1静定结构与超静定结构静力常用计算公式一、短柱、长柱压应力极限荷载计算公式1、短柱压应力计算公式荷载作用点轴方向荷载AFbhF偏心荷载)1(21xYiyeAFWMAF)1(22xYiyeAFWMAF)61(2,1hebhF偏心荷载)1(22xyyxxxyYiyeixeAFIxMIxMAF)661(behebhFyx长短柱分界点如何界定?2、长柱方程式及极限荷载计算公式支座形式图示方程式极限荷载一般式n=1两端铰支β=1yadxyd222axBaxAysincosyFMEIFa,2EIln222EIl22一端自由他端固定β=2yadxyd222axBaxAysincosEIln2224)12(EIl2242yFMEIFa,2两端固定β=0.50)(22FMyadxydAFMaxBaxAyAsincosAMyFMEIFa,2EIl224EIl224一端铰支他端固定β=0.75)(222xlEIQyadxyd)(sincosxlFQaxBaxAy水平荷载QEIFa,2——EIl227778.1注:压杆稳定临界承载能力计算公式:EIlPcr22)(二、单跨梁的反力、剪力、弯矩、挠度计算公式1、简支梁的反力、剪力、弯矩、挠度计算公式荷载形式M图V图反力2FRRBALFbRALFaRB2qLRRBA4qLRRBA剪力VA=RAVB=-RBVA=RAVB=-RBVA=RAVB=-RBVA=RAVB=-RB3弯矩4maxFLMLFabMmax82maxqLM122maxqLM挠度EIFL483max若a>b时,3)2(932maxabaEILFb(在)2(3baax处)EIqL84maxEIqL1204max注:1、弯矩符号以梁截面下翼缘手拉为正(+),反之为负(—)。2、剪力符号以绕梁截面顺时针方向为正(+),反之为负(—)。2、悬臂梁的反力、剪力、弯矩、挠度计算公式荷载形式M图V图反力RB=FRB=-FRB=qLRB=qa剪力VB=-RBVB=-RBVB=-RBVB=-RB弯矩MB=-FLMB=-Fb221qLMB)2(2aLqaMB挠度EIFLA33)3(62bLEIFbAEIFLA84)43(24434bLbLEIqA3、外伸梁的反力、剪力、弯矩、挠度计算公式荷载形式M图V图4反力)1(LaFRALFaRB)32(2LaFRALFaRB232)1(2LaqLRA)1(222LaqLRB)683(822LaLaqLRA)65(822LaqLRB剪力VA左=-FVB=-RBVA左=-FVA右=-RBVA左=-qaVA右=RA-qaVB=-RBVA左=-qaVA左=)65(822LaqL弯矩Mmax=-FaMA=-FaMB=Fa/222qaMA)21(822222LaqLMqaMBA挠度)(32maxaLEIFaEIFaLaLEIFaC27)43(122max)34(24323aLaLEIqaC)66(48323aLaLEIqaC4、一端固定、一端简支梁de反力、剪力、弯矩、挠度计算公式荷载形式M图V图反力)3(222LbLFbRA)3(222LaLFaRBRA=RB=qL21qLRqLRBA8583剪力VA=RAVB=-RB)21(2LxqLVxVA=RAVB=-RB弯矩)3(222maxLbLFabMMA=MB=-122qLM中=2241qL2max1289qLM挠度——EIqL384max4EIqL4max00542.0三、等截面等跨连续梁的弯矩、剪力、挠度计算系数及公式51、二等跨连续梁的弯矩、剪力、挠度计算系数及公式荷载图示弯矩系数KM剪力系数KV挠度系数KωM1中MB支VAVB左、VB右ω1中静载活载最大活载最小0.0700.096-0.032-0.125-0.125——0.3750.437——-0.6250.625-0.6250.625——0.5210.192-0.391静载活载最大活载最小0.1560.203-0.047-0.188-0.188——0.3120.406——-0.6880.688-0.6880.688——0.9111.497-0.586静载活载最大活载最小0.2220.278-0.084-0.3330.333——0.6670.833——-1.3331.333-1.3331.333——1.4662.508-1.042注:1、均布荷载作用下:2qLKMM,qLKVV,EIqLK1004;集中荷载作用下:FLKMM,FKVV,EIFLK1003;2、支座反力等于该支座左右截面剪力的绝对值之和;3、求跨中负弯矩及反挠度时,可查用上表“活载最小”一项的系数,但也要与静载引起的弯矩(或挠度)相组合。4、求跨中最大正弯矩及最大挠度时,该跨应满布活荷载,相邻跨为空载;求支座最大负弯矩及最大剪力时,该支座相邻两跨应满布荷载,即查用上表中“荷载最大”一项的系数,并与静载引起的弯矩(剪力或挠度)相组合。2、三等跨连续梁的弯矩、剪力、挠度计算系数及公式荷载图示弯矩系数KM剪力系数KV挠度系数KωM1中M2中MB支VAVB左、VB右ω1中ω2中静载活载最大活载最小0.0800.101-0.0250.0250.075-0.050-0.100-0.1770.017-0.4000.450——-0.6000.500-0.6170.583——0.6770.990-0.3130.0520.677-0.625静载活载最大活载最小0.1750.213-0.0380.1000.175-0.075-0.150-0.1750.0250.3500.425——-0.6500.500-0.6750.625——1.1461.615-0.4690.2081.146-0.9376注:1、2、3条同上述二等跨连续梁;4、求某跨的跨中最大正弯矩及最大挠度时,该跨应满布活荷载,其余每隔一跨满布活荷载;求某支座的最大负弯矩及最大剪力时,该支座相邻两跨应满布活荷载,其余每隔一跨满布活荷载,即查上表中“活载最大”一项的系数,并与静载引起的弯矩(剪力或挠度)相组合。3、四等跨连续梁的的弯矩、剪力、挠度计算系数及公式荷载图示弯矩系数KM剪力系数KV挠度系数KωM1中M2中MB支MC支VAVB左、VB右Vc左、Vc右ω1中ω2中见图a静载活载最大活载最小0.0770.1000.0230.0360.0810.045-0.107-0.1210.013-0.071-0.1070.0180.3930.446——-0.6070.536-0.6200.603——-0.4640.464-0.5710.571——0.6320.967-0.3070.1860.660-0.588见图b静载活载最大活载最小0.1690.2100.0400.1160.183-0.067-0.161-0.1810.020-0.107-0.1610.0200.3390.420——-0.6610.554-0.6810.654——-0.4460.446-0.6070.607——1.0791.581-0.4600.4091,121-0.711注:事项同三跨连续梁。四、不等跨连续梁在均布荷载作用下的弯矩、剪力计算系数及公式1、二跨不等跨连续梁的弯矩、剪力计算系数及公式荷载简图计算公式弯矩M=表中系数×qL12(KN·m)剪力V=表中系数×qL1(KN)静载时活载最不利布置时nM1M2MB最大VAVB左最大VB右最大VaM1最大M2最大VA最大VC最大1.01.11.21.31.40.0700.0650.0600.0530.0470.0700.0900.1110.1330.157-0.125-0.139-0.155-0.175-0.1950.3750.3610.3450.3260.305-0.625-0.639-0.655-0.674-0.6950.6250.6760.7290.7840.839-0.375-0.424-0.471-0.516-0.5610.0960.0970.0980.0990.1000.0960.1140.1340.1560.1790.4330.4400.4430.4460.448-0.438-0.476-0.518-0.558-0.59871.51.61.71.81.92.02.252.50.0400.0330.0260.0190.0130.0080.003——0.1830.2090.2370.2670.2980.3300.4170.513-0.219-0.245-0.274-0.305-0.339-0.375-0.477-0.5940.2810.2550.2260.1950.1610.1250.023-0.094-0.719-0.745-0.774-0.805-0.839-0.875-0.976-1.0940.8960.9531.0111.0691.1281.1881.3371.488-0.604-0.647-0.689-0.731-0.772-0.813-0.913-1.0130.1010.1020.1030.1040.1040.1050.1070.1080.2030.2290.2560.2850.3160.3470.4330.5270.4500.4520.4540.4550.4570.4580.4620.464-0.638-0.677-0.716-0.755-0.794-0.833-0.930-1.0272、三跨不等跨连续梁的弯矩、剪力计算系数及公式荷载简图计算公式弯矩M=表中系数×qL12(KN·m)剪力V=表中系数×qL1(KN)静载时活载最不利布置时nM1M2MB支VAVB左VB右M1最大M2最大MB最大VA最大VB左最大VB右最大0.40.50.60.70.80.91.01.11.21.31.41.51.61.71.81.92.02.252.50.0870.0880.0880.0870.0860.0830.0800.0760.0720.0660.0610.0550.0490.0430.0360.0300.0240.0110.002-0.063-0.049-0.035-0.021-0.0060.0100.0250.0410.0580.0760.0940.1130.1330.1530.1740.1960.2190.2790.344-0.083-0.080-0.080-0.082-0.086-0.092-0.100-0.110-0.122-0.136-0.151-0.163-0.187-0.203-0.231-0.255-0.281-0.354-0.4330.4170.4200.4200.4130.4140.4080.4000.3900.3780.3650.3490.3320.3130.2920.2690.2450.2190.1460.063-0.583-0.580-0.580-0.582-0.586-0.592-0.600-0.610-0.622-0.363-0.651-0.663-0.687-0.708-0.731-0.755-0.781-0.854-0.9380.2000.2500.3000.3500.4000.4500.5000.5500.6000.6500.7000.7500.8000.8500.9000.9501.0001.1251.2500.0890.0920.0940.0960.0980.1000.1010.1030.1040.1050.1060.1070.1070.1080.1090.1090.1100.1110.1120.0150.0220.0310.0400.0510.0630.0750.0890.103