.450.45×1.4＝0.63可变荷载总和0.450.63荷载组合设计屋架时，应考虑以下三种荷载组合：1、全跨永久荷载+全跨可变荷载全跨节点永久荷载及可变荷载：KNF419.4065.163.0861.32、全跨屋架和支撑自重+半跨屋面板自重+半跨屋面活荷载:全跨节点屋架和支撑自重：kNF0375.365.13375.01半跨节点屋面板自重：kNF97.3165.15235.32五、屋架设计要求1、内力计算本设计采用数值法计算杆件在单位节点力作用下各杆件的内力系数（单位节点力分别作用于全跨、半跨），内力计算结果如下表所示。屋架杆件内力组合表杆件名称内力系数（F=1）内力组合值计算杆内力(kN)全跨①半跨②第一种组合F×①第二种组合F3×①+F4×②·7上弦AB0.000.000.000.000.00JK0.000.000.000.000.00BC-9.51-6.69-384.48-242.64-384.48IJ-9.51-2.83-384.48-119.30-384.48CD-9.51-6.69-384.48-242.64-384.48HI-9.51-2.83-384.48-119.30-384.48DE-12.95-8.11-523.32-298.76-523.32GH-12.95-4.83-523.32-193.87-523.32EF-12.95-8.11-523.28-298.76-523.28FG-12.95-4.83-523.28-193.87-523.28下弦ab5.554.06224.45146.65224.45fg5.551.49224.4564.64224.45bc11.797.89476.47287.92476.47ef11.793.90476.47160.61476.47cd12.476.24504.04237.24504.04de12.476.24504.04237.24504.04腹杆Aa-0.50-0.50-20.21-17.51-20.21Kg-0.500.00-20.21-1.52-20.21aB-7.82-5.71-315.92-206.41-315.92gJ-7.82-2.10-315.92-90.96-315.92Bb5.283.50213.58128.02213.58Jf5.281.78213.5873.03213.58Cb-1.00-1.00-40.34-34.97-40.34If-1.000.00-40.34-3.03-40.34bD-3.45-1.83-139.53-69.06-139.53fH-3.45-1.62-139.53-62.29-139.53Dc1.630.2865.7613.9365.76He1.631.3565.7647.9865.76Ec-1.49-1.50-60.27-52.33-60.27Ge-1.490.00-60.27-4.53-60.27Eh0.000.000.000.000.00·8Gi0.000.000.000.000.00Fh0.502.2420.3373.2773.27Fi0.50-1.7420.33-54.1620.33-54.16hc0.502.2420.3373.2773.27ie0.50-1.7420.33-54.1620.33-54.16Fd0.000.000.000.000.002、杆件设计(1)上弦杆整个上弦采用等截面，按EF、FG杆件的最大设计内力设计。N＝-523.28kN上弦杆计算长度：在屋架平面内：为节间轴线长度mmllox30150，在屋架平面外：屋面板需保证与上弦3个点焊牢，故上弦平面外计算长度mmloy3000腹杆最大内力N＝-315.915kN，查表得，中间节点板厚度选用8mm，支座节点板厚度选用10mm。杆件受到的最大弯矩值：mKNdPPMMx19.184/995.0015.342.406.04/)(6.06.0210选用2L160X14，截面地)8(92.6,92.4,8.181,4683231mmcmicmicmWcmWyxxx（1）平面内稳定性验算相应的塑性发展系数2.1,05.121xx，28.612.49/3015x，查表得801.0xKNEANxEx1.42581028.611.186601006.21.1'325222上弦杆在弯矩作用平面内，节间正弯矩和支座负弯矩都是最大弯矩，所以分别利用最大正弯矩和最大负弯矩进行稳定性的验算。用正弯矩：)'/8.01(11ExxxxmxxNNWMAN·9=)1.4258/28.5238.01(1046805.11019.1885.08660801.01028.523363=2/2154.11096.3444.75mmNf对于这种T形截面压弯杆，还应验算截面的另一侧，即)'/25.11(22ExxxxmxNNWMAN=)1.4258/28.52325.11(108.1812.11019.1885.086601028.523363=22/215/96.2238.8342.60mmNfmmN用负弯矩：)'/8.01(22ExxxxmxxNNWMAN=)1.4258/28.5238.01(108.1812.11019.1885.08660801.01028.523363=2/21519.15475.7844.75mmNf平面内的稳定性可以得到保证。（2）平面外的稳定性验算平面外的计算长度mmly30000，35.432.69/3000y，边厚比9.10/58.043.1114/160/0bltby，则双角钢截面的换算长细比为λyz=3.9b[1+l0y2t2/(18.6b4)]/t=3.9×16[1+3002×1.42/(18.6×164)]/1.4=51.03查表得φy=0.852。关于梁的整体稳定系数，现12035.43y，故在正负弯矩下分别取926.00017.01yb和978.00005.01yb。因为在计算长度范围内弯矩图和曲率出现多次符号改变，tx按规范的条文取为0.85。用正弯矩：223631/215/6.10668.3592.7010468926.01019.1885.08660852.01028.523mmNmmNWMANxbxtxy用负弯矩：223632/215/88.15796.8692.70108.181978.01019.1885.08660852.01028.523mmNmmNWMANxbxtxy平面外的稳定性可以得到保证。（3）强度验算截面上无翼缘一边的强度应该验算·102236322/215/8.14338.8342.60108.1812.11019.1886601028.523mmNmmNWMANxxx强度可以得到保证。（4）刚度验算15003.51,15028.61yzx，刚度可以得到保证。（2）下弦杆整个下弦杆采用同一截面，按最大内力所在的cd、de杆计算。N=504.04kN下弦杆平面内计算长度mmlox3000mmloy6000所需截面积为（因跨中有通长系杆）:23mm3.23442151004.504NAf选用2L110×70×10，因,0xoyll故用不等肢角钢，短肢相并,肢背间距a=8mmA＝34.42cm，cm.91ix，cm38.5iy3509.157193000iloxxx，3505.1118.536000iloyyyaaMP215MP5.1463440504040AN，所以满足要求。下弦截面如图：·11（3）端腹杆端腹杆aB（或gJ）最大设计内力设计。杆件轴力：N=-315.92KN计算长度：mmlloyox1919因为oyoxll，故采用等肢角钢，使yiix。选用2L100×8,肢背间距a=8mm则:A＝31.22cm，m3.08cix，mc41.4iy3.6208.39.191ilxx0x150,满