FLAC模拟隧道开挖支护的实例.doc

FLAC3D3.0在某隧道工程开挖支护中的应用;隧道建模命令流入下：newsetlogonsetlogfileyang.loggenzonradcylp0000p19.000p20500p3008&size42064dim6565rat1111group围岩genzoncshellp0000p16.000p20500p3005.0&size42064dim5.64.65.64.6rat1111group初期支护genzoncshellp0000p15.600p20500p3004.6&size42064dim5.04.05.04.0rat1111group二次衬砌fillgroup原岩genzonradcylp0000p100-8.0p20500p39.000&size42064dim3636rat1111group围岩2genzoncshellp0000p100-3.0p20500p36.000&size42064dim2.65.62.65.6rat1111group仰拱初期支护genzoncshellp0000p100-2.6p20500p35.600&size42064dim2525rat1111group仰拱二次衬砌fillgroup仰拱原岩genzonereflectnormal-100genzoneradtunp0000p14500p20500p30020&size320312dim9898rat1111.1group围岩3genzonreflectdip0ori000rangex09y050z820genzonreflectdip0ori000rangex945y050z020genzonreflectdip90dd270ori000rangex09y050z820genzonreflectdip90dd270ori000rangex09y050z-8-20genzonreflectdip90dd270ori000rangex945y050z-2020genzonbrickp0-450-20p1-450-40p2-4550-20p3450-20&size5206rat1.111group围岩4savetun_model.sav;假设围岩岩体符合mohr-coulomb本构模型，给围岩赋参数命令流如下，;mohr-coulombmodelmodelmohrdefderives_mod1=E_mod1/(2.0*(1.0+p_ratio1))b_mod1=E_mod1/(3.0*(1.0-2.0*p_ratio1))s_mod2=E_mod2/(2.0*(1.0+p_ratio2))b_mod2=E_mod2/(3.0*(1.0-2.0*p_ratio2))endsetE_mod1=0.6e9p_ratio1=0.27E_mod2=0.8e9p_ratio2=0.26derivepropbulkb_mod1shears_mod1cohe1.8e6tens0.8e6fric30rangez4.520propbulkb_mod2shears_mod2cohe2.8e6tens1.0e6fric35rangez-404.5inidens=2300setgrav00-10;boundaryandinitialconditionsapplyszz-1.4e6rangez19.920.1fixzrangez-40.1-39.1fixxrangex-45.1-44.9fixxrangex44.945.1fixyrangey49.950.1histunbalhistgpxdis6.0,0,0histgpzdis0,0,5histgpxdis6.0,50,0histgpzdis0,50,5plothist3solvesavetun_nature.sav;对后面计算而言，模型建立时岩体在开挖前认为位移已经终了，因此需要对位移进行“清零”，而应力可以保留。

假设隧道先开挖上断面，中间不设支护，直到进尺50m，那么此时位移和应力的分布情况可用如下命令流inixdis=0ydis=0zdis=0plotremodelnullrangegroup原岩modelnullrangegroup二次衬砌modelnullrangegroup初期支护setlargehistunbalplothist3solvesavetun_ext1.sav;如果在开挖后适时对隧道进行锚喷混凝土初期支护，该命令流如下：restoretun_nature.savinixdis=0ydis=0zdis=0plotremodelnullrangegroup初期支护modelnullrangegroup二次衬砌modelnullrangegroup原岩step100histunbalplothist3moelrangegroup初期支护propbulk1.33e9shear0.8e9cohe2.2e6tens1.2e6fric32rangez4.57.0x-7.07.0propbulk10.9e9shear8.9e9dens2500rangegroup初期支护setlargesolvesavetun_ext2.sav。