基础工程课程设计指导书

一、桩基础设设计说1.1-11.1-1所示该桥梁为等跨度~m7m+2×1.0m，双车道。桥2：墩帽宽b546cmd52cm；墩身坡度：图1.1-2设计等级为公路-II3.0kN/m2R号桥墩的地基 1.1-3（单位1.1-1：1.1-1况＃土1＃土1＃土1黏土黏土黏土＃黏土＃黏土＃黏土水文情况：高水位：42.0；施工水位：132.m；常水位：132.m；一般冲刷深度：河底一下1.505.0。1.1-2土粒空隙比饱和度液限塑限8.1×10-黏5.3×10-黏4.3×10-10.35m；2风力强度：1.25kPa（1.5m计桩基础计算。由设计资料中所给的土层的相关资料，通过土力学相关公式，计算如下（13#为例已知ds=2.71e=0.863Sr=0.96ωL31.3ωp=25.6φ=23。Iω

（1-

ω=mw100%（1- ω srd=ms（1-3，S=Vw（1-4，e=Vv（1-srVs 2（1-3（1-4（1-ω=mw 100%=mwSre100%=Sre100%=0.960.863 dsVs

Vwds

Iω

=30.57-25.6 ω

γ=msg+Vvρwg(1-6)，γ'=msg-Vvρwg（1- 3（1-4（1-

=msg+Vvρwg=dsVsρwg+VvρwgVsρwg(ds γ'=msg-VsρwgdsVsρwgVsρwgVsρwg(ds Vsρwg(dsγsat= =dse Vsρwg(dsV

dsγsat=ds

γ=19.179(kN/m3

ds1

γ'=9.179(kN/m3γ=γ 2.1-1土层编土层层厚内摩擦角()比e液性饱和 基本承载力[fa]黏土黏黏2.0m。1m。墩身的容重取24.5kN/m3,计算出桥墩的体积，然后计算墩身自承台容重取24.5kN/m3，计算出承台体积，然后计算其自1.0.75qkPk。T2F2.2-1合序作用名水平力弯矩M（kN1汽人2两孔活载满布汽人3两孔活载满布汽人4两孔活汽人567垂直桥891.0m，采用钻孔灌注桩。桩数根据承台的平面尺寸及有关布桩的要求综合考9根的多排桩，不需要验算桩基础整体的承载力。（具体方法可参考施工二、沉井基础设计(根据自己的班级和学号，参照下例进行设计计算设计说1.1-12：墩帽宽b546cmd52cm；墩身坡度：图1.1-2设计等级为公路-II3.0kN/m2R号桥墩的地基 1.1-3（单位1.1-1：1.1-1况＃黏1＃黏1＃黏1黏土黏土黏土＃黏土＃黏土＃黏土水文情况：高水位：42.0；施工水位：132.m；常水位：132.m；一般冲刷深度：河底一下1.505.0。1.1-2土粒空隙比饱和度液限塑限8.1×10-黏5.3×10-黏4.3×10-10.35m；2风力强度：1.25kPa（1.5m计。由设计资料中所给的土层的相关资料，通过土力学相关公式，计算如下（13#为例已知ds=2.71e=0.863Sr=0.96ωL31.3ωp=25.6φ=23。Iω

（1-

ω=mw100%（1- ω srd=ms（1-3，S=Vw（1-4，e=Vv（1-srVs 2（1-3（1-4（1-ω=mw 100%=mwSre100%=Sre100%=0.960.863 dsVs

Vwds

Iω

=30.57-25.6 ω

γ=msg+Vvρwg(1-6)，γ'=msg-Vvρwg（1- 3（1-4（1-

=msg+Vvρwg=dsVsρwg+VvρwgVsρwg(ds γ'=msg-VsρwgdsVsρwgVsρwgVsρwg(ds Vsρwg(dsγsat= =dse Vsρwg(dsV

dsγsat=ds

γ=19.179(kN/m3

ds1

γ'=9.179(kN/m3γ=γ 2.1-1土层土层内擦(孔隙e液性指IL饱和重度γsat与井壁的摩阻f基本承载[fa]黏沙土C30C25局部冲刷深度hm130124.55.5m，由《公路桥涵地基与基础设计规范（JTGD63-2007）4.1.1-62h=130-124.5+2=7.5mR2-11m13#黏沙土，2.5m4#黏土，再往下为2.2-22.2-1寸2.2-2寸11、刃脚自重：取γ=25kN111x=[0.151.510.15+11.51.2(0.15+1

1V[2π(2.610.455)3.062]1.125122γ=24.5kN2

2.3-12F1.35(4-1.5)-22V(2π2.6123.06)3.255233γ=24.5kN3V=[0.85+1(0.1+0.8)0.7]2.52+10.40.44=11.1938(m3 44γ=24.5kN4444V(2π455γ=24.5kN55V[π1.8623.062]1.5566γ=24.5kN6的封底混凝土厚度取4m。66 G6V6γ6=56.95177γ=20kN7V(π1.262+2.523.06-0.82.52-410.40.4)2.5=25.907(m3 G7V7γ725.90720518.14(kNGG1G2G3G4SV(π2.6125.22S272.596(m3F=γ水VS10272.5961

N12927783(kNV墩=[(5.46-2.4GG1G2G3G4N3G1G2G32的均布荷载标准值及集中荷载标准值均为公路—0.75倍。qk=0.7510.5=7.875(kN/P=0.75[360-180(29-k

N4(20717.8750.5M40.35636.8625222.902(kNmNN528.37.875207221273.725(kNM5MN628.37.87522070.5207.5756.225(kNM60.3520772.45(kNN72128.30.5384.9(kNM70.35N729.715(kNN82128.33169.8(kN)M8T0.25T20.259022.5(kNM922.515.2342(kN

M94515.2684(kNT2FμW0.05272939.15(kNM1039.1515.72P1.25kN墩帽F1.255.460.523.549(kNM3.549(15.2+0.52/2)=54.868(kN墩身F1.25(5.266.38113.22M=96.03[(25.26+6.58)13.2+2]=802.305(kNm)3(5.26+6.58)墩帽F1.252.40.52M1.56(15.2+0.52/2)=24.118(kN墩身F1.25(2.23.5215.212M=54.34[(25.26+6.58)13.2+2]=453.996(kNm)3(5.26+6.58)F1.251.529M(1.5/215.2)54.375867.28(kNT41.56+54.34+54.375110.275(kN2.2-1合序作用名水平力弯矩M（kN1汽人2两孔活载满布汽人3两孔活载满布汽人4两孔活汽人567垂直桥8上部恒N .725169.815608.7HxHyMy=1345.395(kN2MxHxHyMxMy=1345.395(kN3MyHxHyGG1G2G3G'(VVV

T=125+2.528+4.532 T[(π5.2223.06)4(π4.8223.06)4]29.875 G 不排水下沉时：K

[fa]=[fa0]+K1γ1(b-2)+K2γ2(h-

（5-根据地质资料，查表得：[fa0]=407.48K10K22.5

=NMxM

（5-Aπ(5.22)2(8.282 5.22 Ix=64

5.22 Iy=64

W=13.065.222+π5.223 W=13.0625.22+π5.223

y N .725169.815608.7HxHyMy=1345.395(kN

=NMxM = 5225+1472.608+37. =569.97(kPa)<[fa2、顺桥向Mx最大时HxHyMxMy=1345.395(kN

=NMxM = 30635+1725.225+37. =559.722(kPa)<[fap=6Hz(z-

（5- βbh2(4λ-0其中：z= 0，d0

WW2βb1h(3λ-

， kf=10.1d/B10.15.22/8.280.937λ=Ne+Hl

1472.60810.61(m)（竖向力最大λ=Ne+Hl βChmh

1725.225

故βbh3A 0d

15.8282β(3λ- 2βbh2(4λ-0z= 02βb1h(3λ-zh=0.833m

=6138.729

z=h=2.5m

p=6138.7292.5(2.723 时， 时，z=3 h

4(cosφ

3htanz=h=2.5m时，

4(γhtanφ+c)η

1η=1.0η=1.0φ=18.5γ=20.582kN/m3 4

( (

tan18.5+60)11=262.76(kPa)>ph/34(γhtanφ+c)ηη

12 经接上，则刃脚悬臂端作用的分配系数α为： α = =1.958>1，所以取α=11h4 1tan2

16)2W2(132126)1060(kN由于采用排水施工的施工方法，在验算刃脚向外挠曲时，采用取（50%加土压力）70%两者中较小值。1212

4570%26.95358.453(kN/70%10(132127.5126)1.555.125(kN)2EWT0.5E0.51(26.95343.1262或： 17.52K。G1.125253.25524.53.724.52.6-1RVGT198.520.5(132126)43.1260.5133.831(kNV2

2a+bU

tan(α-β)=1.2133.831tan(51.3420.15+1.2

16)

t2+at2a2

6

Va

=2aR

2

R a+2

2a+b

20.15 V2RV0.2RVx=1[V

12+V2(a+3)]=R 2+0.8RV

3 M

W)

W)]h2(E2W2)+(E1W1

3

W

W =55.1251285.126+58.453 =43.9(kNRV

133.831(1.350.455)29.44(kN2MG1.1251.5250.229.28(kNMT17.521.35/211.826(kNM088.82443.929.449.2811.82676.91(kNN0RVF1γ1133.8311.12525105.706(kNe=M0

σ=N0M0105.70676.91478.51(kPa)<fcd/γ0

/γ02.6-2意W1(1421221.5)10185(kNW2(142122)10200(kN1E=20.582(1301221.5)tan21

18.5)69.33(kN/m)2E=20.582(130122)tan22

18.5)85.33(kN/m)PM

W)

W)]h2(E2W2)+(E1W1

3

W

W T0.5E0.51.5(85.33+69.332或：T

421.3528.35(kN2MG1.125250.226.19(kNM0396.99528.356.19374.835(kNN0TG421.1252513.875(kNQ

Fπ(5.2222.522)/43.065.222.612.522σ=P1137.62

井壁横向受力的最不利位置是在沉井沉至设计高程时，这时刃脚根部以上一段（1.2m）2.6-3意1122221E=20.582(1301221.51.25)tan21

18.5)56(kN/m2)2E=20.582(1301221.5)tan22

18.5)69.33(kN/m2)2E=20.582(130122)tan22

18.5)85.33(kN/m2)22L(0.25L3πrL23r2Lπr2ξ= 1.53(0.251.533+π1.9531.532+31.95321.53+π1.9532= 1.532+π1.9531.53+20.67L3πrL24r2L L2πrL2r0.671.533+π1.9531.532+41.95321.53+1.57 1.532+π1.9531.53+2=3.313(m20.33L31.57rL2 2L0.331.533+1.571.9531.532+2 21.53+πL2πrL2r 2L1.532+π1.9531.53+2 21.53+πNpξρη

1.633.313

40.236(kNN12N240.23680.47(kNN2pr=694.351.953=1356.07(kN1Mpξδ1ρη694.351.632.1051.563.313716.68(kN1

M2M1NLp

2

M3

N(Lr)pL(122σmax=N2M1

716.68

2491.8(kPa)<fcd

2.6.32.6-4取q

2.6-5l1=0.7l=0.7q=G1G2= 2

22

Ma=2ql2=2141.841.242M1ql2M=18 a

Ra=2ql=2141.84 QRaql2587.22141.84 q'=(1.35411.1251.5)2 1'2 max=8q

=10.9355.22=1 Qmax=8qB=810.935A1.35411.351.521.3544/211.351.5y= 3I11.3543

σ=My486.212.38

τ=1.5Qm1.5411.05A

(13212210P569.97100

qk100

π2.1625.22

λ=Ly=6.38 qL xM=kx x

My

qkq

取2计算跨度为3.726.38（按照刃脚高度一半处的跨度计算λ=Lx=3.72 Mx0.0844My0.0232。xxyyμ16Mx=738.852+597.39/6=838.417(kN 16

τ=632.65.34

π1.8623.06Lx=3.72 Mx0.0806My0.0249。xxyyμ16Mx=548.99+459.03/6=625.495(kNσ=6