装配式预应力混凝土T型简支梁桥设计

1、装配式预应力混凝土T型简支梁桥设计第一章设计资料、构造布置、梁毛截面几何特性及计算第一节设计资料1、桥面跨径及桥宽标准跨径：总体方案选择的结果，采用装配式预应力混凝土T型简支梁，跨度25ml主梁长：伸缩缝采用4cm,预制梁长24.96m；计算跨径：取相邻支座中心间距 24.5m；桥面净空：由于该桥所在线路的宽度较大，确定采用分离式桥面；左半幅路面布置：0.5m （护栏）+12m （行车道）+0.8m （护栏+检修道）=13.3m。2、主要技术指标设计荷载：公路I级；结构重要性系数为1.1 ;桥面坡度：行车道单向横坡2%3、材料性能参数（1）混凝土强度等级为C40,主要强度指标为：强度标准值fc

2、k =26.8 MPa, f 我=2.4 MPatk强度设计值fcd =18.4 MPa , ftd =1.65 MPa弹性模量Ec=3.25 X 104 MPaca（2）预应力钢筋采用1X7标准型-15.2-1860- H-GB/T5224-1995钢绞线。其强度指为：抗拉强度标准值fpk =1860MPa抗拉强度设计值fpd =1260MPa弹性模量Ep=1.95 X 105 MPa一 t 之相对界限受压区局度 b =0.4 , pu =0.2563(3)普通钢筋纵向抗拉普通钢筋采用HRB40O!冈筋，其强度指标为抗拉强度标准值fsk=400MPa抗拉强度设计值fsd=330MPa一一一

3、一_一一 E上相对界限受压区局度 b=0.53pu =0.1985箍筋及构造钢筋采用HRB335其强度指标为抗拉强度标准值fsk=335MPa抗拉强度设计值fsd=280MPa弹性模量Es=2.0义105 MPa4、设计依据1)公路桥涵设计通用规范(JTG D60- 2004),简称桥规；2)公路钢筋混凝土及预应力混凝土桥涵设计规范(JTG D60-2004),简称公预规；3)公路桥涵地基与基础设计规范(JTG D63-2007);第二节构造布置1、梁间距：采用装配式施工。主梁间距一般在1.82.3之间，本设计选用1.9m,整个横桥向共14片主梁。设计主梁宽均为1.9m。预制时主梁宽为1.6m

4、。主梁之间留有0.3m的后浇带。l l2、主梁高：根据预应力混凝土 T型梁的截面尺寸设计经验，梁高选取在 14 25之间，本设计取较小值，选用1.6m。3、横隔梁间距：为了增强主梁之间的横向连接刚度，处除设置端横隔梁外，还设置了4片中横隔梁，间距为3X5m,共计6片。高取梁高的0.70.9倍，厚度一般取1518cm4、梁肋：根据抗剪强度需要和施工振捣的需要(一般取在1525cm之间),厚度暂定为18cm,在梁端的一个横隔板间距内腹板中部按直线加厚至马蹄宽40cmi5、桥面铺装：10厘米厚40号钢纤维混凝土 +防水层+7厘米厚沥青混凝土(路面一致)。6、桥梁横断面：具体尺寸见图1-1。-96 -

5、ir：j图1-1 主梁横断面（跨中）布置图（单位 cm）7、主梁纵断面布置：见图1 2布置图（单位cnj）图1-2 主梁纵断面第三节截面的几何特性1、预制时翼板宽度为1.6m,使用时为1.9m,二者的截面特性如下;预制跨中横图1-5成桥阶段支点横截面图1-6成桥阶段支点横截面预制跨中横截面：面积：6228.9444周长：650.5162边界框：X: -80.0000 - 80.0000Y:-105.0908 - 54.9092质心：X: 0.0000Y: 0.0000惯性矩：X: 18527369.8464Y: 6171115.3888惯性积：XY: 0.0000旋转半径： X: 54.538

6、1Y: 31.4756主力矩与质心的X-Y方向：I: 6171115.3888J: 18527369.8464成桥阶段跨中横截面：面积：6678.9444周长：710.5162边界框：X: -95.0000 - 95.0000Y:-108.2851 - 51.7149质心：X: 0.0000Y: 0.0000惯性矩：X: 19479095.7115Y: 9624865.3888惯性积：XY: 0.0000旋转半径： X: 54.0046Y: 37.9615主力矩与质心的X-Y方向：I: 9624865.3888J: 19479095.7115预制支点横截面：面积：8664.2824周长：622

7、.5712边界框：X: -80.0000 - 80.0000Y: -98.4036 - 61.5964质心：X: 0.0000Y: 0.0000惯性矩：X: 22021233.8445Y: 6718236.9215惯性积：XY: 0.0000旋转半径： X: 50.4144Y: 27.8459主力矩与质心的X-Y方向：I: 6718236.9215J: 22021233.8444成桥阶段支点横截面：面积：9106.3380周长：685.7490边界框：X: -95.0000 - 95.0000沿0.0000 -1.0000沿1.0000 0.0000沿0.0000 -1.0000沿1.0000

8、 0.0000沿0.0000 1.0000沿-1.0000 0.0000Y: -101.0436 - 58.9564质心:X: 0.0000Y: 0.0000惯性矩：X: 23271527.6099Y: 10168491.7840惯性积：XY: 0.0000旋转半径： X: 50.5523Y: 33.4161主力矩与质心的X-Y方向：I: 10168491.7840J: 23271527.60992、检验截面效率指标p沿0.0000 -1.0000沿1.0000 0.0000以跨中截面为例Im 18527369.8464上核心矩： K= =54.17三A yx6228.9444 54.9092

9、下核心矩:“ I 18527369.8464Kx=28.3SAys 6228.9444105.0908截面效率指标：p= 542=0.52 )0.5 h160根据设计经验，预应力混凝土 T型梁在设计时，检验截面效率指标 p =0.45-0.55 较经济，上述计算表明，初拟主梁跨中截面时合理的。,且较大者亦第二章上部结构设计第一节主梁内力计算(一)包载内力计算1.主梁预制时的自重(第一期横载)g1(1)安跨中截面计算，主梁每延米自重(即先按等截面计算)g 1=0.62289444 X 26=16.195kN/m(2)由马蹄增高和腹板加宽所增加的重量折算成每延米自重1,g2=- (0.866428

10、28-0.6228944) 26=3.166 kN/m(3)横隔梁折算成横向每米自重g3=0.18*1.25*26/5=1.17 kN/m2.桥面板间接头(第二期横载)g4g4=0.3 X 0.15 X 26+0.3 X 0.18 X 6X 26/24.96=1.183kN/m3.栏杆、桥面铺装（第三期横载）g5桥面坡度以盖梁做成斜面找平，桥面铺装为10厘米厚40号钢纤维混凝土 +防水层+7厘米厚沥 青混凝土。钢纤维混凝土的重力密度取为 26kN/m3;沥青混凝土的重力密度取为23kN/m3;每侧的钢筋混凝土护栏重为：7.5KN/m金属制护栏为：5KN/m；沥青混凝土： 0.07 X 2.2=

11、0.154 kN/m ;混凝土垫层（平均厚）：0.1 X 2.2=0.22 kN/m ;故：g5=0.22+0.154+ 5 7.5 =2.457 kN/m6表21各梁的恒载汇总表（单位：KN/m梁号ftl- 第一期荷载Mg gfJp(kN *m.>第三期荷载Qg =gOQ(kN ) 总和(KN/m1(7)19.9460.59152.45722.99452 (6)20.5131.1832.45724.1533 (4) (5)20.5131.1832.45724.153L/2L/4L/8L/4L/8支点2a2以75.0356.2732.83L26.1259.18812.25第一期包 载1

12、(/7) 号主梁1496.5481122.361654.827122.169183.264244.3392 (/6 )号主梁1539.091154.267673.442125.642188.473251.2843 (/4/5)号主梁1539.091154.267673.442125.642188.473251.284第二期包 载1 (/7) 号主梁44.3833.28419.4193.6235.4357.2462 (/6 )号主梁88.7666.56738.8387.24610.86914.4923 (/4/5)号主梁88.7666.56738.8387.24610.86914.492第二期包

13、 载1 (/7) 号主梁184.3487138.255480.66315.0491322.57530.098252 (/6 )号主梁184.3487138.255480.66315.0491322.57530.0982533 (/4/5)号主梁184.3487138.255480.66315.0491322.57530.09825表22包载内力计算结果表（二）活载内力计算1.计算汽车荷载的冲击系数根据公桥规第4.3.2条规定:工 3.14f = 22 24.5(23.25 1(1° 0.19479 厂CCCCC 5 CCC= 5.12Hz26000 0.6239.81=0.1767l

14、nf -0.0157 = 0.27293故：1-1.2732、主梁荷载横向分布系数的计算1）跨中的横向分布系数mc主梁问在翼缘板及横隔梁处采用湿接，且桥宽跨比为 26/25=1.04 >0.5 ,所以本桥并非窄桥, 不宜用偏心压力法计算m。故跨中的横向分布系数m计算方法采用比拟正交异性板法（用查表法计 算）。2）计算几何特性主梁抗弯惯矩I xI x=18527369.8464cmi=18.53 X 106 cm4主梁的比拟单宽抗弯惯矩Jx:Jx3 =18527369.8464cm4/190cm=97512.47cm/cm b横隔梁抗弯惯矩"irr其截面几何特性：面积：14768

15、.0000周长：1302.0000边界框：X: -250.0000 - 250.0000Y:-126.9051 - 24.0949质心：X: 0.0000Y: 0.0000惯性矩：X: 14594325.5678Y: 260477902.6667惯性积：XY: 0.0000旋转半径： X: 31.4363Y: 132.8081主力矩与质心的X-Y方向：I: 14594325.5678沿1.0000 0.0000J: 260477902.6667沿0.0000 1.0000故单位抗弯及抗扭惯矩:,1y 14.591064,、J = =76789.47Cm4/cm)y b 190主梁和横隔梁的抗扭

16、惯矩对于T梁间刚性连接的情况，应按下列公式计算:JTx+JTa= h1 + I Tx+ITy对于主梁梁肋:t 18、诏=0.159, C 1=0.300t228.7b2 - 70"= 0.718 ,C2 =0.186I tx=£ Ci bi ti3 =0.300 X 113X 183+0.186 X40X 28.73=373585.6783cm4对于横隔梁肋:t_18b -150-25=0.144,C=0.303I Ty=0.303 X 125X 183=220712.04cm4jTx+jTa= h1 + I Tx+ I Ty=- X 18 +373585.67833 b

17、a 3190220712.04+500=4351.66 cm4/cm3）计算各梁荷载横向分布系数主梁的荷载横向分布系数m c （比拟正交异性板法）。 比拟正交异性板法N=7DX=0.05L=24.5LB=1.9RB=0XB=12（ 3 Lane）Jx=0.09751247Jy=0.07678947Jtx+Jty=0.004135Coordinates of beam locationNo.y1 -5.72 -3.83 -1.94 05 1.96 3.87 5.7 比拟正交异性板法Coordinates of load latrel influence lineNo. Y beam 1 beam

18、 2 beam 3 beam 4 beam 5 beam 6 beam 71-6.650.49010.35610.24330.13660.0323-0.0717-0.18662-6.60.48740.35450.24260.13670.0331-0.0701-0.18423-6.550.48470.35290.24190.13680.034-0.0685-0.18184-6.50.4820.35130.24120.13690.0349-0.0669-0.17935-6.450.47930.34970.24050.1370.0357-0.0653-0.17696-6.40.47650.34810

19、.23980.13710.0366-0.0637-0.17457-6.350.47380.34650.23910.13720.0375-0.0621-0.1728-6.30.47110.34490.23840.13730.0383-0.0605-0.16969-6.250.46840.34330.23770.13740.0392-0.0589-0.167210-6.20.46570.34180.2370.13750.0401-0.0573-0.164711-6.150.4630.34020.23630.13760.0409-0.0557-0.162312-6.10.46030.33860.23

20、560.13780.0418-0.0541-0.159913-6.050.45760.3370.23490.13790.0427-0.0524-0.157414-6.0.45480.33540.23420.1380.0435-0.0508-0.15515-5.950.45210.33380.23350.13810.0444-0.0492-0.152616-5.90.44940.33220.23280.13820.0452-0.0476-0.150217-5.850.44670.33060.23210.13830.0461-0.046-0.147718-5.80.4440.3290.23140.

21、13840.047-0.0444-0.145319-5.750.44130.32740.23070.13850.0478-0.0428-0.142920-5.70.43860.32580.22990.13860.0487-0.0412-0.140421-5.650.43590.32420.22920.13870.0496-0.0396-0.13822-5.60.43320.32260.22850.13880.0504-0.038-0.135623-5.550.43050.3210.22780.13890.0513-0.0364-0.133124-5.50.42780.31940.22710.1

22、390.0522-0.0348-0.130725-5.450.42510.31780.22640.13910.053-0.0332-0.128326-5.40.42240.31620.22570.13920.0539-0.0316-0.125827-5.350.41970.31460.2250.13930.0548-0.03-0.123428-5.30.4170.3130.22430.13940.0556-0.0284-0.12129-5.250.41430.31140.22360.13950.0565-0.0267-0.118630-5.20.41160.30980.22290.13960.

23、0573-0.0251-0.116131-5.150.40890.30820.22220.13970.0582-0.0235-0.113732-5.10.40630.30660.22150.13980.0591-0.0219-0.111333-5.050.40360.3050.22080.13990.0599-0.0203-0.108834-5.0.40090.30340.22010.140.0608-0.0187-0.106435-4.950.39820.30180.21930.14010.0616-0.0171-0.10436-4.90.39550.30020.21860.14020.06

24、25-0.0155-0.101537-4.850.39280.29860.21790.14030.0634-0.0139-0.099138-4.80.39010.2970.21720.14040.0642-0.0123-0.096739-4.750.38740.29540.21650.14050.0651-0.0107-0.094240-4.70.38480.29380.21580.14060.066-0.0091-0.091841-4.650.38210.29210.21510.14070.0668-0.0075-0.089442-4.60.37940.29050.21440.14080.0

25、677-0.0059-0.086943-4.550.37670.28890.21370.14090.0685-0.0043-0.084544-4.50.37410.28730.21290.1410.0694-0.0027-0.082145-4.450.37140.28570.21220.14110.0702-0.0011-0.079646-4.40.36870.28410.21150.14120.07110.0005-0.077247-4.350.3660.28250.21080.14130.0720.0021-0.074848-4.30.36340.28090.21010.14140.072

26、80.0038-0.072349-4.250.36070.27930.20940.14150.07370.0054-0.069950-4.20.3580.27770.20860.14160.07450.007-0.067551-4.150.35540.27610.20790.14170.07540.0086-0.06552-4.10.35270.27450.20720.14180.07630.0102-0.062653-4.050.350.27290.20650.14190.07710.0118-0.060154-4.0.34740.27130.20580.14190.0780.0134-0.

27、057755-3.950.34470.26970.2050.1420.07880.015-0.055356-3.90.3420.26810.20430.14210.07970.0166-0.052857-3.850.33940.26650.20360.14220.08050.0182-0.050458-3.80.33670.26490.20290.14230.08140.0198-0.04859-3.750.33410.26320.20220.14240.08220.0214-0.045560-3.70.33140.26160.20140.14250.08310.023-0.043161-3.

28、650.32880.260.20070.14260.08390.0246-0.040662-3.60.32610.25840.20.14260.08480.0262-0.038263-3.550.32350.25680.19930.14270.08570.0278-0.035864-3.50.32080.25520.19850.14280.08650.0294-0.033365-3.450.31820.25360.19780.14290.08740.031-0.030966-3.40.31550.2520.19710.1430.08820.0326-0.028467-3.350.31290.2

29、5040.19630.14310.08910.0343-0.02668-3.30.31030.24880.19560.14310.08990.0359-0.023569-3.250.30760.24710.19490.14320.09080.0375-0.021170-3.20.3050.24550.19410.14330.09160.0391-0.018671-3.150.30230.24390.19340.14340.09250.0407-0.016272-3.10.29970.24230.19270.14350.09330.0423-0.013773-3.050.29710.24070.

30、19190.14350.09420.0439-0.011374-3.0.29450.23910.19120.14360.0950.0455-0.008975-2.950.29180.23750.19050.14370.09590.0471-0.006476-2.90.28920.23590.18970.14380.09670.0487-0.00477-2.850.28660.23420.1890.14380.09750.0503-0.001578-2.80.28390.23260.18820.14390.09840.05190.00179-2.750.28130.2310.18750.1440

31、.09920.05350.003480-2.70.27870.22940.18670.14410.10010.05510.005981-2.650.27610.22780.1860.14410.10090.05670.008382-2.60.27350.22620.18530.14420.10180.05830.010883-2.550.27090.22460.18450.14430.10260.060.013284-2.50.26820.22290.18380.14430.10350.06160.015785-2.450.26560.22130.1830.14440.10430.06320.

32、018186-2.40.2630.21970.18230.14450.10520.06480.020687-2.350.26040.21810.18150.14450.1060.06640.023188-2.30.25780.21650.18080.14460.10680.0680.025589-2.250.25520.21490.180.14470.10770.06960.02890-2.20.25260.21320.17920.14470.10850.07120.030491-2.150.250.21160.17850.14480.10940.07280.032992-2.10.24740

33、.210.17770.14480.11020.07440.035493-2.050.24480.20840.1770.14490.1110.0760.037894-2.0.24220.20680.17620.1450.11190.07760.040395-1.950.23960.20520.17550.1450.11270.07920.042896-1.90.2370.20350.17470.14510.11350.08090.045297-1.850.23450.20190.17390.14510.11440.08250.047798-1.80.23190.20030.17320.14520

34、.11520.08410.050299-1.750.22930.19870.17240.14520.11610.08570.0526100-1.70.22670.19710.17160.14530.11690.08730.0551101-1.650.22410.19550.17090.14530.11770.08890.0576102-1.60.22150.19380.17010.14540.11860.09050.0601103-1.550.2190.19220.16930.14540.11940.09210.0625104-1.50.21640.19060.16850.14550.1202

35、0.09370.065105-1.450.21380.1890.16780.14550.12110.09530.0675106-1.40.21130.18740.1670.14560.12190.0970.07107-1.350.20870.18580.16620.14560.12270.09860.0725108-1.30.20610.18410.16540.14560.12350.10020.0749109-1.250.20360.18250.16470.14570.12440.10180.0774110-1.20.2010.18090.16390.14570.12520.10340.07

36、99111-1.150.19840.17930.16310.14570.1260.1050.0824112-1.10.19590.17770.16230.14580.12690.10660.0849113-1.050.19330.1760.16150.14580.12770.10820.0874114-1.0.19080.17440.16080.14580.12850.10980.0899115-0.950.18820.17280.160.14590.12930.11140.0924116-0.90.18560.17120.15920.14590.13020.11310.0949117-0.8

37、50.18310.16960.15840.14590.1310.11470.0974118-0.80.18050.1680.15760.14590.13180.11630.0998119-0.750.1780.16630.15680.1460.13260.11790.1023120-0.70.17540.16470.1560.1460.13340.11950.1048121-0.650.17290.16310.15520.1460.13430.12110.1073122-0.60.17040.16150.15440.1460.13510.12270.1098123-0.550.16780.15

38、990.15360.14610.13590.12430.1124124-0.50.16530.15830.15290.14610.13670.1260.1149125-0.450.16270.15660.15210.14610.13750.12760.1174126-0.40.16020.1550.15130.14610.13830.12920.1199127-0.350.15770.15340.15050.14610.13920.13080.1224128-0.30.15510.15180.14970.14610.140.13240.1249129-0.250.15260.15020.148

39、90.14610.14080.1340.1274130-0.20.15010.14860.14810.14610.14160.13560.1299131-0.150.14760.1470.14730.14610.14240.13730.1324132-0.10.1450.14530.14640.14610.14320.13890.1349133-0.050.14250.14370.14560.14610.1440.14050.13751340.0.140.14210.14480.14610.14480.14210.141350.050.13750.14050.1440.14610.14560.

40、14370.14251360.10.13490.13890.14320.14610.14640.14530.1451370.150.13240.13730.14240.14610.14730.1470.14761380.20.12990.13560.14160.14610.14810.14860.15011390.250.12740.1340.14080.14610.14890.15020.15261400.30.12490.13240.140.14610.14970.15180.15511410.350.12240.13080.13920.14610.15050.15340.15771420

41、.40.11990.12920.13830.14610.15130.1550.16021430.450.11740.12760.13750.14610.15210.15660.16271440.50.11490.1260.13670.14610.15290.15830.16531450.550.11240.12430.13590.14610.15360.15990.16781460.60.10980.12270.13510.1460.15440.16150.17041470.650.10730.12110.13430.1460.15520.16310.17291480.70.10480.119

42、50.13340.1460.1560.16470.17541490.750.10230.11790.13260.1460.15680.16630.1781500.80.09980.11630.13180.14590.15760.1680.18051510.850.09740.11470.1310.14590.15840.16960.18311520.90.09490.11310.13020.14590.15920.17120.18561530.950.09240.11140.12930.14590.160.17280.18821541.0.08990.10980.12850.14580.16080.17440.19081551.050.08740.10820.12770.14580.16150.1760.19331561.10.08490.10660.12690.14580.16230.17770.19591571.150.08240.1050.1260.14570.16310.17930.19841581.20.07990.10340.12520.14570.16390.18090.2011591.250.07740.10180.12440.14570.16470.18250.20361601.30.07490.10020.12350.14560.16540.18410