8.8 beam and frame deflections by complementary virtual work Virtual P system 2PD-人(opndVol Actual D system 人ak,dol-含(awwo】 2amo-2owa】 dep =Mpdx El Pn-2(lw"a 土水工程学院 13 Example D System (Actual Load System) 200kN 50 kN/m à 200kN 600kN +400 Mn=-200x Mp (kN-ml n200x25x2 -1200 (1) 00)=0(-kx20rc-250k+7-W-2w0 2Elo +款-X-20 δMp(kN~ml Mp=· 12* 6MP=-1