鉆孔灌注樁計(jì)算書

鉆孔灌注樁計(jì)算書,,,,,,,,,,,

一、已知條件,,,,,,,,,,,

天然地基承載力特征值fak(kPa),,,,800,,,,,,,

"處理后復(fù)合地基承載力特征值fsp,k(kPa)",,,,800,,,,,,,

處理后復(fù)合地基壓縮模量Es(MPa),,,,50,,,,,,,

基礎(chǔ)埋深d(m):,,地面下,23.00,有效埋深,21.00,,,,,,

基礎(chǔ)型式:,,筏基,,,基礎(chǔ)寬度b(m):,,,1.80,長度l(m):,,10.00

地層參數(shù)：,,,,,,,,,,,

地層編號(hào),地層名稱,側(cè)阻力特征值qs(kPa),端阻力特征值qp(kPa),重度γ(kN/m3),壓縮摸量Esi(MPa),厚度(m),厚度(m),厚度(m),厚度(m),厚度(m),厚度(m)

2,,20.0,,18.4,11.2,4.50,,,,,

3,,200.0,,26.0,22.00,4.50,,,,,

4,,200.0,,26.0,32.00,8.50,,,,,

5,,300.0,,26.4,25.00,,,,,,

6,,0.0,,0.0,0.00,0.00,,,,,

7,,0.0,,,,0.00,,,,,

8,,0.0,,,,0.00,,,,,

9,,0.0,,,,0.00,,,,,

10,,0.0,,,,0.00,,,,,

,,,1200,24.05,各孔樁長,17.50,0.00,0.00,0.00,0.00,0.00

,,,,,各孔編號(hào),47,50,51,55,56,57

樁端土強(qiáng)度調(diào)整系數(shù)：,,,α=,1.00,,樁間土強(qiáng)度調(diào)整系數(shù)：,,,,β=,0.75

二、設(shè)計(jì),,π=,3.1415926,,,,,,,,

1、樁身參數(shù)：,,,,,,,,,,,

有效樁長Lp(m):,,17.5,樁徑D(m):,,1.80,,,,,,

周長Up(m):,,5.65,面積Ap(m2):,,2.54469,,,,,,

2、單樁承載力特征值：,,,,,,,,,,,

①根據(jù)樁身側(cè)阻力及端阻力確定單樁承載力特征值Ra(kN),,,,,,,,,,,

Ra=α·qp·Ap+Up·∑qsi·Li,,,,,,,,,,,

,各孔編號(hào),47,50,51,55,56,,57,,,

,Ra＝,18265,#VALUE!,#VALUE!,#VALUE!,#VALUE!,,#VALUE!,,,

②根據(jù)樁體強(qiáng)度確定單樁承載力特征值Ra'(kN),,,,,,,,,,,

fcu≥3Ra/Ap,,,,,,,,,,,

砼立方體抗壓強(qiáng)度平均值fcu(kPa):,,,,30000,混凝土等級(jí)C,,30,,,,

,,,Ra≤,25446.9,kN,,,,,,

綜合①、②取其中小值得,,,,,,,,,,,

最終單樁承載力特征值計(jì)算采用值Ra=,,,,,450,kN,,,,,

3、置換率：,,,,,,,,,,,

"fsp,k=m·Ra/Ap+β·(1-m)·fsk",,,,,,,,,,,

經(jīng)計(jì)算得：,,m=,-0.473,,,,,,,,

4、樁距：,,正方形布置,1,正三角形：,,,,,,,

不大于sd(m)=,,#REF!,,,,,,,,,

實(shí)際應(yīng)用sd(m)=,,1.30,,實(shí)際置換率m(%)=,,150.50,,,,,

5、實(shí)際所需單樁承載力特征值：,,,,,,,,,,,

"Ra=[fsp,k-β(1-m)fsk]·Ap/m",,,,,,,,,,,

,Ra=,1865,kN,,,,,,,,

6、實(shí)際復(fù)合地基理論特征值：,,,,,,,,,,,

,"fsp,k=",-37,kPa,,,復(fù)合地基強(qiáng)度不滿足要求,,,,,

7、復(fù)合土層壓縮模量（各復(fù)合土層加權(quán)值）：,,,,,,,,,,,

,樁間土的壓縮模量ES=,,,24.08,MPa,,,,,,

,復(fù)合土層的壓縮模量Esp=,,,-1.11,MPa,復(fù)合地基壓縮模量不滿足要求,,,,,

8、下臥層驗(yàn)算（本處指樁端處土層）：,,,,,,,,,,,

下臥層承載力特征值fak'(kPa):,,,,150,擴(kuò)散角θ(○):,,,,,4,

基底深度修正系數(shù)ηd:,,,,1.0,寬度修正系數(shù)ηb:,,,,,0.0,

樁端深度修正系數(shù)ηd:,,,,1.6,寬度修正系數(shù)ηb:,,,,,0.0,

復(fù)合地基經(jīng)修正后的承載力特征值fa(kPa):,,,,,"fsp,k+ηb·γ(b-3)+ηd·γm·(d-0.5)=",,,,,456.09,

樁端處天然土附加壓力值pz(kPa):,,,,,lb(p-pc)/(b+2ztgθ)/（l+2ztgθ)=,,,,,129.37,

樁端處天然土自重壓力值pcz(kPa):,,,,,（Lp+d)×γ=,,,,,925.76,

樁端處天然土總應(yīng)力pz+pcz(kPa):,,,,,pz+pcz=,,,,,1055.13,

下臥層經(jīng)深度修正后的承載力特征值faz(kPa):,,,,,fak'+ηb·γ(b-3)+ηd·γm·(d-0.5)=,,,,,1611.98,

faz與pz+pcz比較結(jié)果:,,,,,,該下臥層強(qiáng)度滿足要求,,,,,

9、軟弱下臥層驗(yàn)算(本工程樁端土下仍存在軟弱土)：,,,,,,,,,,,

軟弱下臥層承載力標(biāo)準(zhǔn)值fak''(kPa):,,,,150,擴(kuò)散角θ(○):,,,,,6,

基礎(chǔ)底面至軟弱下臥層頂面得距離z'(m):,,,,16.0,軟弱下臥層深度修正系數(shù)ηd:,,,,,1.6,

軟弱下臥層頂面處天然土附加壓力值pz'(kPa):,,,,,lb(p-pc)/(b+2ztgθ)/（l+2ztgθ)=,,,,,99.13,

軟弱下臥層頂面處天然土自重壓力值pcz'(kPa):,,,,,（Lp+d)×γ=,,,,,889.69,

軟弱下臥層頂面處天然土總應(yīng)力pz'+pcz'(kPa):,,,,,pz'+pcz'=,,,,,988.82,

軟弱下臥層經(jīng)深度修正后的承載力特征值faz'(kPa):,,,,,fak