第四章：土中应力

1、2021/2/2112021/2/2122021/2/2132021/2/214zcz cz= z 2021/2/215zyxKc0ccM(x,y,z)yxzrczcxcy地面地面02021/2/216zcz cz= z+q 2021/2/217 niiinnczzzzz12211zcz=zcz天然地面天然地面1z12z23z34z4cz=z1z11z1+2z21z1+2z2 + 3z31z1+2z2 + 3z3 + 4z42021/2/2181，h12, h23, h34, h4不透水层不透水层下下上上2021/2/2192021/2/2110Fp2021/2/21112021/2/2112

2、2021/2/21132021/2/21142021/2/2115AFblGFpvG=GAdG=20kN/m3 A=bld2021/2/2116F+Gepminpmax2021/2/2117F+G eelbpmaxpminWMlbGFppminmax)61(minmaxlelbGFpp62blW eGFM)( GFMe2021/2/2118leblGFpp61minmax讨论讨论pmaxpminel/6pmaxpmin0pmaxpmin=0基底压力重分布基底压力重分布2021/2/2119belpGF2321max偏心荷载作用在偏心荷载作用在基底压力分布图基底压力分布图形的形心上形的形心上 b

3、elGFp232max2021/2/2120hppp0ch02122110hhhh2021/2/21212021/2/212211101Hp22202Hp2021/2/2123dp0挖槽卸荷挖槽卸荷建造后总荷建造后总荷2021/2/21242021/2/21252021/2/2126x, z的函数的函数x, y, z的函数的函数2021/2/2127RRzEPRPRzPz1)1 (22)1 (cos2323323253cos22222zzrzyxR2252253112323zPzrzPRzPzM(x,y,z)yxzPo2021/2/21282021/2/21292021/2/2130PazPb

4、ab2021/2/2131iniiiniizPzzP122112zPz2021/2/2132FFzzzyxddyxpzd2/52223)()(),(232021/2/2133dxdyp0荷载微单元2/522230)()(23zyxzdxdypdz0cpz2220z2222222222(2)arctan2()()()plbzzlblzbzlbzzlbzl + b)1(arctan1)1)()12(21222222222nmnmnmnnmnmmncc2021/2/2134zMoIVIIIIIIo oIIIIIIIVp0c4c3c2c1z)(p 2021/2/2135IIIo oo o0c2c1z)

5、(p 2021/2/2136o oo oIIo oIIIIIV0c4c3c2c1z)(p 2021/2/2137o oIo oIIIIIIV0c4c3c2c1z)(p 2021/2/2138tz101p22222t1212(1)1mnnmnnmndxdypbx0dxdyzyxbxzpdz2/5)22230(23t2ct1z200()pp2021/2/2139Azzzrzpzrdrrzp2 0 r 0 2/3220302/522300)(1 )(d23d02/32020)1/1(11przpr2021/2/2140条形基础条形基础理想情况实际情况2021/2/2141222341353)(2223zxzpRzpRdypzdz2021/2/2142220zsz022221 21 24 (441)arctanarctan22(441)16pnnm nmpmmnmm2021/2/21432021/2/2144022) 1() 1()1arctan(arctanpmnnmmnmnnpszbzzxdbpz02223