变截面箱型连续梁桥--桥梁工程毕业设计(共94页).doc

精选优质文档-倾情为你奉上目录专心-专注-专业第一章 方案比选1.1方案选取及尺寸拟定鉴于毛利冲地质地形情况，该处地势崎岖，桥全长较长，故比选方案主要采用预应力混凝土连续梁和斜拉桥形式。根据安全、适用、经济、美观的设计原则，初步拟定了三个方案。1.11方案一：50+80+50m的变截面箱型连续梁桥本桥上部构造为50+80+50m的变截面预应力砼连续梁，箱梁采用的单箱单室截面，箱梁支点截面梁高5m，跨中截面梁高2.5m,梁宽9m，下部构造桥墩为薄壁式桥墩或双柱式墩配桩基础；桥台为重力式U型桥台配扩大基础。由于该桥桥位较高 ，为了减少墩台数量且跨径选择合理。图2 变截面连续梁桥立面图3 变截面连续梁剖面图1.12方案二：4×45m等截面预应力砼连续刚构梁 1.本桥上部构造为4×45m预应力砼连续梁，箱梁采用的单箱单室截面，梁高3m,桥面宽9m, 下部构造桥墩为薄壁式桥墩或双柱式墩配桩基础；桥台为重力式U型桥台配扩大基础。图4 等截面连续梁立面 1.13方案三：65+115m斜拉桥 本桥上部构造为65+115m的箱型截面的斜拉桥，由于斜拉桥的多点支撑故可以大大减少主梁的高度，索距为6m，塔高38m。箱梁采用单相单室，梁高1.8m,梁宽9m，下部构造桥墩为薄壁式桥墩或双柱式墩配桩基础；桥台为重力式U型桥台配扩大基础。 图5 斜拉桥立面图 1.2各方案主要优缺点比较表表2方案一方案二方案三适用性跨越能力较大结构刚度大、变形小、行车平顺舒适、伸缩缝少、抗震能力强跨越能力较大结构刚度大、变形小、行车平顺舒适、伸缩缝少、抗震能力强梁的高跨比小自重明显比其他小，变形小，行车舒适安全性箱梁断面刚度大，施工安全。大跨度连续梁恒载内力占的比重较大，选用变高度梁可以大大减小跨中区段恒载产生的内力。变高度符合梁的内力分布规律。采用悬臂施工时，变高度梁又与施工时的内力状态相吻合。箱梁断面刚度大，施工安全。主桥采用悬臂施工，需要挂篮，吊装设备及。连续梁施工控制复杂，工期较长，连续梁桥主墩需要大型橡胶支座，养护更换麻烦箱梁断面刚度大，施工安全。主桥采用悬臂施工，需要挂篮，吊装设备要求高 由于跨径大，施工难度大工期长墩台少，下部结构施工少经济性变截面连续梁部分上部结构造价较高，支座养护费用较高，上部结构造价相对其他两种较低，主桥的运营养护成本在后期较低。上部结构下部结构由于技术要求高所以造价也高美观性从美学观点出发，变高度梁比较有韵律感，特别是位于城市中的桥梁。整体外形单一，跨径安排较合理，由于桥型较长，主梁结构单一显得有点单调气势宏伟，符合地形特点，但跨径安排较大。显得不协调1.3. 结论通过对比，从受力合理，安全适用，经济美观的角度综合考虑，方案一为最佳推荐方案，即50+80+50m的变截面箱型连续梁桥。第二章 毛截面几何特性计算2.1 基本资料2.1.1 主要技术指标桥型布置：50m+80m+50m变截面连续梁桥（图2-1）桥面净空：净-8m设计荷载：公路I级桥面纵坡：0 %桥面横坡：2%图2-1 主梁横截面图及桥面布置图（单位：cm）2.1.2 材料规格主梁：C50号混凝土，容重为27kN/m3，弹性模量取3.45×107 kPa；桥面铺装：采用防水混凝土，厚度为10cm，容重为25kN/m3；人行道、栏杆：C20号混凝土，容重为25kN/m3；横隔板：C50号混凝土，容重为27kN/m3，弹性模量取3.45×107 kPa。2.2 结构计算简图全桥三跨共取52个单元，53个结点，其中13、12-19、34-41、50-52号单元长为3m，9-11、20-22、31-33、42-44号单元长为4m，6-8、23-25、28-30、45-47号单元长5m，4、5、26、27、48、49号单元长1m。桥墩简化为活动和固定铰支座。结点x、y坐标按各结点对应截面的形心点的位置来确定，结构计算简图，如图2-2所示。图2-2 结构计算简图2.3 毛截面几何特性计算用三角形分块法（GEO2程序）计算主梁截面几何特性，截面编号和坐标系取用，见图2-3。图2-3 截面几何特性计算的三角形分块结点编号图输入数据文件D2-1-1.DAT，内容为：281,-5.0,0.02,5.0,0.03,3.0,0.854,1.6,0.855,0.4,1.256,0.4,3.87,1.6,4.28,3.0,4.29,4.2,3.810,4.2,1.2511,3.0,0.8512,5.0,0.013,5.0,4.114,8.0,4.315,8.0,4.516,-8.0,4.517,-8.0,4.318,-5.0,4.119,-5.0,0.020,-3.0,0.8521,-4.2,1.2522,-4.2,3.823,-3.0,4.224,-1.6,4.225,-0.4,3.826,-0.4,1.2527,-1.6,0.8528,-3.0,0.85以上数据仅为一个结点截面的数据文件，其余结点截面的数据文件省略，其形式与上类同。计算结果，见“表2-1 结点截面几何特性总表”。结点截面几何特性和单元几何特性，分别见表2-2和表2-3。表2-1 结点截面几何特性总表序号节点号截面高度截面面积截面抗弯惯距截面形心位置Hx（m）112.56.465.912741.41222.56.465.912741.41332.56.465.912741.41442.56.465.912741.41552.56.465.912741.41662.526.487856.011121.42772.646.74936.877851.47882.837.173878.39621.56993.17.7844710.80161.6710103.368.4396213.60471.7811113.679.2444617.46011.9112124.0310.237922.71432.0713134.3311.124827.87222.214144.6512.140134.32222.3415155.013.342.41422.4916165.013.342.41422.4917175.013.342.41422.4918184.6512.140134.32222.3419194.3311.124827.87222.220204.0310.237922.71432.0721213.679.2444617.46011.9122223.368.4396213.60471.7823233.17.7844710.80161.6724242.837.173878.39621.5625252.646.74936.877851.4726262.526.487856.011121.4227272.56.465.912741.4128282.526.487856.011121.4229292.646.74936.877851.4730302.837.173878.39621.5631313.17.7844710.80161.6732323.368.4396213.60471.7833333.679.2444617.46011.9134344.0310.237922.71432.0735354.3311.124827.87222.236364.6512.140134.32222.3437375.013.342.41422.4938385.013.342.41422.4939395.013.342.41422.4940404.6512.140134.32222.3441414.3311.124827.87222.242424.0310.237922.71432.0743433.679.2444617.46011.9144443.368.4396213.60471.7845453.17.7844710.80161.6746462.837.173878.39621.5647472.646.74936.877851.4748482.526.487856.011121.4249492.56.465.912741.4150502.56.465.912741.4151512.56.465.912741.4152522.56.465.912741.41表2-2 结点截面几何特性表 序列号节点号截面高度截面面积截面抗弯惯距截面形心位置Hx（m）11-4 50-522.56.465.912741.4126 26 28 482.526.487856.011121.4237 25 29 472.646.74936.877851.4748 24 30 462.837.173878.39621.5659 23 31 453.17.7844710.80161.67610 22 32 443.368.4396213.60471.78711 21 33 453.679.2444617.46011.91812 20 34 424.0310.237922.71432.07913 19 35 414.3311.124827.87222.21014 18 36 404.6512.140134.32222.341115-17 37-395.013.342.41422.49表2-3 单元几何特性表序号单元号截面面积截面抗弯惯距截面形心位置Hx（m）11-4 49-526.465.912741.4125 48 26 276.5.961931.41536 25 28 476.6.1.44547 24 29 466.7.1.51558 23 30 457.479179.59891.61569 22 31 448.12.203151.725710 21 32 438.8420415.53241.845811 20 33 429.7411820.08721.99912 19 34 4110.6813525.293252.1351013 18 35 4011.6324531.09722.271114 17 36 3912.7200538.36822.4151215 16 37 3813.342.41422.49第三章 内力计算及组合3.1 荷载3.1.1 结构重力荷载（1）桥面系荷载防撞护栏重：q1 =（0.3+0.5）×0.2/2+0.2×0.5+0.8×0.2 ×25×2=24.5 kN/m桥面铺装重：q2 =（0.6+0.15）×4/2×25×2 = 21kN/m合计：q = q1+q2 = 45.5 kN/m 将桥面系荷载作为二期恒载以均布荷载的形式加在主梁上。（2）主梁自重按=27kN/m3的容重，以计主梁自重的形式计入恒载中。且在每跨l/4截面、l/2截面以及支点截面各设一道横隔梁，其重量按非结点荷载计算。中跨跨中截面横隔板重：(5-0.4×2)×(2.5-0.25-0.4)-0.8×0.3×2-0.3×0.3×2-1×1.5-0.5××0.75×0.75+0.3×0.3×2 ×0.2×27= 26.497 kN中跨l/4截面横隔板重：(5-0.538×2)×(3.362-0.25-0.538)-0.8×0.3×2-0.3×0.3×2-1.25×1.5-0.5××0.75×0.75+0.3×0.3×2×0.4×27 ×0.4×27= 74.112 kN中跨支点截面横隔板重：(5-0.8×2)×(8-0.25-0.8)-0.8×0.3×2-0.3×0.3×2-1.25×1.5-0.5××0.75×0.75+0.3×0.3×2×0.4×27 ×0.6×27 =165.184 kN边跨l/4截面（靠中跨侧）横隔板重：(5-0.644×2)×(4.029-0.25-0.644)-0.8×0.3×2-0.3×0.3×2-1.25×1.5-0.5××0.75×0.75+0.3×0.3×2×0.4×27 ×0.4×27 = 90.705 kN边跨跨中截面横隔板重：(5-0.495×2)×(3098-0.25-0.495)-0.8×0.3×2-0.3×0.3×2-1.25×1.5-0.5××0.75×0.75+0.3×0.3×2×0.4×27 ×0.4×27 = 66.932 kN边跨l/4截面（靠桥台侧）横隔板重：(5-0.405×2)×(2.51-0.25-0.405)-0.8×0.3×2-0.3×0.3×2-1×1.5-0.5××0.75×0.75+0.3×0.3×2 ×0.2×27= 26.510 kN边跨边支点截面横隔板重：(5-0.4×2)×(2.5-0.25-0.4)-0.8×0.3×2-0.3×0.3×2-1×1.5-0.5××0.75×0.75+0.3×0.3×2 ×0.4×27= 52.984 kN3.1.2 支座不均匀沉降支座不均匀沉降应根据各墩位处地质情况以及基础的布置形式和支座反力大小按基础工程以及有关规范的规定来计算，这里假定中间两桥墩相对两边桥台下沉20mm。在荷载组合中，此项荷载作为SQ2，SQ2中还可包括温度等荷载效应，应根据设计要求来取用。3.1.3 活载汽车： 公路I级车道荷载（由均布荷载qk和集中荷载Pk组成），qk=10.5kN/m，Pk=360kN；计算剪力效应时，Pk=432kN。3.2 结构重力作用以及影响线计算采用FR2程序计算，关心结点取结点153；关心截面取全结构的相关截面。3.2.1 输入数据52,53,5,32,1,0,1,1,53,1 （NM,NJ,NS,NGE,NME,NKA,NCA,NTI,NFI,NFY）1, 1, 2, 1, 12, 2, 3, 1, 23, 3, 4, 1, 3 （中间数据省略，其形式与上类同）50, 50, 51, 1, 351, 51, 52, 1, 252, 52, 53, 1, 1 ISE(I,J),J=1,2 ,(IMG(I,J),J=1,2),I=1,NM1, 0.0 ,0.02, 3.0 , 0.0 3, 6.0 , 0.0 （中间数据省略，其形式与上类同）50, 171, 0.051, 174 , 0.052, 177 ,0.0 ( I,(XY(I,J),J=1,2) )1,27.0,3.45E7 ( I,(WE(I,J),J=1,2),I=1,NME )1, 22.3875 , 61.3615 2, 20.6140 , 58.7755 3, 18.7830 , 55.5940 （中间数据省略，其形式与上类同）30, 32.5510 , 328.0000 31, 33.9680 , 355.9750 32, 34.0600 , 356.4700 (I,(AI(I,J),J=1,2),I=1,NGE)41,9999,0.0,999916,0.0,0.0,999938,9999,0.0,999952,9999,0.0,9999 ( ISJ (SXYM(J),J=1,3) )1,3, 2,3, 3,3, 4,3, 5,3, 6,3, 7,3, 8,3, 9,3, 10,3, 11,3, 12,3, 13,3, 14,3, （中间数据省略，其形式与上类同）50,3, 51,3, 52,3, 53,3, 1,1, 1,2, 2,2, 3,2, 4,2, 5,2, 6,2, 7,2, 8,2, （中间数据省略，其形式与上类同）46,1, 47,1, 48,1, 49,1, 50,1, 51,1, 52,2, (JFI(I,J),J=1,2),I=1,NFI)50,52 NLM,NP1,10,98.5,1.0,152,10,98.5,1.0,05,NJP1,2,-53，016,2,-165.18438,2,165.184，052,2,- 1, 2, 3, 4, 5, 6, 7, 8, 9, , , 49，50，51，52，53. 3.2.2 计算结果（1）文件.OUT（部分结果）ICA= 1截面最大轴力最小轴力最大剪力最小剪力最大弯矩最小弯矩1-1.25E-12-1.50E-123.33E+031.75E+03-6.34E-12-7.60E-122-3.98E-13-4.78E-132.51E+031.12E+038.73E+034.32E+033-1.36E-12-1.64E-121.68E+034.72E+021.50E+046.78E+034-1.28E-11-1.53E-118.62E+02-1.76E+021.86E+047.38E+0353.65E-113.04E-116.02E+02-3.92E+021.92E+047.16E+036-2.54E-11-3.05E-112.40E+02-8.09E+021.95E+046.74E+037-1.18E-11-1.41E-11-9.06E+02-2.13E+031.89E+043.23E+038-8.70E-11-1.04E-10-2.08E+03-3.52E+031.15E+04-5.71E+039-1.24E-10-1.49E-104.84E+033.15E+03-1.63E+04-4.27E+0410-1.16E-10-1.39E-106.20E+034.25E+03-3.62E+04-6.74E+0411-1.20E-10-1.44E-109.84E+037.25E+03-6.81E+04-1.06E+0512-8.40E-11-1.01E-101.25E+049.41E+03-9.61E+04-1.41E+0513-1.00E-10-1.20E-101.38E+041.04E+04-1.27E+05-1.79E+0514-8.47E-11-1.02E-101.51E+041.15E+04-1.60E+05-2.21E+0515-1.01E-10-1.21E-101.66E+041.27E+04-1.97E+05-2.68E+05168.86E-117.38E-11-1.10E+04-1.44E+04-1.62E+05-2.23E+05178.27E-116.89E-11-9.85E+03-1.30E+04-1.30E+05-1.83E+05189.67E-118.06E-11-8.83E+03-1.17E+04-1.02E+05-1.47E+05197.43E-116.19E-11-7.89E+03-1.05E+04-7.62E+04-1.14E+05208.21E-116.84E-11-6.72E+03-9.06E+03-4.71E+04-7.81E+04217.01E-115.84E-11-5.63E+03-7.69E+03-2.23E+04-4.78E+04222.76E-112.30E-11-3.35E+03-4.90E+03-6.57E+03-2.89E+04239.05E-117.55E-11-2.14E+03-3.42E+037.09E+03-1.38E+04248.56E-117.14E-11-9.86E+02-2.01E+031.48E+04-5.64E+03253.17E-112.64E-111.32E+02-6.59E+021.65E+04-3.96E+03265.60E-114.67E-113.55E+02-3.94E+021.66E+04-3.79E+03279.36E-117.80E-116.81E+02-1.15E+021.65E+04-3.99E+03285.34E-114.45E-115.91E+02-1.94E+021.47E+04-5.86E+0329-3.20E-11-3.83E-112.00E+039.60E+026.82E+03-1.42E+0430-1.28E-10-1.53E-103.48E+032.17E+03-6.95E+03-2.95E+0431-1.25E-10-1.50E-104.76E+033.20E+03-2.28E+04-4.85E+0432-1.59E-10-1.91E-107.64E+035.55E+03-4.76E+04-7.90E+0433-1.41E-10-1.69E-109.11E+036.71E+03-7.69E+04-1.15E+0534-1.46E-10-1.75E-101.17E+048.86E+03-1.03E+05-1.48E+0535-1.26E-10-1.51E-101.30E+049.88E+03-1.31E+05-1.84E+0536-1.35E-10-1.62E-101.44E+041.10E+04-1.63E+05-2.25E+0537-1.25E-10-1.50E-101.58E+041.21E+04-1.98E+05-2.69E+0538-1.24E-10-1.49E-10-1.13E+04-1.49E+04-1.62E+05-2.23E+0539-1.46E-10-1.76E-10-1.02E+04-1.35E+04-1.29E+05-1.82E+0540-9.42E-11-1.13E-10-9.20E+03-1.23E+04-9.89E+04-1.44E+0541-1.19E-10-1.42E-10-8.24E+03-1.11E+04-7.15E+04-1.11E+0542-1.15E-10-1.38E-10-6.97E+03-9.47E+03-4.09E+04-7.32E+0443-1.34E-10-1.61E-10-5.87E+03-8.12E+03-1.49E+04-4.11E+0444-2.10E-10-2.52E-10-3.29E+03-5.00E+033.85E+02-2.15E+0445-1.57E-10-1.89E-10-2.06E+03-3.50E+031.28E+04-4.57E+0346-1.11E-10-1.33E-10-8.79E+02-2.12E+032.02E+044.21E+0347-4.86E-11-5.83E-114.00E+02-6.28E+021.98E+046.97E+03485.45E-114.54E-116.30E+02-3.79E+021.94E+047.37E+0349-7.38E-12-8.85E-128.94E+02-1.56E+021.88E+047.56E+0350-8.92E-12-1.07E-111.71E+034.92E+021.51E+046.90E+0351-2.73E-12-3.27E-122.54E+031.14E+038.79E+034.38E+03522.05E-121.71E-12-1.14E+03-2.54E+038.79E+034.38E+03532.05E-121.71E-123.36E+031.77E+034.42E-113.68E-113.2.3 图形示意：状态荷载剪力-1.50E+04-1.00E+04-5.00E+030.00E+005.00E+031.00E+041.50E+04091630415059708491106118127136146159170177系列2关心截面内力影响线左支点内力图左支点剪力图左支点弯矩图左支点1/4截面内力图左支点1/4截面剪力图左支点1/4截面弯矩图左1/2跨截面内力图左1/2跨截面剪力图左1/2跨截面弯矩图左截面3/4内力影响线左截面3/4剪力影响线左截面3/4弯矩影响线跨中支点截面内力影响线跨中支点截面剪力影响线跨中支点截面弯矩影响线跨中1/4截面内力图跨中1/4截面剪力图跨中1/4截面弯矩图中跨1/2截面内力影响线中跨1/2截面剪力影响线中跨1/2截面弯矩影响线3.3 支座沉降（SQ2荷载）影响计算考虑两中墩沉降0.02m引起的内力和位移计算。由于采用FR2程序计算，所以由OUTFI子程序输出结点位移时，将位移值置零了。3.3.1 输入数据文件名为chao.DAT52,53,5,32,1,0,1,1,180,1 （NM,NJ,NS,NGE,NME,NKA,NCA,NTI,NFI,NFY） （省略）41,9999,0.0,9999,16,0.0,-0.02,9999,27,9999,-0.02,9999,53,9999,0.0,9999, ( ISJ (SXYM(J),J=1,3) ) （省略）0,0 （NLM,NP)0 （NJP）3.3.2 计算结果（chao.DED）180 31 1 3 .00000E+00 .00000E+00 .00000E+00 .0002 2 3 .00000E+00 .00000E+00 .00000E+00 3.0003 3 3 .00000E+00 .00000E+00 .00000E+00 6.000 （中间数据省略，其形式与上类同）51 51 3 .00000E+00 .00000E+00 .00000E+00 346.00052 52 3 .00000E+00 .00000E+00 .00000E+00 349.00053 53 3 .00000E+00 .00000E+00 .00000E+00 352.00052 1 1 -.62936E+00 .48162E+02 -.80083E-02 .00053 1 2 -.62936E+00 .48162E+02 .14441E+03 3.00054 2 2 -.88297E+00 .47977E+02 .28833E+03 6.00055 3 2 -.12632E+01 .47952E+02 .43234E+03 9.000 （中间数据省略，其形式与上类同）171 51 1 -.14014E+01 -.52937E+02 .47588E+03 343.000174 51 1 -.99334E+00 -.52803E+02 .31717E+03 346.000177 52 1 -.68180E+00 -.52898E+02 .15861E+03 349.000180 52 2 -.68180E+00 -.52898E+02 -.16070E-01 352.0003.3.3 图形示意3.4 基本可变荷载（人群、汽车）内力和位移计算影响线数据文件bysj.DA2，运行（修改后的）ADLOAD程序后，键入计算问题名zhou，再键入：1.0, 1.0 （DX，DA）150, 10.5, 1（L-计算跨径，Q-人群荷载，NJ-公路级别）计算结果文件为zhou.SQ1，内容为（部分内容）：1 0 1 .34268E-03 .00000E+00 .14592E-03 .00000E+00 .00000E+00 .00000E+00.34268E-03 .00000E+00 .14592E-031 1 1 .47666E-03 .00000E+00 .20297E-03.00000E+00 .00000E+00 .00000E+00 .47666E-03 .00000E+00 .20297E-031 0 2 -.39822E-03 .00000E+00 .20600E-03 .00000E+00 .00000E+00 .00000E+00.39822E-03 .00000E+00 -.20600E-031 1 2 -.39822E-03 .00000E