新规公路桥台抗震计算程序

K5+320小桥桩基薄壁桥台计算,,,,,,,,,,,,,,,,

(一)设计资料,,,,,,,,,,,,,,,,

1、总体情况,,,,,,,,,,,,,,,,

,结构重要性系数,,,,γ0=,1.0,,,,,,,,,,

,桥梁计算跨径,,,,l=,16,m,,,,,,,,,

,环境类别,,,,,Ⅰ类,,,,,,,,,,

2、地震资料,,,,,,,,,,,,,,,,

,桥梁抗震设防类别:,,,,,C,类,,,,,,,,,

,地震动峰值加速度,,,,A=,0.10,g,,,,,,,,,

,阻尼比,,,,ξ=,0.05,,,,,,,,,,

3、汽车荷载,,,,,,,,,,,,,,,,

,汽车荷载等级:,,,,,公路Ⅱ级,,,,,,,,,,

,汽车荷载提高或折减系数,,,,,1,,,,,,,,,,

,行驶方向:,,,,,双向行驶,,,,,,,,,,

,设计车道数,,,,,2,,,,,,,,,,

,车道折减系数,,,,,1,,,,,,,,,,

,桥台传递的制动力比例,,,,,0.5,,,,,,,,,,

4、上部构造,,,,,,,,,,,,,,,,

,一孔上部结构重力,,,,,7400,kN,,,,,,,,,

,上部结构混凝土强度等级,,,,,C40,,,,,,,,,,

,上部结构跨中处延米结构重力,,,,G=,15,kN/m,,,,,,,,,

,上部结构跨中截面惯矩,,,,Ic=,0.04,m4,,,,,,,,,

5、桥台尺寸,,,,,,,,,,,,,,,,

,桥梁斜度,,,,,0°,,,,,,,,,,

,桥台正宽度,,,,,13,m,,,,,,,,,

,桥台斜宽度,,,,,13.000,m,,,,,,,,,

,背墙高度,,,,,1.25,m,,,,,,,,,

,背墙顶宽度,,,,,0.4,m,,,,,,,,,

,置搭板背墙高,,,,,0.31,m,,,,,,,,,

,置搭板背墙宽,,,,,0.25,m,,,,,,,,,

,台帽高度,,,,,1.3,m,,,,,,,,,

,台帽宽度,,,,,1.45,m,,,,,,,,,

,台帽支撑宽度,,,,,0.8,m,,,,,,,,,

,台帽前缘帽檐,,,,,0.35,m,,,,,,,,,

,台身高度,,,,,4.08,m,,,,,,,,,

,台身厚度,,,,,0.8,m,,,,,,,,,

,承台高度,,,,,1.6,m,,,,,,,,,

,承台顺桥向宽度,,,,,2.2,m,,,,,,,,,

,台身前缘与承台前缘垂直距离,,,,,0.7,m,,,,,,,,,

,桥台桩基个数,,,,n桩=,4,,,,,,,,,,

,桥台桩径,,,,d=,1.5,m,,,,,,,,,

,桥台桩长,,,,,10,m,,,,,,,,,

,桩基类型,,,,,嵌岩桩,,,,,,,,,,

6、桥头搭板,,,,,,,,,,,,,,,,

,搭板长度,,,,,8,m,,,,,,,,,

,搭板宽度,,,,,13,m,,,,,,,,,

,搭板厚度,,,,,0.3,m,,,,,,,,,

7、支座数据,,,,,,,,,,,,,,,,

,支座中心与背墙前缘线正距离,,,,,0.32,m,,,,,,,,,

,支座种类：,,,,,板式橡胶支座(与混凝土接触),,,,,,,,,,

,支座摩擦系数,,,,μ=,0.3,,,,,,,,,,

,支座+垫石高度,,,,,0.2,m,,,,,,,,,

8、地基及填土,,,,,,,,,,,,,,,,

,桥梁工程场地类别,,,,,Ⅱ类场地,,,,,,,,,,

,地基土的比例系数,,,,m=,30000,kN/m4,,,,,,,,,

,台后土的重力密度,,,,γ=,19,kN/m3,,,,,,,,,

,台后土的内摩擦角,,,,φ=,35,°,,,,,,,,,

9、建筑材料,,,,,,,,,,,,,,,,

,桥台混凝土的重力密度,,,,,25,kN/m3,,,,,,,,,

,台身混凝土强度等级,,,,,C30,,,,,,,,,,

,台身主筋种类,,,,,HRB335,,,,,,,,,,

,台身主筋直径,,,,,25,mm,,,,,,,,,

,台身主筋中心至混凝土表面的距离,,,,,0.06,m,,,,,,,,,

,桩基混凝土强度等级,,,,,C25,,,,,,,,,,

,桩基主筋种类,,,,,HRB335,,,,,,,,,,

,桩基主筋直径,,,,,25,mm,,,,,,,,,

,桩基主筋中心至混凝土表面的距离,,,,,0.075,m,,,,,,,,,

10、其他计算数据,,,,,,,,,,,,,,,,

,是否考虑支撑梁作用,,,,,考虑,,,,,,,,,,

,构件计算长度系数(台身),,,,,2.0,,,,,,,,,,

,构件计算长度系数(桩基),,,,,0.5,,,,,,,,,,

11、技术标准与设计规范,,,,,,,,,,,,,,,,

,1)中华人民共和国行业标准《公路桥涵设计通用规范》(JTGD60—2004),,,,,,,,,,,,,,,

,2)中华人民共和国行业标准《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTGD62—2004),,,,,,,,,,,,,,,

,3)中华人民共和国行业标准《公路桥涵地基与基础设计规范》(JTGD63—2007),,,,,,,,,,,,,,,

,4)中华人民共和国行业推荐性标准《公路桥梁抗震设计细则》(JTG/TB02-01—2008),,,,,,,,,,,,,,,

,,,,,,,,,,,,,,,,,

(二)竖向恒载计算,,,,,,,,,,,,,,,,

1、恒载重力计算,,,,,,,,,,,,,,,,

,1)上部构造恒载反力,,,,,,,,,,,,,,,

,竖向力,,,,P1=,3700,kN,,,,,,,,,

,对台身中心偏心距,,,,e1=,0.27,m,,,,,,,,,

,对承台中心偏心距,,,,e1'=,0.27,m,,,,,,,,,

,2)桥台背墙重,,,,,,,,,,,,,,,

,竖向力,,,,P2=,162.5+,76.4=,238.9,kN,,,,,,,

,对台身中心偏心距,,,,e2=,-0.25,m，,-0.575,m,,,,,,,

,对承台中心偏心距,,,,e2'=,-0.25,m，,-0.575,m,,,,,,,

,3)桥台台帽重,,,,,,,,,,,,,,,

,竖向力,,,,P3=,612.6,kN,,,,,,,,,

,对台身中心偏心距,,,,e3=,0.025,m,,,,,,,,,

,对承台中心偏心距,,,,e3'=,0.025,m,,,,,,,,,

,4)桥台台身重,,,,,,,,,,,,,,,

,竖向力,,,,P4=,1060.8,kN,,,,,,,,,

,对承台中心偏心距,,,,e4=,0,m,,,,,,,,,

,5)桥台承台重,,,,,,,,,,,,,,,

,竖向力,,,,P5=,1144.0,kN,,,,,,,,,

,6)承台上土重,,,,,,,,,,,,,,,

,竖向力,,,,P6=,705.4+,221.3=,926.7,kN,,,,,,,

,对承台中心偏心距,,,,e6=,-0.75,m，,-0.9,m,,,,,,,

,7)桥头搭板反力,,,,,,,,,,,,,,,

,按跨径为搭板长度的0.7倍的简支梁计算,,,,,,,,,,,,,,,

,竖向力,,,,P7=,273.0,kN,,,,,,,,,

,对台身中心偏心距,,,,e7=,-0.575,m,,,,,,,,,

,对承台中心偏心距,,,,e7'=,-0.575,m,,,,,,,,,

2、恒载对各截面所产生的垂直力及弯矩,,,,,,,,,,,,,,,,

,1)对台身底截面,,,,,,,,,,,,,,,

,竖向力,,,,,PⅠ恒=P1+P2+P3+P4+P7=,5885.3,kN,,,,,,,,

,弯矩,,,,,MⅠ恒=P1e1+P2e2+P3e3+P7e7=,772.8,kN·m,,,,,,,,

,2)对承台底截面,,,,,,,,,,,,,,,

,竖向力,,,,,PⅡ恒=P1+P2+P3+P4+P5+P6+P7=,7956.0,kN,,,,,,,,

,弯矩,,,,,,MⅡ恒=P1e1'+P2e2'+P3e3'P4e4+P6e6+P7e7'=,44.5,kN·m,,,,,,,

,,,,,,,,,,,,,,,,,

(三)水平土压力计算,,,,,,,,,,,,,,,,

1、台后填土自重引起的土压力,,,,,,,,,,,,,,,,

,土的内摩擦角,,,,φ=,35°,,,,,,,,,,

,桥台与竖直面的夹角,,,,α=,0°,,,,,,,,,,

,填土表面与水平面的夹角,,,,β=,0°,,,,,,,,,,

,台背与填土间的摩擦角,,,,δ=,φ/2=,17.5°,,,,,,,,,

,主动土压力系数,,,,μ=,,,,=,0.2461,,,,,,

,主动土压力标准值,,,,E=,BμγH2/2,,,,,,,,,,

,土的重力密度,,,,γ=,19,kN/m3,,,,,,,,,

,桥台的计算宽度,,,,B=,13.000,m,,,,,,,,,

,①对台身底截面,,,,,,,,,,,,,,,

,计算土层高度,,,,H1=,6.63,m,,,,,,,,,

,主动土压力,,,,E1=,1336.1,kN,,,,,,,,,

,自计算土层底面算起土压力的着力点,,,,,C1=H1/3=,2.210,m,,,,,,,,

,弯矩,,,,,MEⅠ=E1C1=,2952.8,kN·m,,,,,,,,

,②对承台底截面,,,,,,,,,,,,,,,

,计算土层高度,,,,H2=H1=,6.63,m,,,,,,,,,

,主动土压力,,,,E2=E1=,1336.1,kN,,,,,,,,,

,自计算截面算起土压力的着力点,,,,C2=C1,+1.6=,3.810,m,,,,,,,,

,弯矩,,,,,MEⅡ=E2C2=,5090.6,kN·m,,,,,,,,

2、汽车荷载引起的土压力,,,,,,,,,,,,,,,,

,桥台与竖直面的夹角,,,,α=,0°,,,,,,,,,,

,土的内摩擦角,,,,φ=,35°,,,,,,,,,,

,台背与填土间的摩擦角,,,,δ=,φ/2=,17.5°,,,,,,,,,

,,,,,,ω=α+δ+φ=,52.5°,,,,,,,,,

,破坏棱体破裂面与竖直线间夹角θ,,,,tanθ=,,,,=,0.5835,,,,,,

,填土高度,,,,H=,6.63,m,,,,,,,,,

,破坏棱体长度,,,,,,l0=H(tanα+tanθ)=,3.868,m,,,,,,,

,破棱体上作用轴数,,,,,2轴,,,,,,,,,,

,车道系数,,,,,2,,,,,,,,,,

,车轮的总重力,,,,∑G=,560.0,kN,,,,,,,,,

,桥台横向全宽,,,,B=,13.000,m,,,,,,,,,

,土的重力密度,,,,γ=,19.0,kN/m3,,,,,,,,,

,车辆荷载等代均布土层厚度,,,,,h=∑G/(Bl0γ)=,0.586,m,,,,,,,,

,主动土压力系数,,,,μ=,0.2461,,,,,,,,,,

,主动土压力标准值,,,,E=,BμγHh,,,,,,,,,,

,①对台身底截面,,,,,,,,,,,,,,,

,计算土层高度,,,,H1=,6.63,m,,,,,,,,,

,汽车引起的主动土压力,,,,E1'=,236.2,kN,,,,,,,,,

,自计算土层底面算起土压力的着力点,,,,,C1'=H1/2=,3.315,m,,,,,,,,

,弯矩,,,,,MeⅠ'=E1'C1'=,783.1,kN·m,,,,,,,,

,②对承台底截面,,,,,,,,,,,,,,,

,计算土层高度,,,,H2=H1=,6.63,m,,,,,,,,,

,汽车引起的主动土压力,,,,E2'=E1'=,236.2,kN,,,,,,,,,

,自计算截面算起土压力的着力点,,,,C2'=C1',+1.6=,4.915,m,,,,,,,,

,弯矩,,,,,MeⅡ'=E2'C2'=,1161.0,kN·m,,,,,,,,

,,,,,,,,,,,,,,,,,

(四)汽车荷载计算,,,,,,,,,,,,,,,,

1、汽车荷载反力计算,,,,,,,,,,,,,,,,

,车道荷载的均布荷载标准值,,,,qK=,7.9,kN/m,,,,,,,,,

,车道荷载的集中荷载标准值,,,,PK=,168.0,kN,,,,,,,,,

,车道系数,,,,,2,,,,,,,,,,

,桥梁计算跨径,,,,l=,16,m,,,,,,,,,

,汽车荷载反力,,,,,,P汽=(qKl/2+1.2PK)*车道系数=,529.2,kN,,,,,,,

,对台身中心偏心距,,,,e1=,0.27,m,,,,,,,,,

,对承台中心偏心距,,,,e1'=,0.27,m,,,,,,,,,

,汽车荷载对台身底截面产生的弯矩,,,,,,,,,,,,,,,

,,,,,MⅠ汽=,142.9,kN·m,,,,,,,,,

,汽车荷载对承台底截面产生的弯矩,,,,,,,,,,,,,,,

,,,,,MⅡ汽=,142.9,kN·m,,,,,,,,,

2、汽车冲击力计算,,,,,,,,,,,,,,,,

,上部结构跨中处的单位长度质量,,,,mc=,G/g=,1529.1,kg/m,,,,,,,,

,上部结构混凝土的弹性模量,,,,Ec=,3.25E+10,N/m2,,,,,,,,,

,上部结构跨中截面惯矩,,,,Ic=,0.04,m4,,,,,,,,,

,桥梁计算跨径,,,,l=,16,m,,,,,,,,,

,结构基频,,,,f=,,=,5.66,Hz,,,,,,,

,冲击系数,,,当f＜1.5Hz，μ=0.05,,,,,,,,,,,,

,,,,当1.5Hz≤f≤14Hz，μ=0.1767lnf-0.0157,,,,,,,,,,,,

,,,,当f＞14Hz，μ=0.45,,,,,,,,,,,,

,,,,,μ=,0.291,,,,,,,,,,

,汽车冲击力,,,,P冲=,μP汽=,153.7,kN,,,,,,,,

,汽车冲击力对台身底截面产生的弯矩,,,,,,,,,,,,,,,

,,,,,MⅠ冲=,41.5,kN·m,,,,,,,,,

,汽车冲击力对承台底截面产生的弯矩,,,,,,,,,,,,,,,

,,,,,MⅡ冲=,41.5,kN·m,,,,,,,,,

,,,,,,,,,,,,,,,,,

(五)汽车荷载制动力、支座摩阻力计算,,,,,,,,,,,,,,,,

1、汽车荷载制动力计算,,,,,,,,,,,,,,,,

,车道荷载的均布荷载标准值,,,,qK=,7.9,kN/m,,,,,,,,,

,车道荷载的集中荷载标准值,,,,PK=,168.0,kN,,,,,,,,,

,一个设计车道总重力的10%,,,,,29.4,kN<,90,kN,,,,,,,

,一个设计车道的制动力标准值,,,,,90.0,kN,,,,,,,,,

,同向行驶车道系数,,,,,2,,,,,,,,,,

,多车道的制动力,,,,T=,180.0,kN,,,,,,,,,

,桥台支座传递的制动力,,,,T'=,0.5T=,90.0,kN,,,,,,,,

2、支座摩阻力计算,,,,,,,,,,,,,,,,

,支座摩擦阻系数,,,,μ=,0.30,,,,,,,,,,

,上部构造恒载反力,,,,W=,3700,kN,,,,,,,,,

,支座摩阻力标准值,,,,F=,μW=,1110.0,kN,,,,,,,,

3、制动力或摩阻力对各截面所产生的弯矩计算,,,,,,,,,,,,,,,,

,根据《公路桥涵设计通用规范》(JTGD60—2004)第4.3.6条，支座传递的制动力不应大于其摩阻力。,,,,,,,,,,,,,,,

,纵向水平力取“汽车制动力”与“支座摩阻力”小的值计算。,,,,,,,,,,,,,,,

,,,,,H=,90.0,kN,,,,,,,,,

,①对台身底截面,,,,,,,,,,,,,,,

,制动力的着力点距计算截面,,,,,5.58,m,,,,,,,,,

,弯矩,,,,MT1=,502.2,kN·m,,,,,,,,,

,②对承台底截面,,,,,,,,,,,,,,,

,制动力的着力点距计算截面,,,,,7.18,m,,,,,,,,,

,弯矩,,,,MT2=,646.2,kN·m,,,,,,,,,

,,,,,,,,,,,,,,,,,

(六)地震水平力计算,,,,,,,,,,,,,,,,

1、地震主动土压力计算(E1地震作用),,,,,,,,,,,,,,,,

,根据《公路桥梁抗震设计细则》(JTG/TB02-01—2008)第5.5.2条,,,,,,,,,,,,,,,

,地震时作用于台背的主动土压力,,,,Eea=,γBH2KA(1+3CiAtanφ/g)/2,,,,,,,,,,

,其中：,,,,,,,,,,,,,,,

,土的重度,,,,γ=,19,kN/m3,,,,,,,,,

,桥台横向宽度,,,,B=,13.000,m,,,,,,,,,

,台背土的内摩擦角,,,,φ=,35°,,,,,,,,,,

,台背的主动土压力系数,,,,,,KA=cos2φ/(1+sinφ)2=,0.2710,,,,,,,,

,抗震重要性系数(E1地震作用),,,,Ci=,0.34,,,,,,,,,,

,水平向设计基本地震动加速度峰值,,,,A=,0.10,g,,,,,,,,,

,①对台身底截面,,,,,,,,,,,,,,,

,计算土层高度,,,,H1=,6.63,m,,,,,,,,,

,主动土压力,,,,Eea1=,1576.2,kN,,,,,,,,,

,作用点距计算土层底面,,,,,Cea1=0.4H1=,2.652,m,,,,,,,,

,弯矩,,,,,Mea1=Eea1Cea1=,4180.0,kN·m,,,,,,,,

,②对承台截面,,,,,,,,,,,,,,,

,计算土层高度,,,,H2=H1=,6.63,m,,,,,,,,,

,主动土压力,,,,Eea2=Eea1=,1576.2,kN,,,,,,,,,

,作用点距计算土层底面,,,,Cea2=Cea1,+1.6=,4.252,m,,,,,,,,

,弯矩,,,,,Mea2=Eea2Cea2=,6701.9,kN·m,,,,,,,,

2、桥台的水平地震力计算(E1地震作用),,,,,,,,,,,,,,,,

,1)水平地震力计算,,,,,,,,,,,,,,,

,根据《公路桥梁抗震设计细则》(JTG/TB02-01—2008)第6.9.1条,,,,,,,,,,,,,,,

,桥台的水平地震力,,,,Ehau=,CiCsCdAGau/g,,,,,,,,,,

,其中：,,,,,,,,,,,,,,,

,水平向设计基本地震动加速度峰值,,,,A=,0.10,g,,,,,,,,,

,抗震重要性系数(E1地震作用),,,,Ci=,0.34,,,,,,,,,,

,场地系数,,,,Cs=,1.0,,,,,,,,,,

,阻尼调整系数,,,,Cd=,1.0,,,,,,,,,,

,①上部结构,,,,,,,,,,,,,,,

,根据《公路桥梁抗震设计细则》第6.9.1条，设有固定支座的梁桥桥台，应计入由上部结构所产生的水平地,,,,,,,,,,,,,,,

震力。,,,,,,,,,,,,,,,,

,一孔上部结构重力,,,,2P1=,7400.0,kN,,,,,,,,,

,水平地震力,,,,Ehau1=,251.6,kN,,,,,,,,,

,对台身底截面偏心距,,,,e1Ⅰ=,5.580,m,,,,,,,,,

,对承台底截面偏心距,,,,e1Ⅱ=,7.180,m,,,,,,,,,

,②桥台背墙,,,,,,,,,,,,,,,

,背墙重力,,,,P2=,162.5+,76.4=,238.9,kN,,,,,,,

,水平地震力,,,,Ehau2=,5.5+,2.6=,8.1,kN,,,,,,,

,对台身底截面偏心距,,,,e2Ⅰ=,6.005,m，,5.850,m,,,,,,,

,对承台底截面偏心距,,,,e2Ⅱ=,7.605,m，,7.450,m,,,,,,,

,③桥台台帽,,,,,,,,,,,,,,,

,背墙重力,,,,P3=,612.6,kN,,,,,,,,,

,水平地震力,,,,Ehau3=,20.8,kN,,,,,,,,,

,对台身底截面偏心距,,,,e3Ⅰ=,4.730,m,,,,,,,,,

,对承台底截面偏心距,,,,e3Ⅱ=,6.330,m,,,,,,,,,

,④桥台台身重,,,,,,,,,,,,,,,

,台身重力,,,,P4=,1060.8,kN,,,,,,,,,

,水平地震力,,,,Ehau4=,36.1,kN,,,,,,,,,

,对台身底截面偏心距,,,,e4Ⅰ=,2.040,m,,,,,,,,,

,对承台底截面偏心距,,,,e4Ⅱ=,3.640,m,,,,,,,,,

,⑤桥头搭板,,,,,,,,,,,,,,,

,搭板力,,,,P5=,273.0,kN,,,,,,,,,

,水平地震力,,,,Ehau5=,9.3,kN,,,,,,,,,

,对台身底截面偏心距,,,,e5Ⅰ=,6.470,m,,,,,,,,,

,对承台底截面偏心距,,,,e5Ⅱ=,8.070,m,,,,,,,,,

,2)地震对各截面所产生的水平力及弯矩,,,,,,,,,,,,,,,

,①对台身底截面,,,,,,,,,,,,,,,

,水平力,,,,,,,EhauⅠ=Ehau1+Ehau2+Ehau3+Ehau4+Ehau5=,325.9,kN,,,,,,

,弯矩,,,,,,,,MhauⅠ=Ehau1e1Ⅰ+Ehau2e2Ⅰ+Ehau3e3Ⅰ+Ehau4e4Ⅰ+Ehau5e5Ⅰ=,1684.5,kN·m,,,,,

,②对承台底截面,,,,,,,,,,,,,,,

,水平力,,,,,,,EhauⅡ=Ehau1+Ehau2+Ehau3+Ehau4+Ehau5=,325.9,kN,,,,,,

,弯矩,,,,,,,,MhauⅡ=Ehau1e1Ⅱ+Ehau2e2Ⅱ+Ehau3e3Ⅱ+Ehau4e4Ⅱ+Ehau5e5Ⅱ=,2205.9,kN·m,,,,,

,,,,,,,,,,,,,,,,,

(七)内力汇总及组合表,,,,,,,,,,,,,,,,

1、对台身底截面,,,,,,,,,,,,,,,,

序号,项目,,,,,,,,台身底截面,,,,,,,

,,,,,,,,,竖向力,水平力,弯矩,,,,,

,,,,,,,,,P(kN),H(kN),M(kN),,,,,

1,永久作用,结构重力,,,,,,,5885.3,,772.8,,,,,

2,,土侧压力,,,,,,,,1336.1,2952.8,,,,,

3,可变作用,汽车荷载,,,,,,,529.2,,142.9,,,,,

4,,汽车冲击力,,,,,,,153.7,,41.5,,,,,

5,,汽车引起的土侧压力,,,,,,,,236.2,783.1,,,,,

6,,汽车制动力/支座摩阻力,,,,,,,,90.0,502.2,,,,,

7,偶然作用,地震土压力,,,,,,,,1576.2,4180.0,,,,,

8,,地震水平荷载,,,,,,,,325.9,1684.5,,P(kN),H(kN),,

承载能力极限状态,基本组合,Ⅰ,γ0[1.2*①+1.4*②+1.4*(③+④)],,,,,,8018.5,1870.6,5319.5,FALSE,8018.5,1870.6,Ⅰ,基本组合

,,Ⅰ',γ0[1.0*①+1.4*②+1.4*(③+④)],,,,,,6841.4,1870.6,5164.9,FALSE,6841.4,1870.6,Ⅰ',基本组合

,,Ⅱ,γ0(1.2*①+1.4*②+1.4*⑤),,,,,,7062.4,2201.3,6157.6,FALSE,7062.4,2201.3,Ⅱ,基本组合

,,Ⅱ',γ0(1.0*①+1.4*②+1.4*⑤),,,,,,5885.3,2201.3,6003.1,FALSE,5885.3,2201.3,Ⅱ',基本组合

,,Ⅲ,γ0[1.2*①+1.4*②+1.4*(③+④)+0.8*1.4*⑤],,,,,,8018.5,2135.1,6196.5,FALSE,8018.5,2135.1,Ⅲ,基本组合

,,Ⅲ',γ0[1.0*①+1.4*②+1.4*(③+④)+0.8*1.4*⑤],,,,,,6841.4,2135.1,6042.0,FALSE,6841.4,2135.1,Ⅲ',基本组合

,,"Ⅲ""",γ0[1.2*①+1.4*②+1.4*⑤+0.8*1.4*(③+④)],,,,,,7827.3,2201.3,6364.2,FALSE,7827.3,2201.3,"Ⅲ""",基本组合

,,"Ⅲ""'",γ0[1.0*①+1.4*②+1.4*⑤+0.8*1.4*(③+④)],,,,,,6650.2,2201.3,6209.6,FALSE,6650.2,2201.3,"Ⅲ""'",基本组合

,,Ⅳ,γ0[1.2*①+1.4*②+1.4*(③+④)+0.7*1.4*(⑤+⑥)],,,,,,8018.5,2190.3,6579.1,FALSE,8018.5,2190.3,Ⅳ,基本组合

,,Ⅳ',γ0[1.0*①+1.4*②+1.4*(③+④)+0.7*1.4*(⑤+⑥)],,,,,,6841.4,2190.3,6424.5,FALSE,6841.4,2190.3,Ⅳ',基本组合

,,"Ⅳ""",γ0[1.2*①+1.4*②+1.4*⑤+0.7*1.4*(③+④+⑥)],,,,,,7731.6,2289.5,6830.5,6830.5,7731.6,2289.5,"Ⅳ""",基本组合

,,"Ⅳ""'",γ0[1.0*①+1.4*②+1.4*⑤+0.7*1.4*(③+④+⑥)],,,,,,6554.6,2289.5,6675.9,FALSE,6554.6,2289.5,"Ⅳ""'",基本组合

,,"Ⅳ""""",γ0[1.2*①+1.4*②+1.4*⑥+0.7*1.4*(③+④+⑤)],,,,,,7731.6,2228.1,6712.5,FALSE,7731.6,2228.1,"Ⅳ""""",基本组合

,,"Ⅳ""""'",γ0[1.0*①+1.4*②+1.4*⑥+0.7*1.4*(③+④+⑤)],,,,,,6554.6,2228.1,6558.0,FALSE,6554.6,2228.1,"Ⅳ""""'",基本组合

,偶然组合,Ⅵ,①+⑧+⑨,,,,,,5885.3,1902.1,6637.3,FALSE,5885.3,1902.1,Ⅵ：地震作用,偶然组合

正常使用极限状态,短期效应组合,Ⅰ,①+②+0.7*③,,,,,,6255.7,1336.1,3825.6,FALSE,6255.7,1336.1,Ⅰ,

,,Ⅱ,①+②+⑤+⑥,,,,,,5885.3,1662.3,5010.9,FALSE,5885.3,1662.3,Ⅱ,

,,Ⅲ,①+②+0.7*③+⑤+⑥,,,,,,6255.7,1662.3,5110.9,5110.9,6255.7,1662.3,Ⅲ,

,长期效应组合,Ⅰ,①+②+0.4*③,,,,,,6097.0,1336.1,3782.8,,,,,

,,Ⅱ,①+②+⑤+⑥,,,,,,5885.3,1662.3,5010.9,,,,,

,,Ⅲ,①+②+0.4*③+⑤+⑥,,,,,,6097.0,1662.3,5068.1,,,,,

2、对承台底截面,,,,,,,,,,,,,,,,

序号,项目,,,,,,,,承台底截面,,,,,,,

,,,,,,,,,竖向力,水平力,弯矩,,,,,

,,,,,,,,,P(kN),H(kN),M(kN),,,,,

1,永久作用,结构重力,,,,,,,7956.0,,44.5,,,,,

2,,土侧压力,,,,,,,,1336.1,5090.6,,,,,

3,可变作用,汽车荷载,,,,,,,529.2,,142.9,,,,,

4,,汽车冲击力,,,,,,,153.7,,41.5,,,,,

5,,汽车引起的土侧压力,,,,,,,,236.2,1161.0,,,,,

6,,汽车制动力/支座摩阻力,,,,,,,,90.0,646.2,,,,,

7,偶然作用,地震土压力,,,,,,,,1576.2,6701.9,,,,,

8,,地震水平荷载,,,,,,,,325.9,2205.9,,P(kN),H(kN),,

承载能力极限状态,基本组合,Ⅰ,γ0[1.2*①+1.4*②+1.4*(③+④)],,,,,,10503.4,1870.6,7438.5,FALSE,10503.4,1870.6,Ⅰ,基本组合

,,Ⅰ',γ0[1.0*①+1.4*②+1.4*(③+④)],,,,,,8912.2,1870.6,7429.6,FALSE,8912.2,1870.6,Ⅰ',基本组合

,,Ⅱ,γ0(1.2*①+1.4*②+1.4*⑤),,,,,,9547.3,2201.3,8805.8,FALSE,9547.3,2201.3,Ⅱ,基本组合

,,Ⅱ',γ0(1.0*①+1.4*②+1.4*⑤),,,,,,7956.0,2201.3,8796.9,FALSE,7956.0,2201.3,Ⅱ',基本组合

,,Ⅲ,γ0[1.2*①+1.4*②+1.4*(③+④)+0.8*1.4*⑤],,,,,,10503.4,2135.1,8738.9,FALSE,10503.4,2135.1,Ⅲ,基本组合

,,Ⅲ',γ0[1.0*①+1.4*②+1.4*(③+④)+0.8*1.4*⑤],,,,,,8912.2,2135.1,8729.9,FALSE,8912.2,2135.1,Ⅲ',基本组合

,,"Ⅲ""",γ0[1.2*①+1.4*②+1.4*⑤+0.8*1.4*(③+④)],,,,,,10312.2,2201.3,9012.3,FALSE,10312.2,2201.3,"Ⅲ""",基本组合

,,"Ⅲ""'",γ0[1.0*①+1.4*②+1.4*⑤+0.8*1.4*(③+④)],,,,,,8720.9,2201.3,9003.4,FALSE,8720.9,2201.3,"Ⅲ""'",基本组合

,,Ⅳ,γ0[1.2*①+1.4*②+1.4*(③+④)+0.7*1.4*(⑤+⑥)],,,,,,10503.4,2190.3,9209.6,FALSE,10503.4,2190.3,Ⅳ,基本组合

,,Ⅳ',γ0[1.0*①+1.4*②+1.4*(③+④)+0.7*1.4*(⑤+⑥)],,,,,,8912.2,2190.3,9200.7,FALSE,8912.2,2190.3,Ⅳ',基本组合

,,"Ⅳ""",γ0[1.2*①+1.4*②+1.4*⑤+0.7*1.4*(③+④+⑥)],,,,,,10216.5,2289.5,9619.8,9619.8,10216.5,2289.5,"Ⅳ""",基本组合

,,"Ⅳ""'",γ0[1.0*①+1.4*②+1.4*⑤+0.7*1.4*(③+④+⑥)],,,,,,8625.3,2289.5,9610.9,FALSE,8625.3,2289.5,"Ⅳ""'",基本组合

,,"Ⅳ""""",γ0[1.2*①+1.4*②+1.4*⑥+0.7*1.4*(③+④+⑤)],,,,,,10216.5,2228.1,9403.5,FALSE,10216.5,2228.1,"Ⅳ""""",基本组合

,,"Ⅳ""""'",γ0[1.0*①+1.4*②+1.4*⑥+0.7*1.4*(③+④+⑤)],,,,,,8625.3,2228.1,9394.6,FALSE,8625.3,2228.1,"Ⅳ""""'",基本组合

,偶然组合,Ⅴ,①+⑧+⑨,,,,,,7956.0,1902.1,8952.4,FALSE,7956.0,1902.1,Ⅴ：地震作用,偶然组合

正常使用极限状态,短期效应组合,Ⅰ,①+②+0.7*③,,,,,,8326.5,1336.1,5235.2,FALSE,8326.5,1336.1,Ⅰ,

,,Ⅱ,①+②+⑤+⑥,,,,,,7956.0,1662.3,6942.4,FALSE,7956.0,1662.3,Ⅱ,

,,Ⅲ,①+②+0.7*③+⑤+⑥,,,,,,8326.5,1662.3,7042.4,7042.4,8326.5,1662.3,Ⅲ,

,长期效应组合,Ⅰ,①+②+0.4*③,,,,,,8167.7,1336.1,5192.3,,,,,

,,Ⅱ,①+②+⑤+⑥,,,,,,7956.0,1662.3,6942.4,,,,,

,,Ⅲ,①+②+0.4*③+⑤+⑥,,,,,,8167.7,1662.3,6999.6,,,,,

,,,,,,,,,,,,,,,,,

(八)台身内力及配筋计算,,,,,,,,,,,,,,,,

1、承载能力极限状态台身内力及配筋计算,,,,,,,,,,,,,,,,

,1)作用于台身底面处最不利组合作用效应,,,,,,,,,,,,,,,

,"作用于台身底面处承载能力极限状态作用效应以基本组合Ⅳ""控制设计。",,,,,,,,,,,,,,,

,轴向力,,,,Nd=,7731.6,kN,,,,,,,,,

,最大弯矩,,,,Md=,6830.5,kN·m,,,,,,,,,

,2)台身配筋计算,,,,,,,,,,,,,,,

,按《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTGD62—2004)第5.3.5条计算,,,,,,,,,,,,,,,

,相对界限受压区高度,,,,ξb=,0.56,,,,,,,,,,

,矩形截面高度,,,,h=,0.80,m,,,,,,,,,

,矩形截面宽度,,,,b=,13.000,m,,,,,,,,,

,截面边缘至纵向钢筋合力点的距离,,,,,a=as'=,0.06,m,,,,,,,,

,构件支点间长度,,,,l=,5.580,m,,,,,,,,,

,构件计算长度系数,,,,,2.0,,,,,,,,,,

,构件的计算长度,,,l0=,2.0×l=,11.160,m,,,,,,,,,

,惯性半径,,,i=,=,0.231,m,,,,,,,,,

,长细比,,,,l0/i=,48.324,>,17.5,,,,,,,,

,∴考虑偏心距增大系数,,,,,,,,,,,,,,,

,偏心矩增大系数,,,,η=,,,,,,,,,,,

,式中：,,,,,,,,,,,,,,,

,轴向力对截面重心轴的偏心距,,,,,e0=Md/Nd=,0.883,m,,,,,,,,

,截面有效高度,,,,h0=h-a=,0.74,m,,,,,,,,,

,荷载偏心率对截面曲率的影响系数,,,,,,ξ1=0.2+2.7e0/h0=,3.423,>,1.0,,,,,,

,∴,,,,ξ1=,1.000,,,,,,,,,,

,构件长细比对截面曲率的影响系数,,,,,,ξ2=1.15-0.01l0/h=,1.011,>,1.0,,,,,,

,∴,,,,ξ2=,1.000,,,,,,,,,,

,∴,,,,η=,1.116,,,,,,,,,,

,,,,,ηe0=,0.986,m,,,,,,,,,

,轴向力至受拉边纵向钢筋合力点的距离,,,,,,e=ηe0+h/2-a=,1.326,m,,,,,,,

,轴向力至受压边纵向钢筋合力点的距离,,,,,,,,,,,,,,,

,台身混凝土轴心抗压强度设计值,,,,fcd=,13.8,MPa,,,,,,,,,

,纵向钢筋的抗拉、抗压强度设计值,,,,,fsd=fsd'=,280,MPa,,,,,,,,

,截面受压区矩形应力图高度与实际受压区高度的比值,,,,,,β=,0.80,,,,,,,,

,矩形截面对称配筋，As=As',,,,,,,,,,,,,,,

,假定为大偏心受压，σs=fsd，则,,,,,,,,,,,,,,,

,,,,,γ0Nd≤,fcdbx,,,,,,,,,,

,∴截面受压区高度,,,,x=,0.043,m,,,,,,,,,

,相对受压区高度,,,,ξ=x/h0=,0.058,≤,ξb=,0.56,,,,,,,

,∴为大偏心受压构件,,,,,,,,,,,,,,,

,,,,,γ0Nde≤,fcdbx(h0-x/2)+fsd'As'(h0-as'),,,,,,,,,,

,∴,,,,,As=As'=,0.0247,m2,,,,,,,,

,矩形截面对称配筋的钢筋混凝土小偏心受压构件，其钢筋截面面积可按下式计算,,,,,,,,,,,,,,,

,,,,As=As'=,,,,,,,,,,,,

,式中相对受压区高度,,,ξ=,,,,=,0.5589,,,,,,,

,∴,,,,As=As'=,-0.1539,m2,,,,,,,,,

,∴最小受拉或受压区纵向钢筋面积,,,,,As=As'=,0.0247,m2,,,,,,,,

,桥台台身纵向主筋直径为,,,φ,25mm,,,,,,,,,,,

,∴持久状况承载能力极限状态计算台身一侧所需最小纵向钢筋根数为,,,,,,,,51,根,,,,,,

2、构造规定,,,,,,,,,,,,,,,,

,根据《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTGD62—2004)第9.1.12条，,,,,,,,,,,,,,,,

,偏心受压构件全部纵向钢筋的配筋百分率不应小于,,,,,,0.5,,,,,,,,,

,桥台台身纵向主筋直径为,,,φ,25mm,,,,,,,,,,,

,∴构造规定台身一侧最小纵向钢筋根数为,,,,,53,根,,,,,,,,,

3、正常使用极限状态台身裂缝宽度验算,,,,,,,,,,,,,,,,

,1)作用台身底面处短期效应组合,,,,,,,,,,,,,,,

,作用台身底面处正常使用极限状态短期效应组合以组合Ⅲ控制设计,,,,,,,,,,,,,,,

,轴向力,,,,Ns=,6255.7,kN,,,,,,,,,

,最大弯矩,,,,Ms=,5110.9,kN·m,,,,,,,,,

,台身正常使用极限状态作用效应以台身底截面(Ⅱ-Ⅱ截面)组合Ⅲ控制设计。,,,,,,,,,,,,,,,

,2)作用作用台身底面处长期效应组合,,,,,,,,,,,,,,,

,作用于台身底面处长期效应组合Ⅲ轴向力为,,,,,,,,,,,,,,,

,,,,,Nl=,6097.0,kN,,,,,,,,,

,3)裂缝宽度验算,,,,,,,,,,,,,,,

,按《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTGD62—2004)第6.4.3、6.4.4条计算,,,,,,,,,,,,,,,

,轴向力Ns的偏心距,,,,e0=Ms/Ns=,0.817,m,,,,,,,,,

,截面高度,,,,h=,0.80,m,,,,,,,,,

,截面有效高度,,,,h0=,0.74,m,,,,,,,,,

,构件的计算长度,,,,l0=,11.160,m,,,,,,,,,

,使用阶段的偏心距增大系数,,,,ηs=,,=,1.0441,,,,,,,,

,,,,,l0/h=,13.950,≤,14,,,,,,,,

,取,,,,ηs=,1.0000,,,,,,,,,,

,截面重心至纵向受拉钢筋合力点的距离,,,,,ys=,0.34,m,,,,,,,,

,轴向压力作用点至纵向受拉钢筋合力点的距离,,,,,,es=ηse0+ys=,0.340,m,,,,,,,

,受压翼缘截面面积与腹板有效截面面积的比值,,,,,γf'=,0,,,,,,,,,

,纵向受拉钢筋合力点至截面受压区合力点的距离,,,,,z=,[0.87-0.12(1-γf')(h0/es)2]h0,,,,,,,,,

,,,,,,=,0.223,≤,0.87h0=,0.644,m,,,,,

,取,,,,z=,0.223,m,,,,,,,,,

,纵向钢筋直径,,,,d=,25,mm,,,,,,,,,

,一侧纵向钢筋设计采用根数,,,,,53,根,,,,,,,,,

,受拉区纵向钢筋截面面积,,,,As=,0.0260,m2,,,,,,,,,

,∴钢筋应力,,,,σss=Ns(es-z)/(Asz)=,125.91,MPa,,,,,,,,,

,纵向受拉钢筋配筋率,,,ρ=As/bh0=,,0.0027,≤,0.02,,,,,,,,

,,,,,,,<,0.006,,,,,,,,

,取,,,,ρ=,0.006,,,,,,,,,,

,钢筋表面形状系数,,,,C1=,1.0,,,,,,,,,,

,作用长期效应影响系数,,,,,C2=1+0.5Nl/Ns=,1.487,,,,,,,,,

,与构件受力性质有关的系数(偏心受压构件),,,,,C3=,0.9,,,,,,,,,

,钢筋的弹性模量,,,,Es=,200000,MPa,,,,,,,,,

,∴最大裂缝宽度,,,,Wfk=,C1C2C3σss(30+d)/[Es(0.28+10ρ)],,,,,,,,,,

,,,,,=,0.136,mm≤,0.20mm,,,,,,,,

,∴满足规范裂缝宽度要求,,,,,,,,,,,,,,,

,,,,,,,,,,,,,,,,,

(九)桩基计算,,,,,,,,,,,,,,,,

1、桩长验算,,,,,,,,,,,,,,,,

,根据《公路桥涵地基与基础设计规范》(JTGD63—2007)第1.0.8条，地基进行竖向承载力验算时，传至承台,,,,,,,,,,,,,,,

底面的作用效应按正常使用极限状态的短期效应组合采用，其中可变作用的频遇值系数均为1.0，且汽车荷载应,,,,,,,,,,,,,,,,

计入冲击系数。,,,,,,,,,,,,,,,,

,以承台底截面(Ⅱ-Ⅱ截面)的短期效应组合(①+③+④)控制桩长设计。,,,,,,,,,,,,,,,

,承台底面以上竖向荷载组合设计值,,,,Pd=,8639.0,kN,,,,,,,,,

,桥台桩基个数,,,,n桩=,4,,,,,,,,,,

,单桩桩顶竖向力,,,,,P0=Pd/n桩=,2159.7,kN,,,,,,,,

,桥台桩径,,,,d=,1.5,m,,,,,,,,,

,桥台桩基础采用嵌岩桩计算,,,,,,,,,,,,,,,

,根据《公路桥涵地基与基础设计规范》第5.3.4条，支承、嵌岩桩的单桩轴向受压承载力容许值为,,,,,,,,,,,,,,,

,,,,,[Ra]=,c1Apfrk+u∑c2ihifrki+0.5ζsu∑liqik,,,,,,,,,,

,式中：,,,,,,,,,,,,,,,

,岩层的端阻发挥系数,,,,c1=,0.3,,,,,,,,,,

,桩端截面面积,,,,Ap=,1.767,m2,,,,,,,,,

,桩端岩石饱和单轴抗压强度标准值,,,,frk=,0,kPa,,,,,,,,,

,∴总端阻力,,,,c1Apfrk=,0.0,kN,,,,,,,,,

,桩身周长,,,,u=,4.712,m,,,,,,,,,

,岩层的侧阻发挥系数,,,,c2=,0.024,,,,,,,,,,

,桩嵌入岩层部分的厚度,,,,h=,5.0,m,,,,,,,,,

,∴嵌岩段总侧阻力,,,,uc2hfrk=,0.0,kN,,,,,,,,,

,覆盖层土的侧阻力发挥系数,,,,ζs=,FALSE,,,,,,,,,,

,,,,,∑liqik=,#DIV/0!,kN,,,,,,,,,

,∴桩周土总侧阻力,,,,0.5ζsu∑liqik=,#DIV/0!,kN,,,,,,,,,

,∴单桩轴向受压承载力容许值,,,,[Ra]=,#DIV/0!,kPa,,,,,,,,,

,,,,,P=P0+桩身自重-置换土重=,2380.6,kPa≤,[Ra]=,#DIV/0!,kPa,,,,,,

,#DIV/0!,,,,,,,,,,,,,,,

2、承载能力极限状态桩基内力及配筋计算,,,,,,,,,,,,,,,,

,1)作用于承台底面处最不利组合作用效应,,,,,,,,,,,,,,,

,"作用于承台底面处承载能力极限状态作用效应以基本组合Ⅳ""控制设计。",,,,,,,,,,,,,,,

,竖向力,,,,P=,10216.5,kN,,,,,,,,,

,水平力,,,,H=,2289.5,kN,,,,,,,,,

,最大弯矩,,,,M=,9619.8,kN·m,,,,,,,,,

,2)单桩顶作用效应,,,,,,,,,,,,,,,

,桥台桩基个数,,,,n桩=,4,,,,,,,,,,

,单桩顶竖向力,,,,P0=P/n桩=,2554.1,kN,,,,,,,,,

,单桩顶水平力,,,,H0=H/n桩=,572.4,kN,,,,,,,,,

,单桩顶弯矩,,,,M0=M/n桩=,2404.9,kN·m,,,,,,,,,

,考虑支撑梁作用，则桩顶水平力,,,,H0=,0.0,kN,,,,,,,,,

,3)桩基最大弯矩计算,,,,,,,,,,,,,,,

,桥台桩径,,,,d=,1.5,m,,,,,,,,,

,桩的计算宽度,,,,b1=0.9(d+1)=,2.25,m≤,2d=,2.4m,,,,,,,

,∴,,,,b1=,2.25,m,,,,,,,,,

,水平向抗力系数的的比例系数,,,,m=,30000,kN/m4,,,,,,,,,

,桩的混凝土抗压弹性模量,,,,Ec=,28000,MPa,,,,,,,,,

,桩的毛截面惯性矩,,,,I=πd4/64=,0.2485,m4,,,,,,,,,

,桩顶抗弯刚度,,,,EI=0.8EcI=,5.57E+06,kN·m2,,,,,,,,,

,桩的变形系数,,,α=,=,0.4138,,,,,,,,,,

,桩长,,,,h=,10,m,,,,,,,,,

,∴,,,,αh=,4.138,m>,2.5m,,,,,,,,

,根据《公路桥涵地基与基础设计规范》附录P第P.0.4条，按表P.0.4计算作用效应及位移。,,,,,,,,,,,,,,,

,影响系数,,,,kh=,0,,,,,,,,,,

,桩顶水平位移,,,,x0=,,,,,,,,,,,

,桩顶转角,,,,φ0=,,,,,,,,,,,

,取αh＝4.0，由《公路桥涵地基与基础设计规范》表P.0.8查得,,,,,,,,,,,,,,,

,,,,,=,2.4007,,,,,,,,,,

,,,,,=,1.5998,,,,,,,,,,

,,,,,=,1.5998,,,,,,,,,,

,,,,,=,1.7322,,,,,,,,,,

,桩顶水平位移,,,,x0=,0.0040,m,,,,,,,,,

,桩顶转角,,,,φ0=,-0.0018,rad,,,,,,,,,

,桩身弯矩,,,,Mz=,,,,,,,,,,,

,A3、B3、C3、D3由《公路桥涵地基与基础设计规范》表P.0.8查得，计算见下表,,,,,,,,,,,,,,,

,,h=αz,A3,B3,C3,D3,z,Mz,,,,,z,,,

,,(m),,,,,(m),(kN·m),,,,,(m),,,

,,0,0.00000,0.00000,1.00000,0.00000,0,2404.9,,,,2404.9,0.000,,,

,,0.1,-0.00017,-0.00001,1.00000,0.10000,0.242,2404.3,,,,FALSE,0.242,,,

,,0.2,-0.00133,-0.00013,0.99999,0.20000,0.483,2400.3,,,,FALSE,0.483,,,

,,0.3,-0.00450,-0.00067,0.99994,0.30000,0.725,2390.3,,,,FALSE,0.725,,,

,,0.4,-0.01067,-0.00213,0.99974,0.39998,0.967,2372.1,,,,FALSE,0.967,,,

,,0.5,-0.02083,-0.00521,0.99922,0.49991,1.208,2344.6,,,,FALSE,1.208,,,

,,0.6,-0.03600,-0.01080,0.99806,0.59974,1.450,2306.8,,,,FALSE,1.450,,,

,,0.7,-0.05716,-0.02001,0.99580,0.69935,1.692,2258.3,,,,FALSE,1.692,,,

,,0.8,-0.08532,-0.03412,0.99181,0.79854,1.934,2199.1,,,,FALSE,1.934,,,

,,0.9,-0.12144,-0.05466,0.98524,0.89705,2.175,2129.9,,,,FALSE,2.175,,,

,,1,-0.16652,-0.08329,0.97501,0.99445,2.417,2051.1,,,,FALSE,2.417,,,

,,1.1,-0.22152,-0.12192,0.95975,1.09016,2.659,1963.8,,,,FALSE,2.659,,,

,,1.2,-0.28737,-0.17260,0.93783,1.18342,2.900,1868.8,,,,FALSE,2.900,,,

,,1.3,-0.36496,-0.23760,0.90727,1.27320,3.142,1767.6,,,,FALSE,3.142,,,

,,1.4,-0.45515,-0.31933,0.86573,1.35821,3.384,1661.2,,,,FALSE,3.384,,,

,,1.5,-0.55870,-0.42039,0.81504,1.43680,3.625,1561.8,,,,FALSE,3.625,,,

,,1.6,-0.67629,-0.54348,0.73859,1.50695,3.867,1438.3,,,,FALSE,3.867,,,

,,1.7,-0.80848,-0.69144,0.64637,1.56621,4.109,1324.3,,,,FALSE,4.109,,,

,,1.8,-0.95564,-0.86715,0.52997,1.61162,4.350,1210.2,,,,FALSE,4.350,,,

,,1.9,-1.11796,-1.07357,0.38503,1.63969,4.592,1097.0,,,,FALSE,4.592,,,

,,2,-1.29535,-1.31361,0.20676,1.64628,4.834,985.8,,,,FALSE,4.834,,,

,,2.2,-1.69334,-1.90567,-0.27087,1.57538,5.317,772.3,,,,FALSE,5.317,,,

,,2.4,-2.14117,-2.66329,-0.94885,1.35201,5.801,574.9,,,,FALSE,5.801,,,

,,2.6,-2.62126,-3.59987,-1.87734,0.91679,6.284,396.4,,,,FALSE,6.284,,,

,,2.8,-3.10341,-4.71748,-3.10791,0.19729,6.767,237.7,,,,FALSE,6.767,,,

,,3,-3.54058,-5.99979,-4.68788,-0.89126,7.251,97.8,,,,FALSE,7.251,,,

,,3.5,-3.91921,-9.54367,-10.34040,-5.85402,8.459,-189.8,,,,FALSE,8.459,,,

,,4,-1.61428,-11.73066,-17.91860,-15.07550,9.668,-436.4,,,,FALSE,9.668,,,

,由上表得知最大弯矩处,,,,z=,0.000,m,,,,,,,,,

,最大弯矩,,,,Md=,2404.9,kN·m,,,,,,,,,

,该处轴力,,,,Nd=,2554.1,kN,,,,,,,,,

,4)桩基配筋计算,,,,,,,,,,,,,,,

,轴向力偏心距,,,,e0=Md/Nd=,0.942,m,,,,,,,,,

,构件计算长度系数,,,,,0.5,,,,,,,,,,

,构件的计算长度,,l0,=0.5,×4/α=,4.834,m,,,,,,,,,

,惯性半径,,,i=,=d/4=,0.375,m,,,,,,,,,

,长细比,,,,l0/i=,12.890,≤,17.5,,,,,,,,

,∴不考虑偏心距增大系数,,,,,,,,,,,,,,,

,偏心矩增大系数,,,,η=,,,,,,,,,,,

,式中：,,,,,,,,,,,,,,,

,圆截面半径,,,,r=,0.75,m,,,,,,,,,

,纵向钢筋所在圆周的半径,,,,rs=,0.675,m,,,,,,,,,

,截面有效高度,,,,h0=r+rs=,1.425,m,,,,,,,,,

,截面高度,,,,h=2r=,1.5,m,,,,,,,,,

,荷载偏心率对截面曲率的影响系数,,,,,,ξ1=0.2+2.7e0/h0=,1.984,>,1.0,,,,,,

,∴,,,,ξ1=,1.000,,,,,,,,,,

,构件长细比对截面曲率的影响系数,,,,,,ξ2=1.15-0.01l0/h=,1.118,>,1.0,,,,,,

,∴,,,,ξ2=,1.000,,,,,,,,,,

,∴,,,,η=,1.000,,,,,,,,,,

,,,,,ηe0=,0.942,m,,,,,,,,,

,由《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTGD62-2004)附录C有,,,,,,,,,,,,,,,

,配筋率,,,,ρ=,,,,,,,,,,,

,桩的混凝土轴心抗压强度设计值,,,,fcd=,11.5,MPa,,,,,,,,,

,普通钢筋的抗压强度设计值,,,,fsd'=,280,MPa,,,,,,,,,

,,,,,g=rs/r=,0.900,,,,,,,,,,

,假定,,,,ξ=,0.27,,,,,,,,,,

,,,,,A=,0.4992,,,,,,,,,,

,,,,,B=,0.3717,,,,,,,,,,

,,,,,C=,-1.1254,,,,,,,,,,

,,,,,D=,1.6584,,,,,,,,,,

,,,,,ρ=,0.0036,,,,,,,,,,

,,,,,Ar2fcd+Cρr2fsd'=,2590.2,kN>,Nd=,2554.1,kN,,,,,,

,,,,,Br3fcd+Dρgr3fsd'=,2438.9,kN>,Ndηe0=,2404.9,kN,,,,,,

,∴最小纵向钢筋面积,,,,As=ρπr2=,0.0064,m2,,,,,,,,,

,桥台桩基纵向主筋直径为,,,φ,25mm,,,,,,,,,,,

,∴持久状况承载能力极限状态计算桩基所需最小纵向钢筋根数为,,,,,,,13,根,,,,,,,

3、构造规定,,,,,,,,,,,,,,,,

,根据《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTGD62—2004)第9.1.12条，,,,,,,,,,,,,,,,

,偏心受压构件全部纵向钢筋的配筋百分率不应小于,,,,,,0.5,,,,,,,,,

,桥台台身纵向主筋直径为,,,φ,25mm,,,,,,,,,,,

,∴构造规定桩基最小纵向钢筋根数为,,,,,19,根,,,,,,,,,

4、正常使用极限状态桩基裂缝宽度验算,,,,,,,,,,,,,,,,

,1)作用短期效应组合,,,,,,,,,,,,,,,

,①作用于承台底面处正常使用极限状态短期效应组合以组合Ⅲ控制设计,,,,,,,,,,,,,,,

,竖向力,,,,P短=,8326.5,kN,,,,,,,,,

,水平力,,,,H短=,1662.3,kN,,,,,,,,,

,最大弯矩,,,,M短=,7042.4,kN·m,,,,,,,,,

,②单桩顶作用短期效应,,,,,,,,,,,,,,,

,桥台桩基个数,,,,n桩=,4,,,,,,,,,,

,单桩顶竖向力,,,,P0短=P短/n桩=,2081.6,kN,,,,,,,,,

,单桩顶水平力,,,,H0短=H短/n桩=,415.6,kN,,,,,,,,,

,单桩顶弯矩,,,,M0短=M短/n桩=,1760.6,kN·m,,,,,,,,,

,考虑支撑梁作用，则桩顶水平力,,,,H0短=,0.0,kN,,,,,,,,,

,③桩基最大弯矩计算,,,,,,,,,,,,,,,

,桩顶水平位移,,,,x0=,0.0030,m,,,,,,,,,

,桩顶转角,,,,φ0=,-0.0013,rad,,,,,,,,,

,桩身弯矩Mz计算见下表,,,,,,,,,,,,,,,

,,h=αz,A3,B3,C3,D3,z,Mz,,,,,z,,,

,,(m),,,,,(m),(kN·m),,,,,(m),,,

,,0,0.00000,0.00000,1.00000,0.00000,0,1760.6,,,,1760.6,0.000,,,

,,0.1,-0.00017,-0.00001,1.00000,0.10000,0.242,1760.2,,,,FALSE,0.242,,,

,,0.2,-0.00133,-0.00013,0.99999,0.20000,0.483,1757.2,,,,FALSE,0.483,,,

,,0.3,-0.00450,-0.00067,0.99994,0.30000,0.725,1749.9,,,,FALSE,0.725,,,

,,0.4,-0.01067,-0.00213,0.99974,0.39998,0.967,1736.6,,,,FALSE,0.967,,,

,,0.5,-0.02083,-0.00521,0.99922,0.49991,1.208,1716.5,,,,FALSE,1.208,,,

,,0.6,-0.03600,-0.01080,0.99806,0.59974,1.450,1688.7,,,,FALSE,1.450,,,

,,0.7,-0.05716,-0.02001,0.99580,0.69935,1.692,1653.2,,,,FALSE,1.692,,,

,,0.8,-0.08532,-0.03412,0.99181,0.79854,1.934,1609.9,,,,FALSE,1.934,,,

,,0.9,-0.12144,-0.05466,0.98524,0.89705,2.175,1559.3,,,,FALSE,2.175,,,

,,1,-0.16652,-0.08329,0.97501,0.99445,2.417,1501.6,,,,FALSE,2.417,,,

,,1.1,-0.22152,-0.12192,0.95975,1.09016,2.659,1437.6,,,,FALSE,2.659,,,

,,1.2,-0.28737,-0.17260,0.93783,1