边坡桩基础稳定性计算书计算依据：1、《建筑基坑支护技术规程》JGJ120-2012一、参数信息1.基坑基本参数土类型粉土或砂土厚度h(m) 4 重度γ(kN/m^3) 18 浮重度γmi(kN/m^3) 8 粘聚力C(kPa) 10 内摩擦角φ(°) 30 土类型粘性土厚度h(m) 10 重度γ(kN/m^3) 21 浮重度γmi(kN/m^3) 11 粘聚力C(kPa) 8 内摩擦角φ(°) 203.荷载参数边坡桩基稳定性二、桩侧土压力计算1、水平荷载（1）、主动土压力系数：K a1=tan2（45°- φ1/2）= tan2（45-30/2）=0.333；K a2=tan2（45°- φ2/2）= tan2（45-30/2）=0.333；K a3=tan2（45°- φ3/2）= tan2（45-30/2）=0.333；K a4=tan2（45°- φ4/2）= tan2（45-30/2）=0.333；K a5=tan2（45°- φ5/2）= tan2（45-20/2）=0.49；K a6=tan2（45°- φ6/2）= tan2（45-20/2）=0.49；（2）、土压力、地下水以及地面附加荷载产生的水平荷载：第1层土：0 ~ 1米；（未与桩接触）第2层土：1 ~ 2米；（未与桩接触）第3层土：2 ~ 3米；H3' = ∑γi h i/γ3 = 36/18 = 2；σa3上= [γ3H3'+P1+P2a2/(a2+2l2)]K a3-2c3K a30.5 = [18×2+10+2.5]×0.333-2×10×0.3330.5 = 4.62kN/m；σa3下= [γ3(H3'+h3)+P1+P2a2/(a2+2l2)]K a3-2c3K a30.5= [18×(2+1)+10+2.5]×0.333-2×10×0.3330.5 = 10.62kN/m；第4层土：3 ~ 4米；H4' = ∑γi h i/γ4' = 54/8 = 6.75；σa4上= [γ4'H4'+P1+P2a2/(a2+2l2)]K a4-2c4K a40.5= [8×6.75+10+2.5]×0.333-2×10×0.3330.5 = 10.62kN/m；σa4下= [γ4'H4'+P1+P2a2/(a2+2l2)]K a4-2c4K a40.5+γ4'h4K a4+γw h4' = [8×6.75+10+2.5]×0.333-2×10×0.3330.5+8×1×0.333+10×1 = 23.286kN/m；第5层土：4 ~ 5米；H5' = ∑γi h i/γ5' = 62/11 = 5.636；σa5上= [γ5'H5'+P1+P2a2/(a2+2l2)]K a5-2c5K a50.5+γw h4' = [11×5.636+10+2.5]×0.49-2×8×0.490.5+10×1 = 35.323kN/m；σa5下= [γ5'H5'+P1+P2a2/(a2+2l2)]K a5-2c5K a50.5+γ5'h5K a5+γw h5' = [11×5.636+10+2.5]×0.49-2×8×0.490.5+11×1×0.49+10×2 = 50.717kN/m；第6层土：5 ~ 9米；H6' = ∑γi h i/γ6' = 73/11 = 6.636；σa6上= [γ6'H6'+P1]K a6-2c6K a60.5+γw h5' = [11×6.636+10]×0.49-2×8×0.490.5+10×2 = 49.491kN/m；σa6下= [γ6'H6'+P1]K a6-2c6K a60.5+γ6'h6K a6+γw h6' = [11×6.636+10]×0.49-2×8×0.490.5+11×4×0.49+10×6 = 111.064kN/m；（3）、水平荷载：第1层土：E a1=0kN/m；第2层土：E a2=0kN/m；第3层土：E a3=h3×(σa3上+σa3下)/2=1×(4.62+10.62)/2=7.62kN/m；作用位置：h a3=h3(2σa3上+σa3下)/(3σa3上+3σa3 )+∑h i=1×(2×4.62+10.62)/(3×4.62+3×10.62)+6=6.434m；下第4层土：E a4=h4×(σa4上+σa4下)/2=1×(10.62+23.286)/2=16.953kN/m；作用位置：h a4=h4(2σa4上+σa4下)/(3σa4上+3σa4)+∑h i=1×(2×10.62+23.286)/(3×10.62+3×23.286)+5=5.438m；下第5层土：E a5=h5×(σa5上+σa5下)/2=1×(35.323+50.717)/2=43.02kN/m；作用位置：h a5=h5(2σa5上+σa5下)/(3σa5上+3σa5)+∑h i=1×(2×35.323+50.717)/(3×35.323+3×50.717)+4=4.47m；下第6层土：E a6=h6×(σa6上+σa6下)/2=4×(49.491+111.064)/2=321.109kN/m；作用位置：h a6=h6(2σa6上+σa6下)/(3σa6上+3σa6)+∑h i=4×(2×49.491+111.064)/(3×49.491+3×111.064)+0=1.744m；下土压力合力：E a= ΣE ai= 7.62+16.953+43.02+321.109=388.701kN/m；合力作用点：h a= Σh i E ai/E a= (7.62×6.434+16.953×5.438+43.02×4.47+321.109×1.744)/388.701=2.299m；2、水平抗力计算（1）、被动土压力系数：K p1=tan2（45°+ φ1/2）= tan2（45+20/2）=2.04；K p2=tan2（45°+ φ2/2）= tan2（45+20/2）=2.04；（2）、土压力、地下水产生的水平荷载：第1层土：4 ~ 5米；σp1上= 2c1K p10.5 = 2×8×2.040.5 = 22.85kN/m；σp1下= γ1h1K p1+2c1K p10.5 = 21×1×2.04+2×8×2.040.5 = 65.682kN/m；第2层土：5 ~ 9米；H2' = ∑γi h i/γ2' = 21/11 = 1.909；σa2上= γ2'H2'K p2+2c2K p20.5 = 11×1.909×2.04+2×8×2.040.5 = 65.682kN/m；σa2下= γ2'H2'K p2+2c2K p20.5+γ2'h2K p2+γw h2' = 11×1.909×2.04+2×8×2.040.5+11×4×2.04+10×4 = 195.425kN/m；（3）、水平荷载：第1层土：E p1=h1×(σp1上+σp1下)/2=1×(22.85+65.682)/2=44.266kN/m；作用位置：h p1=h1(2σp1上+σp1下)/(3σp1上+3σp1 )+∑h i=1×(2×22.85+65.682)/(3×22.85+3×65.682)+4=4.419m；下第2层土：E p2=h2×(σp2上+σp2下)/2=4×(65.682+195.425)/2=522.214kN/m；作用位置：h p2=h2(2σp2上+σp2下)/(3σp2上+3σp2)+∑h i=4×(2×65.682+195.425)/(3×65.682+3×195.425)+0=1.669m；下土压力合力：E p= ΣE pi= 44.266+522.214=566.48kN/m；合力作用点：h p= Σh i E pi/E p= (44.266×4.419+522.214×1.669)/566.48=1.884m；三、桩侧弯矩计算1.主动土压力对桩底的弯矩M1 = 0.7×0.6×388.701×2.299 = 375.329kN·m；2.被动土压力对桩底的弯矩M2 = 0.6×566.48×1.884 = 640.24kN·m；3.支撑对桩底弯矩M3 = 170kN·m；四、基础稳定性计算M3+M2≥K(M+M1)170+640.24=810.24kN·m ≥ 1.2×(100+375.329)=570.395kN·m；塔吊稳定性满足要求！。