桥渡课程设计

PAGE桥渡课程设计指导书1.桥梁状况桥梁位于I级干线，桥址轴线及梁底标高见图1。桥下河床断面见图2，桥下河床的左滩与主槽分界点为（137.49,31.81）；桥下河床的右滩与主槽分界点为（289.36,31.60）；左滩、主槽、右滩的糙率系数分别为25、40、25。桥梁轴线与水流交角为90度。0号台的墩台线的X坐标为105.14米。图1桥址轴线及梁底标高形态断面形态断面位于桥址上游120米处。形态断面处左滩、主槽、右滩的糙率系数分别为25、50、25。其左滩主槽分界点为（107.01,32.18）；右滩主槽分界点为（281.87,32.18）。桥址与形态断面间的水面坡度为0.005弧度。桥下河底线形态断面图2桥下河底线及形态断面坐标图3桥墩宽度图（墩底顺水流方向长度3.5米）图4基础（圆沉井）尺寸图3号墩地质线标高（米）流量系列年份及流量（立方米/秒）图53号墩地质及流量系列实测其他资料桥型为一般河流的一般大桥；洪水期没有漂浮物和泥石流；测得浪高为0.27米。含砂量特征为5公斤/立方米。桥下表层土为砂卵石。要求计算形态断面水位关系曲线，并画图。计算设计流量，画出流量统计（P-III曲线）图形。检算梁底水位。检算3号桥墩的基础埋置深度。按水文计算要求修改设计（主槽内桥墩基础底标高都按3号墩处理），画出新的设计图。具体设计过程如下：形态断面和桥下河床断面如下：一计算形态断面水位关系曲线（1）利用CAD查询功能直接得出过水断面和湿周，河流水位为时：左滩：河槽：右滩：河流水位为时：左滩：河槽：右滩：河流水位为时：左、右滩：河槽：河流水位为时：左、右滩：河槽：他水位点的计算同上，将各水位点的计算结果列表如下：水位(m)过水面积ωm22湿周Pmm水力半径RmVm/ss流量Qmm3/s39.96左滩97.473109.20110.8931.639159.7400右滩149.842227.3335.4825.496823.5388主槽1928.7118175.972210.96017.44533646.4488合计2176.0332//15.91434629.776639.87左滩88.181101.70440.8671.607141.7399右滩147.616627.1965.4285.460805.9566主槽1912.9880175.972210.87117.35033190.1169合计2148.7777//15.88734137.886339.37左滩48.82760.1080.8121.53975.147右滩135.423326.4335.1235.254711.4499主槽1825.5550175.972210.37416.81730700.7702合计2009.8001//15.66731487.229838.87左滩34.35018.5111.8562.66991.694右滩123.518825.6714.8125.038622.3255主槽1738.1220175.97229.87716.27628289.4484合计1895.9888//15.29729003.550238.37左滩25.63110.3392.4793.23882.994右滩111.901124.9084.4934.813538.5866主槽1650.6990175.97229.38015.72525957.8805合计1788.2222//14.86426579.338537.87左滩21.6589.5042.2793.06166.299右滩100.571124.1454.1654.576460.2544主槽1563.2660175.97228.88415.16523707.0047合计1685.4889//14.37824233.660037.37左滩18.0198.6692.0792.87951.878右滩89.53023.3823.8294.327387.3622主槽1475.8330175.97228.38714.59421538.6690合计1583.3779//13.88021977.993136.87左滩14.7147.8341.8782.69139.598右滩78.77722.6193.4834.062319.9666主槽1388.4000175.97227.89014.01219454.3338合计1481.8991//13.37119813.9902续上表水位(m)过水面积ωm22湿周Pmm水力半径RmVm/ss流量Qmm3/s36.37左滩11.7446.9991.6782.49629.316右滩68.31221.8573.1253.779258.1455主槽1300.9770175.97227.39313.41717455.7713合计1381.0226//12.84817743.117535.87左滩9.1086.1631.4782.29420.890右滩58.13521.0942.7563.475202.0144主槽1213.5440175.97226.89612.80915544.6699合计1280.7883//12.31115767.660235.37左滩6.8075.3281.2782.08114.168右滩48.24620.3312.3733.145151.7344主槽1126.1110175.97226.39912.18713723.3351合计1181.1663//11.75913889.225434.87左滩4.8414.4931.0771.8588.992右滩38.64519.5681.9752.783107.5333主槽1038.6880175.97225.90311.54711993.9938合计1082.1666//11.19112110.446334.37左滩3.2083.6580.8771.6205.197右滩29.33218.8061.5602.37869.737主槽951.2500175.97225.40610.89010358.9972合计983.7900//10.60610433.990633.87左滩1.9112.8230.6771.3632.604右滩20.30718.0431.1251.91338.841主槽863.8200175.97224.90910.2128821.2666合计886.0388//10.0038862.711033.37左滩0.9471.9880.4771.0791.022右滩11.57017.2800.6701.35315.653主槽776.3900175.97224.4129.5117384.0008合计788.9077//9.3817400.688332.87左滩0.3191.1530.2760.7500.239右滩3.96511.5140.3440.8693.444主槽688.9600175.97223.9158.7836050.8339合计693.2444//8.7346054.5222水位(m)过水面积ωm22湿周Pmm水力半径RmVm/ss流量Qmm3/s32.37左滩0.0240.3170.0760.3170.008右滩0.3013.1710.0950.3680.111主槽601.5300175.97223.4188.0234826.0006水位(m)过水面积ωm22湿周Pmm水力半径RmVm/ss流量Qmm3/s合计601.8555//8.0194826.122431.87左滩00000右滩00000主槽516.3722161.26773.2027.6813966.0887合计516.3722//7.6813966.088731.37左滩00000右滩00000主槽442.1311139.55773.1687.6263371.8779合计442.1311//7.6263371.877930.87左滩00000右滩00000主槽373.7188135.91662.7506.9392593.2772合计373.7188//6.9392593.277230.37左滩00000右滩00000主槽307.0555132.27552.3216.1981903.2660合计307.0555//6.1981903.266029.87左滩00000右滩00000主槽242.1444128.63441.8825.3901305.1887合计242.1444//5.3901305.188729.37左滩00000右滩00000主槽178.9822124.99331.4324.492803.9211合计178.9822//4.492803.921128.87左滩00000右滩00000主槽117.5711121.35220.9693.462406.9966合计117.5711//3.462406.9966续上表水位(m)过水面积ωm22湿周Pmm水力半径RmVm/ss流量Qmm3/s28.37左滩00000右滩00000主槽57.910117.71110.4922.203127.5966合计57.910//2.203127.5966将以上各水位时的水位流量点、水位流速点和水位过水断面面积点绘于下图，得出水位、流量、流速、过水面积关系曲线。二计算设计流量，画出流量统计（P-Ⅲ曲线）图形（2）按题目中所给流量把大于的流量视为特大洪水，该流量系列中有连续年的观测资料（）,有特大洪水资料（）年，其中有个特大洪水与连续观测资料中q重复。系列中有年资料空缺，将其补齐，使之成为连续系列（）。1、特大洪水的考证期N2、经验频率估算对于5项特大洪水,有对于其余项观测洪水有将计算汇总于下表：流量按大小递减顺序排列顺序号(m)按年份顺序排列列按流量大小排列列经验频率(%))年份流量(m3/s)年份流量(m3/s)12345611930180001930180002.0421931178001931178004.0831960150001960150006.12419619081967119008.165196298071962980710.206196323161977869015.827196467541964675421.438196534211971675027.049196656781968570032.65101967119001966567838.2711196857001973564343.8812196932161974430049.4913197018111965342155.1014197167501976342160.7115197222311969321666.3316197356431963231671.9417197443001975231177.5518197523111972223183.1619197634211970181188.782019778690196190894.393、统计参数估算对于空缺的28项，假定这28项的平均值等于连续系列（不计重迭值）的平均值，其均方等于连续系列（不计重迭值）的均方差，这样补齐后，组成连续的计算系列（）。计算系列的总流量由三部分组成。第一部分为特大洪水系列QT之和，即：第二部分为实测系列（不计重迭的2项）qj之和，即：测系列（不计重迭的3项）的平均值：第三部分为补齐28项空缺值之和计算系列的总流量为：计算系列的平均值为：计算系列的离差差系数为：：4、设计流量计算算理论频率曲线计计算表P(%)0.5125101520507590954.153.52.851.981.531.090.64-0.28-0.69-0.94-1.024.0883.6043.1202.4732.1381.8111.4760.7920.4870.3010.24121591190361648213063112959565779741822570158812744.373.662.9321.531.060.59-0.32-0.66-0.869-0.9144.4963.9283.3442.62.2241.8481.4720.7440.4720.3050.2692374820748176631373311747976177753930249316101420将这组理论频率率曲线绘制制在海森几几率格纸上上。如下图：选择一条最合适适的曲线，在在图中以，，的曲线与与经验点群群吻合得较较好，最终终确定其为为选定的理理论频率曲曲线。按Ⅰ级铁路干干线桥梁计计算，其设设计洪水频频率为则设计流量三检算梁底水位根据形态断面水水位关系曲曲线可知，形形态断面处处设计水位位为，桥断断面位于其其下1200m处，水水面坡度为为0.