第2章 结构设计－3

武汉理工大学本科毕业设计 2.7 截面设计2.7.1梁的正截面承载力计算及斜截面承载力计算根据“抗震规范”6.2.1条，截面设计应满足梁在跨中截面正弯矩作用下按T形截面计算，梁在支座正弯矩作用下按T形计算，梁在支座处负弯矩作用下按矩形截面计算；梁翼缘宽度取下列三项中之小值：，故翼缘宽度不受此限取梁的有效高度h0跨中正弯矩：h060060540mm（15层） h060035565mm（6层）支座正弯矩：h040035365mm支座负弯矩：h060070530mm（15层） h060050550mm（6层）梁采用C30混凝土： 纵向钢筋为HRB335级：箍筋为HPB235级：判别T截面的类型：跨中:kNmMmax =575.018 kNm,故属于第一类T型截面；支座:kNmMmax =459.33kNm,故属于第一类T型截面；1、梁正截面平配筋计算框架梁正截面承载力计算 底层梁截面配筋 表2.51 截面支座B1跨中支座D1+M-M正M+M-MM（kN.m）367.56.-459.33575.018555.86-342.88bh(mm)300565300530300540300565300530RE0.750.750.750.750.75REM0（kN.m）275.67344.498431.264416.895.257.16Mf1（kN.m）1894. 4641993.1341894.464截面类型第一类T型矩形第一类T型第一类T型矩形s=REM0/(1fcbh02)0.2020.213s=REM0/(1fcbfh02)0.0260.0450.040s=0.51+(1-2s)1/20.9870.8860.9770.9800.879=1-(1-2s)1/20.0260.2280.0460.0410.242As=REM0/fysho1647.792445.432724.792509.751840.00选筋218+322428420+422428328实配面积16492463277624631847=As/bh00.97%1.55%1.72%1.45%1.165 第三层梁截面配筋 表 2.52 截面支座B1跨中支座D1+M-M+M+M-MM（kN.m）161.70-392.20457.273455.42-240.88bh(mm)300565300530300540300565300530RE0.750.750.750.750.75REM0（kN.m）121.275294.15342.95341.565180.66Mf1（kN.m）1894.4641993.1341894.464截面类型第一类T型矩形第一类T型第一类T型矩形s=REM0/(1fcbh02)0.2440.15s=REM0/(1fcbfh02)0.0120.0360.0325s=0.51+(1-2s)1/20.9940.8580.9820.9830.918=1-(1-2s)1/20.0120.2840.0370.0330.163As=REM0/fysho719.8062156.1772155.782049.981237.719选筋20+216720720818420实配面积716.22198219820361256=As/bh00.423%1.38%1.36%1.20%0.79% 第六层梁截面配筋 表2.53 截面支座B1跨中支座D1+M-M+M+M-MM（kN.m）-202.49319.382210.89bh(mm)300550300565300565RE0.750.750.75REM0（kN.m）151.868239.537158.168Mf1（kN.m）1693.8351693.835截面类型矩形第一类T型第一类T型s=REM0/(1fcbh02)0.117s=REM0/(1fcbfh02)0.02280.020s=0.51+(1-2s)1/20.9380.9880.99As=REM0/fysho981.251430.361942.57选筋418220+416320实配面积10171434942=As/bh00.62%0.85%0.56%判别T型截面类型:kNmMmax =575.018 kNm,故属于第一类T型截面；支座:kNmMmax =459.33kNm,故属于第一类T型截面最小配筋率=0.2%.注：RE梁受弯承载力抗震调整系数为0.75 2、框架梁斜截面承载力计算 根据“混凝土设计规范”知：1) 受剪承载力抗震调整系数：RE0.852) 受剪承载力设计值：3) 梁截面组合的剪力设计值应满足： 仅取底层梁举例进行斜截面承载力计算底层框架梁斜截面承载力计算 表2.54截面支座B右支座D左调整后剪力V（kN）27.2697.946REV（kN）23.1796.754bh0（mm2）3005653005650.25cfcbh0484.77REV484.77REV箍筋直径(mm)肢数（n）n=2 10n=2 10Asv1(mm)78.578.5箍筋间距s200200Vcs=0.7ftbh0+1.25fyvAsvh0/s218.227REV218.227REVsv,min=0.24ft/fyv0.19%0.19%=nAsv1/bs0.26%0.26%箍筋间距S(100)200(100)200注:括号内数值为梁端加密区范围内的箍筋间距2.7.2柱的截面配筋混凝土为C30级， 纵筋为HRB335级，箍筋为HPB235级：1、轴压比验算轴压比验算 柱轴压比验算 表2.55 层次柱号柱底轴力N截面AfcA=N/fcA备注1B2362.27350050035750.660.9满足D2207.97760060051480.430.9满足E2280.28150050035750.630.9满足2.正截面承载力计算底层采用对称配筋(见下表) 表2.56 杆件柱A0A1柱B0B1柱B0B1内力项G+EG-EG+EG-EG+EG-E内力值REM0.8329.390.8356.9760.8930.80.8944.190.8382.030.8470.852REN0.82362.2730.82008.3950.81845.7270.82207.9770.82280.2810.81190.522e0=M/N(mm)139.4228.18504.4427.6167.5395.46ea=max(mm)20ei=e0+e1(mm)159.4242.18524.4447.6187.5395.461=0.5fcA/N0.9461.01.741.01.451.01.01.881.02=1.15-0.01l0/h1.0731.01.0731.01.851.01.851.01.0731.01.0731.0=1+(l0/h)212/(1400ei/h0)1.121.0811.031.041.011.05ei179.090.3h0261.870.3h5400.3h4650.3h189.370.3h435.150.3h大小偏心大大大大大大e=376.59459.37787.5712.5386.87632.65x=N/(1fcb)264224.7172.1205255133AS= AS1325.5251325.5252779.7752779.7751733.2841733.284minbh0.0085002=200026520.0085002=200026520.0086002=28802779.820.0086002=28802779.820.0085002=20001733.320.0085002=20001733.32选用配筋每侧316+318每侧422+420每侧418+222AS1366277617773、柱斜截面承载力计算取底层框架柱进行举例计算 表2.57杆件柱B0B1柱D0D1柱E0E1截面柱顶面柱底面柱顶面柱底面柱顶面柱底面内力值REM328.3379.3374.37791.265120.54400.852REV14.5614.5611911979.90979.909REN145617071323193.8646.169674.629=M/Vh048.4556.025.5610.03.010.03REV0.25cfcbh01191072.5646.1691544.4674.6291072.5REV-