轻型门式刚架厂房主体结构1、设计条件1.1、设计资料某单层工业厂房,采用单跨双坡门式刚架,刚架跨度27m,柱距6m,长度48m。一侧墙上两个开间设3.6m×3.6m门一扇,两纵墙轴线位置上,各开间均设窗3.6m×1.2m。刚架柱柱脚标高设为±0.000m,刚架檐口高度为9.0m,从而刚架柱柱高为h=9.0m。屋面坡度1/10。屋面及墙面板均为彩色压型钢板,考虑经济、制造和安装方便,檩条和墙梁均采用冷弯薄壁卷边C型钢,间距为1.5米,钢材采用Q345钢,焊条采用E50型。1.2、设计参数地面粗糙度:B类地震设防烈度:6度设计使用年限:50年结构重要性系数:γ0=1.0基本风压:ω0=0.50kN/m2屋面活载和雪压:ζ0=0.50kN/m22、布置形式刚架平面布置如图所示,刚架形式及几何尺寸如图所示。3、初选截面钢柱采用等截面H型钢,梁柱初选截面均为H450×200×8×12。截面特性:Ix=28181cm4Iy=1602cm4Wx=1252cm3Wy=160.2cm3ix=18.53cmiy=4.42cmSx=707.07cm3A=8210cm24、荷载计算4.1屋盖永久荷载标准值(对水平投影面)彩色型钢板檩条及支撑刚架斜梁自重合计0.25kNm20.05kNm20.15kNm20.45kNm24.2屋面可变荷载标准值基本风压:ω0=0.5kN/m24.3轻质墙面及柱自重标准值(包括柱、墙骨架等)0.5kNm24.4风荷载标准值基本风压:0=1.05×0.50kNm2=0.53kNm2;根据地面粗糙度列别为B类,查得风荷载高度变化系数:当高度小于10m时,按10m高度处的数值采用,z=1.0。风荷载体型系数s:迎风柱及屋面分别为+0.25和-1.0,背风面柱及屋面分别为-0.55和-0.65。4.5地震作用荆州地区抗震设防烈度为6度,根据《全国民用建筑工程设计技术措施----结构》中第18.8.1条的建议,所以不考虑地震作用。4.6荷载标准值计算A、屋面恒荷载标准值:0.45×6/cosα=2.72kNm活荷载标准值:0.50×6=3.00kNmB、柱荷载柱自重标准值:0.45×6=2.70kNmC、风荷载标准值迎风面:柱上qw1k=0.53×6×(+0.25)=0.80kN/m横梁上qw2k=0.53×6×(-1.0)=-3.18kN/m背风面:柱上qw3k=0.53×6×(-0.55)=-1.75kN/m横梁上qw4k=0.53×6×(-0.65)=-2.07kN/m4.7荷载设计值计算屋面恒载g1=γGgk1=1.2×2.72=3.26kN/m柱身恒载g2=γGgk2=1.2×2.70=3.24kN/m屋面活载q=γQQk=1.4×3.0=4.2kN/m风载迎风面:柱上qw1=γQqw1k=1.4×0.80=1.12kN/m横梁上qw2=γQqw2k=-1.4×3.18=-4.45kN/m背风面:柱上qw3=γQqw3k=-1.4×1.75=-2.45kN/m横梁上qw4=γQqw4k=-1.4×2.07=-2.90kN/m5、内力分析(用结构力学求解器计算求得内力,用AutoCAD绘制)qw3=-1.75kN/mqw1=0.80kN/mq=3.00kN/mg1=2.70kN/mqw2=-3.18kN/mqw4=-2.07kN/m1g2=2.70kN/m119.60kN·m荷载图g2=2.70kN/m243.45kN·m142.45kN·mM图39.23kN1.85kN18.33kN0.60kNQ图59.02kN16.24kN8.25kN38.29kN=1252×10×310-22.22×10×1253×10/821041.26kN22.34kN70.42kN12.20kN12.32kNN图60.93kN22.22kN90.09kN6、构件设计和验算及节点设计和验算6.1、截面验算构件宽厚比的验算翼缘部分:b/tf96/12896/12815235fy12腹板部分:h0/tw426/853.25250235fy206满足要求。6.2、刚架梁的验算6.2.1抗剪验算梁截面最大剪力为Vmax=39.23kNVuhwtwfv=426×8×180N=613440N=613.44kN>Vmax=39.23kN满足要求。6.2.2抗弯验算取梁端截面进行验算,N=-22.22kN,V=-59.02kN,M=-243.45kN·m由于V<0.5VuMeNMeNWe/AeWxfNWx/A333=384879019N·mm=384.88kN·m≥M=-243.45kN·m满足要求。6.2.3平面内的稳定N=-22.22kN,M=-243.45kN·m,梁平面内的稳定性验算:计算长度取横梁长度l0x1350021350227135mmxl0x/ix27135/185.3146.44150b类截面,查附表可知,x0.9861.1xWex1x125210310.986=200.66kN/mm<f=310N/mmyt0s235f12521068.268.2122354.44263450.75N0.969243.4510612521031.925=98.29N/mm<f=310N/mmNEx02EAe02220610382101.1146.442kN707.6kNmx1.0NxAe0NmxMxNEx0222200.98682101.0243.4510622.22707.622满足要求。6.2.4平面外的稳定横梁平面外的稳定性验算:考虑屋面压型钢板与檩条紧密相连,有蒙皮效应,檩条可以作为横梁平面外的支承点,但为安全起见,计算长度按两个檩距或隅撑间距考虑,即l0y3015mm对于等截面构件,γ=0,sw1,yl0yiy3015/44.268.2,b类截面,查附表得,y0.668。by4320A0h02yWx0w4.4h042y=4320821042623142=1.925>0.6取y1.070.283/by1.07-0.283/1.925=0.923t1.0NNEx0NExo2=1.0-22.22/707.6+0.75×(22.22/707.6)2=0.969NyAe0tMWe1by222200.668821022满足要求。6.2.5按《钢结构设计规范》(GB50017-2003)校核横梁腹板容许高厚比。梁端截面:281811021818108maxNAEoMyIx222208210243.4510621328181104=2.71184.01186.72181.30N/mm20maxminmax1.97故h0tw53.254800.5x26.2235fy84.60,满足要求。梁跨中截面:maxNAEoMyIx12320142.45106213821028181104=1.50107.67109.17106.17N/mm20maxminmax1.97故h0tw53.254800.5x26.2235fy84.60,满足要求。6.2.6檩条集中荷载下的局部受压承载力。檩条传给横梁上翼缘的集中荷载F=(1.2×0.27×6+1.4×3.0)×1.5kN=9.21kNlz=a+5hy+2hR=(70+5×12+0)mm=130mmcFtwlz1.09.2110381308.86N/mm2f310N/mm2满足要求。验算腹板上边缘的折算应力取梁端截面处的应力N=-22.22kN,V=-59.02kN,M=-243.45kN·mMy1In243.351062134N/mm2183.9N/mm2VSItw59.02103200124194N/mm234.00N/mm22c2c32183.928.862183.98.86334.002=197.47N/mm<1.2f=372N/mm=1252×10×310-60.93×10×1252.48×10/82101.1x22满足要求。6.3刚架柱的验算6.3.1抗剪验算柱截面最大剪力为Vmax=38.29kN,考虑仅有支座加劲肋sh0/tw415.34235fy53.25415.34235/3450.6810.8Vuhwtwfv4268180N613440N613.44kNVmax38.29kN满足要求。6.3.2抗弯验算取梁端截面进行验算,N=-60.93kN,V=16.24kN,M=-243.45kN·m由于V<0.5Vu,故MeNMeNWe/AeWxfNWx/A333=378828361N·mm=378.83kN·m≥M=-243.45kN·m满足要求。6.3.3刚架柱平面内整体稳定性验算。构件最大内力:N=-90.09kN,M=-243.45kN·m刚架柱高H=9000mm,梁长L=27135mm,柱的线刚度为:k2Ic1/h28181104/9000mm331312mm3梁的线刚度为:k1Ib0/2s28181104/27135mm310385mm3k1/k210385/313120.332查表得柱的计算长度系数μ=2.934.刚架柱的计算长度l0xh2.9349000mm26406mmxl0x/ix26406/185.3142.5150b类截面,查附表得,x0.333NEx02EAe02220610382101.1142.52N747.3kNmx1.0Wex1x125210310.333=235.83kN/mm<f=310N/mmyt0s235f12521068.268.2122354.44263450.75N0.890243.4510612521031.925=106.35/mm<f=310N/mmNxAe0900900.33382101.0243.4510690.09747.3226.3.3刚架柱平面外整体稳定性验算。考虑屋面压型钢板与檩条紧密相连,有蒙皮效应,与柱连接的墙梁可以作为横梁平面外的支承点,但为安全起见,计算长度按两个墙梁距离或隅撑间距考虑,即l0y3015mm对于等截面构件,γ=0,sw1,yl0yiy3015/44.268.2,b类截面,查附表得,y0.668。by4320A0h02yWx0w4.4h042y=432082104262314