人工挖孔桩承载力特征值抗拔承载力计算-省规范

1、1.桩身承载力设计值计算Q=ApfccRZH1RZH4RZH5RZH6RZH7RZH8RZH9RZH10桩直径12001400160016001800200022002200采用砼等级C25C30C30C30C30C30C30C30对应砼强度设计值11.914.314.314.314.314.314.314.3工作条件系数0.70.70.70.70.70.70.70.7桩身承载力设计值94162321.5E+072E+072E+072.5E+07 3.1E+07 3.8E+07 38031994桩身承载力特征值6974.987 11408.4 14900.8 14900.8 18858.8 2

2、3282.5 28171.8 28171.85桩身承载力设计值（桩直径/2）（桩直径/2）3.14砼强度设计值工作条件系数桩身承载力特征值桩身承载力设计值/1.352.人工挖孔灌注桩承载力计算Ra=qpaAp地基规范（8.5.5-2公式)D18002800300032003600380042004400qpa18001800180018001800180018001800Ap2.54346.15447.0658.0384 10.1736 11.3354 13.8474 15.1976Ra4578.1217232.32119525722.93662543074.5 58159.1 66869.4

3、4取Ra=4500100001230014300180002000023500275003.人工挖孔灌注桩抗拔力计算RZH1RZH712001800D180036003.7685.652qsia6060li44入0.550.55Qsa*qsia*li*入497.376746.064i5.65211.304qsia8080li49入0.850.85Qsa*qsia*li*入1537.3446918.05TukQsa1Qsa22034.727664.11Nk(单桩抗拔承载力特征值)=Tuk/21017.363832.06取Nk=1000KN33104.桩身抗拔计算NfyAs+fpyApy,其中N=

4、3310kNN3310fy300As11033.3实际配筋3222 121605.裂缝宽度验算根据地探报告可知环境类别为二a，最大裂缝宽度限值可取0.2mm18003222As12160Ate2543400te=As/Ate0.004781deq22ftk2.01Nk3310000sk=Nk/As272.2039=1.1-0.65*ftk/(te*sk)0.096087max=cr*sk*(1.9c+0.08deq/te)/Es其中cr=2.7c=50Es=200000max=0.163527(满足）计算裂缝宽度max限值0.2mm，符合要求1.桩身承载力设计值计算Q=Apfcc桩直径8001

5、000120014001600采用砼等级C35C35C35C35C35对应砼强度设计值16.716.716.716.716.7工作条件系数0.70.70.70.70.7桩身承载力设计值5873056917665013214376 17986234 23492224桩身承载力特征值4350.412 6797.519 9788.4267 13323.14 17401.65桩身承载力设计值（桩直径/2）（桩直径/2）3.14砼强度设计值工作条件系数桩身承载力特征值桩身承载力设计值/1.252.灌注桩承载力计算Ra=qpaAp+upqsiali80010001200140016002.5123.143

6、.7684.3965.024qsia6060606060li88888Qsa1=*qsia*li1205.761507.21808.642110.082411.522.5123.143.7684.3965.024qsia8080808080li1515151515Qsa2=*qsia*li3014.437684521.65275.26028.8p11111每边外扩00000D0.811.21.41.6qpa15001500150015001500Ap0.50240.7851.13041.53862.0096Qgpk753.61177.51695.62307.93014.4RaQsa1Qsa2Q

7、gpk4973.766452.78025.849693.18 11454.723.灌注桩抗拔力计算800100012002.5123.143.768qsia606060li888入0.550.550.55Qsa*qsia*li*入663.168828.96994.7522.5123.143.768qsia808080li151515入0.650.650.65Qsa*qsia*li*入1959.362449.22939.04入111每边外扩000D0.811.2qpa000Ap0.50240.7851.1304Qgpk000TukQsa1Qsa22622.5283278.163933.792Nk(单桩抗拔承载力特征值)=Tuk/21311.2641639.08 1966.8964.桩身抗拔计算NfyAs+fpyApy,其中N=930kNN600fy300As2000实际配筋1216 24125.裂缝宽度验算根据地探报告可知环境类别为二a，最大裂缝宽度限值可取0.2mm8001216As2412Ate502400te=As/Ate0.004801deq1ftk2.2Nk600000sk=Nk/As248.7562=1.1-0.65*ftk/(te*sk)-0.09739max=cr*sk*(1.9c+0.08deq/te)/Es其中cr=2.7c=50Es=200000max=