D值法例题详解

1、例题：4、已知：框架计算简图，用 D值法计算内力并绘制弯矩图37KNwe74KN80,7KNfCGmsdB va3FLJ mase.lnLJ解：1 ）求各柱的剪力值CDGHLMp 1.5 + 1.7K-2.2862x0.77_1.5 + O.B+1.7 + 1.02x0.6=4.166p 0.8+1.0.K-1.0002x0.9D=236小2 + 2.2S6D- 4 VX C d X2 + 4.166D- L°°° X 0 9 X2 + 1.00012f> -fl T?V1 X12f) -fl力吋X1?f)-n 和fiM3.3x333.3x333.3x33(

2、12 )(12 )(12 )3.3x3.333x3.33.3X3.30 3734V-37 X-12.801.079kN0 4054V-37X -13.90 kN1.079V=10.29kN第层21)=1.079“ 123.3x332.4+1.2 +1.7 +1一02x0.72x0.92.929门口2 + 2.92912()=0416Dx3.3X3.3 12 、工5073.500D=2 + 3 500 12 、3.3x3312 ,=0.5727 X&4心2x0.9d+0.3413x.12 、2；D=1.330x,12 、3 3x3.337+74V=0.5737x 7.E01 330V=3

3、3.4SkN3 3x3 3V=0 4150x=1.33034.73 kN第层24K-=4.0000 60-2.4+L2 K-M.50D0.81 2K-1.500OSZ=1.522Xc 12)r 0.5+ 4.000_D= X 0 ES X2 + 4.00012()-0.4500X3,9x3 9(12 )r 0 5+ 4.500_2+4.50012C) -O.dl54x3.9X3.9(12 )D=0.4570x(12 )3.9x393.9x3 93.9X3.937 + 74 + 807V=0,4500x1.52256 68 kN丫心 37+74 + 80.77=0 fil54 X=1.52271

4、.51kNV=57.5kN3 9x3.92 ）求出各柱的反弯点高度 yhCDGHLM第层=2 286yo=.411= =0. S324yiM1.70=1.0旳=0y-0 41+0+0-0.41yo=O.45yi-01.7+1.00=1. Dy3=DyO.4 5+ 0+0=0.45?=1 000yo=0 350.8J= "0.3000yiW)1.00=1.0旳=0y-0.35+0+0-0.35DCFGJL第层K =2.929yo-0.501 71-0.70S371-0240=1.073=03.9也=L18273=03.3yM) 50+0+ 0=0.50=3.500yo-0.501.7

5、+ 1.01=0.7P41 71=02.4 + 1.0他二 1.072=0%=1,182$3=070.53+0+0 =0.50-1 232yo-0-45 -*-0.3333Yi-O12o=t072=00=1.1 £2$3=070.45+0+0=0.45ABEFJ第层2odoyo=O 553.3o(a0 £4 62y? 03,97-0.55+0=0.55M.5D0yo=O 5501=0.3452ya=07-0.55+0=0.55=1.500yo=O 5750=0. S463yi=0y-0.575+0=0 5753）求各柱的柱端弯矩第三层Mcd=12.80X0.41 X3.3k

6、N -m=17.32 kN -mMdc=12.80X 0.59X3.3 kN m =24.92 kN mMgh=13.90X 0.45X3.3 kN m =20.64 kN mMT3.90X 0.55X3.3 kN m =25.23 kN mMlm=10.29X 0.35X3.3 kN m =11.88 kN mMml=10.29X 0.65X3.3 kN m =22.07 kN m第二层Mbc=34.72 X 0.50X3.3 kN m =57.29 kN mMfg=47.80X 0.50X3.3 kN m =78.87 kN mMcb=57.29 kN mMgh=78.87 kN mMjl

7、=28.48X 0.45X3.3 kN m =42.29 kN mMml=28.48X 0.55X3.3 kN m =51.69 kN m第一层m-mm =99.47 kN - mMb=56.68 Xo.55 X3.9 kN - m =121.6 kN -Mf=77.51 Xo.55 X3.9 kN - m =166.3 kNMa=56.68 X0.45 X 3.9 kN -Me=77.51 XO.45 X3.9 kN - M=57.56 X0.575 X3.9 kNMi =57.56 X 0.425 X 3.9 kN4)求各横梁梁端的弯矩 第三层MDhf Mdc=24.92 kN - m1.

8、5m =136.0 kN m-m =129.1 kN m-m =95.41 kN - mMDhfI 5+0 呂 X25.23 kN0.8-m =16.45 kN - mMFL5+0.8 X25.23 kNMMhf Mmi=22.07 kN - m 第二层MCg= Mc+ Mcb=17.32 kNL7-m =8.776 kN - m-m +57.29 kN - m =24.92 kNMGc=L7 + 1.0 X (20.64+78.87 ) kN - m =62.65 kN -1.0Mgc= 1.7 + 1.0 X (20.64+78.87 ) kN - m =36.86 kN - mMlg=

9、Mlm+ Mlj =11.88 kN m +51.69 kN - m =63.57 kN -第一层Mbf= Mbc+ Mba =57.29 kN - m +99.47 kN - m =156.8 kN -2.4Mfe= 24 + 1.2 X (136.0+78.87 ) kN - m =143.2 kN - m1.2Mfj= 24 + 1.2 X (136.0+78.87 ) kN - m =71.62 kN - mMjf= Mjl+ Mji =42.29 kN - m +95.41 kN - m =137.7 kN -5)绘各横梁与柱的弯矩图(单位：kN - m如下图所示1N80 WA16.45=2523 877617.325729A 13.90KN62.6578.87EE.0774.613£72KN