T型梁的截面設(shè)計(jì)

《鋼筋混凝土結(jié)構(gòu)設(shè)計(jì)與計(jì)算實(shí)訓(xùn)》—鋼筋混凝土T形截面梁的配筋設(shè)計(jì)班級(jí)姓名學(xué)號(hào)b'=1200mmff=11.5cdg二0.56bM二1202.5df二280sda二30+0.07x1000二100mmsh二1000一100二900mm0TOC\o"1-5"\h\zh110yM二1202.5(fb'h'(h—f二11.5x1200x110(900-)二1283KN.m0dcdff022屬于第一類T型梁x由yM=fb'x(h——)得:0dcdf021202-5x106=11-5x1200x(900一i)x2—1800x+174275x=1697.5mm(舍)1受拉鋼筋面積：Ax=102.5mm<h'=110mm2ffb'x11.5x1200x102.5cdf==5052mm2280現(xiàn)選用4?32+4?25sdA=3217+1964=5181mm2混凝土保護(hù)層厚度取c=35mmS=250—2x35—2x35.8=108.4mm>40>1.25d,滿足構(gòu)造要求。3217x(35+35.8)+1964x(35+2x35.8+28.4)“=95mm則實(shí)際有效咼度h051813217+1964=1000—95=905mmA

p=s

bh0

截面復(fù)核250x905=2.3%>p=0.2%minfb'h'=11.5x1200x110=1.52KNfA=280x5181=1.45KNX=sd_fcdbfsd280x5181“,…105<h'=110mm11.5x1200ffb'h'>fA，屬于第一類T型截面sds匚x)105)M=fb'xh=11.5x1200x105x905ucdfI02丿2丿正截面抗彎承載力截面安全=1235KN.M>yM=1202.5KN.M0d222222確定剪力計(jì)算:對(duì)于跨中截面0.5x10-3fbh=0.5x10-3x1.23x250x905=139KN>yU,、=72KNtd00d（0）不需設(shè)置剪力鋼筋的區(qū)段長度（139-72）x62501382x=1382mmc375-72支座中心h/2處截面的最大剪力最大剪力分配：V二72+&39一72）x（6250一5°°）二351KNTOC\o"1-5"\h\zd1382混凝土與鋼筋共同承擔(dān)不少于最大剪力V'的60%，即dV'>0.6V'=0.6x351=210.6KNcsd彎起鋼筋承擔(dān)不多于V'最大剪力的40%,即dV'<0.4V'=0.4x351=140.4KNsbd配置彎起鋼筋：彎起鋼筋的區(qū)段長度Xsb375-351計(jì)算各排彎起鋼筋截面面積:（Xsb375-351計(jì)算各排彎起鋼筋截面面積:3425mm計(jì)算第一排彎起鋼筋截面面積A，取用支座中心h/2處彎起鋼筋承擔(dān)的剪力值：sb1=V'=140.4KNsb1sb第一排彎起鋼筋擬用232,f=280MPa，該彎起鋼筋截面面積需要量為sd人1333.33xV1333.33x140.4門“，A'=鈕=945.6mm2sb1fsin45。280x0.707sd232鋼筋實(shí)際截面積A=1608mm2>A'=945.6mm2滿足抗剪要求，其彎起點(diǎn)Bsb1sb1彎終點(diǎn)在支座中心A截面處，彎起鋼筋與主筋的夾角8=45。彎起點(diǎn)B至點(diǎn)A的距離為…25.135.8crcrc35.8).__AB=1000—56+++35+35.8+=824.85mm(222丿二排擬232=(3425-824.85)x140.4124.8KNsb23425-500人1333.33xV1333.33x124.8，A'=4=840.6mm2sb2fsin45。280x0.707sdBC=AB=824.85mm三排擬232TOC\o"1-5"\h\zV_(3425-824.85-824.85)x140.4巧2KNsb3_3425-500.人1333.33xV1333.33x85.2cA'__573?8mm2sb3fsin45。280x0.707sd/251358358\CD_1000-56+——+^+35+35.8+35.8+_789.05mm四排擬216“(3425-824.85-824.85-789.05)x140.4…“「V==47.34KNsb43425-500A'sb4=A'sb4=318.8mm2280x0.707擬216鋼筋實(shí)際截面積A=402mm2>A'=318.8mm2,滿足抗剪要求sb4sb4(251184184ADE=1000-56+^+^+35+35.8+35.8+=806.45mm(222丿五排“(3425-824.85-824.85-789.05-806.45)x140.4oV==8.6KNsb53425-500人1333.33x8.6—A==57.9mm2sb5280x0.707(251184184AEF=1000-56+^+^+35+35.8+35.8+18.4+——=788.05mm(222丿四排擬216“(3425-824.85-824.85-789.05)x140.4…“「V==47.34KNsb43425-500A'sb4=A'sb4=318.8mm2280x0.707擬216鋼筋實(shí)際截面積A=402mm2>A'=318.8mm2,滿足抗剪要求sb4sb4(251184184ADE=1000-56+^+^+35+35.8+35.8+=806.45mm(222丿五排“(3425-824.85-824.85-789.05-806.45)x140.4o““V==8.6KNsb53425-500人1333.33x8.6A'==57.9mm2sb5280x0.707(251184184AEF=1000-56+^+^+35+35.8+35.8+18.4+——=788.05mm(222丿第五排彎起鋼筋彎起點(diǎn)F至支座中心A的距離為AF=AB+BC+CD+DE+EF824.85+824.85+789.05+806.45+788.05=4033.25>X=3425mmsb各排彎起鋼筋的彎起點(diǎn)至跨中界面G的距離x=BG=L/2-AB=6250-824.85=5425.15mmBx=CG=BG-BC=5425.15-824.85=4600.3mmCx=DG=CG-CD=4600.3-789.05=3811.25mmDx=EG=DG-DE=3811.25-806.45=3004.8mmEx=FG=EG-EF=3004.8-788.05=2216.75mmF

各排彎起鋼筋彎起點(diǎn)的設(shè)計(jì)彎矩彎起鋼筋序號(hào)彎起點(diǎn)序號(hào)彎起點(diǎn)至跨中截面距離各彎起點(diǎn)的設(shè)計(jì)彎矩(4x2)M二M,1—dxd(L/2)L2/跨中界面M=M（、二1202.5Gd（L/2）判斷T型截面梁類型fA二280x5181二1450.7KNcdsfb'h'二11.5x1200x110二1518KNcdfffb'h'>fA屬于一類T型截面cdffcds2229.65各梁段抵抗彎矩計(jì)算表梁段符號(hào)主筋截面積截面有效高度混凝土受壓區(qū)高度系數(shù)1-0.5各梁段抵抗彎矩各層縱向鋼筋的充分利