预应力混凝土连续刚构桥毕业设计.doc

预应力混凝土连续刚构桥第一部分方案简介及上部结构尺寸拟定一 本设计经方案比选后，桥跨布置为：全桥采用80米+135米+80米预应力混凝土变截面连续刚构结构，全长295米。上部结构桥面宽采用净9+2*1.5 m。截面形式采用单箱单室。图1 桥位地形图二 桥型布置1. 主跨径的拟定主跨径定为135m，边跨采用0.59倍的中跨径 80m，桥梁全长为：80+135+80=295(m)2顺桥向梁的尺寸拟定（1） 墩顶处梁高：根据规范，梁高为1/161/20L，取L/18.75, 约取偏安全的7.2 m。（2） 跨中梁高：根据规范，梁高为 L/45,即3.0 m。（3） 梁底曲线：选用二次抛物线。以跨中梁底为原点，曲线方程：Y=-0.0011008X2。3 横桥向的尺寸拟定根据任务书规定，行车道为净-9m，另外两边各有宽1.5m的人行道。图2 主梁截面尺寸图顶板厚取28cm；跨中处底板厚32cm，以便布置预应力束，支点处底板厚为 120cm,中间底板板厚成抛物线性变化；腹板厚度由于要布置预应力钢束锚头，故采用70cm；顶板承托尺寸采用45cmX45cm和30cmX60cm,底板承托尺寸采用45cm45cm；横隔板共设4道，两支点各两道，厚度取100cm，板上留有人孔，尺寸为200cm200cm；人行道板具体尺寸如图3所示。 图3 人行道板构造4.桥面铺装 桥面铺装：根据桥梁工程（上）选用8cm厚的防水混凝土作为铺装层，上加2cm厚的沥青混凝土磨耗层，共计10cm厚。 桥面横坡：根据规范规定为1.5%3.0%,取2.0%,该坡度由箱梁顶板坡度控制。5下部构造桥墩采用双薄壁形式，桥墩壁厚3.0米，宽7米，两壁中心距为7米。基础均为桩基础。桥台为埋置式桥台，放置在基岩上。三施工要点及注意事项1.桥梁上部采用挂篮悬臂浇注施工，施工时要对称浇注，应注意立摸高程的合理设置，准确控制悬浇高程，主梁边中跨合拢高差应控制在cm以内。2.施工后的主梁备用预应力束孔处理如下：顶板束孔灌浆封填，底板束孔留下备用，但不穿预应力束。3.箱梁悬浇施工时在底板上的施工孔不封堵，作为箱梁的通气孔。四.本桥主要材料参照规范规定，该桥材料取用如下。1混凝土箱梁采用50号，墩身采用40号，承台、盖梁、耳背墙、防撞护栏、人行道采用30号。2钢材1) 纵、横向预应力采用ASTMA416-92-270级钢绞线，标准强度为1860Mpa，直径为15.24mm，面积140mm2,弹性模量为1.9105 Mpa，采用OVM锚具。2) 带肋钢筋应符合钢筋混凝土用热轧带肋钢筋GB1499-91的规定、光圆钢筋应符合钢筋混凝土用热轧光圆钢筋GB1499-91的规定。3伸缩缝伸缩缝采用HXC-80A定型产品 。4桥梁支座桥台处安装一个GPZ单向活动和双向活动盆式支座。五桥梁设计荷载根据设计任务书规定：荷载等级为汽车-20级、挂车-100级、人群荷载为3.0kN/m2。第二部分 内力计算与荷载组合一全桥结构计算图式的确定 本设计的单元划分，每一个施工阶段自然划分为一个单元。这样便于模拟施工过程，而且这些截面正是需要验算的截面。另外，在墩顶、跨中和一些构造变化位置相应增设了几个单元。这样整个主桥划分成98个单元，99个截面，如图4所示。图4 主桥单元划分示意图（尺寸单位：m）二全桥施工阶段的划分1为了方便全桥的施工分段，更好地根据起吊重量来划分，特用程序将划分的梁的单元的截面特性和单元重量计算出来，具体结果见表1：表1 截面特性及单元重量计算结果表单元号左梁高（m）左面积(m2)右梁高（m）右面积(m2)单元重量(kN)13.08.453.08.452.64e+0323.08.453.18.5932033.18.593.449.041.1e+0343.449.043.779.51.16e+0353.779.54.119.961.22e+0364.119.964.4410.41.27e+0374.4410.44.7110.81.06e+0384.7110.84.9811.11.1e+0394.9811.15.2512.51.18e+03105.2512.55.4513.6981115.4513.65.6514.01.04e+03125.6514.05.8614.31.06e+03135.8614.36.0214.6905146.0214.66.1914.9923156.1914.96.3615.2941166.3615.26.5315.5959176.5315.56.715.8978186.715.86.8616.1996196.8616.17.0316.41.01e+03207.0316.47.216.71.03e+03217.216.77.216.71.25e+03227.216.77.216.72.91e+03237.216.77.216.41.03e+03247.0316.46.8616.11.01e+03256.8616.16.715.8996266.715.86.5315.5978276.5315.56.3615.2380286.3615.26.1914.9941296.1914.96.0214.6923306.0214.65.8614.3905315.8614.35.6514.01.06e+03325.6514.05.4513.61.04e+03335.4513.65.2512.5981345.2512.54.9811.11.18e+03354.9811.14.7110.81.1e+03364.7110.84.4410.41.08e+03374.4410.44.119.961.27e+03384.119.963.779.51.22e+03393.779.53.449.041.16e+03403.449.043.18.591.1e+03413.18.593.08.45320423.08.453.18.59320433.18.593.449.041.1e+03443.449.043.779.51.16e+03453.779.54.119.961.22e+03464.119.964.4410.41.27e+03474.4410.44.7110.81.06e+03484.7110.84.9811.11.1e+03494.9811.15.2512.51.18e+03505.2512.55.4513.6981515.4513.65.6514.01.04e+03525.6514.05.8614.31.06e+03535.8614.36.0214.6905546.0214.66.1914.9923556.1914.96.3615.2941566.3615.26.5315.5959576.5315.56.715.8978586.715.86.8616.1996596.8616.17.0316.41.01e+03607.0316.47.216.71.03e+03617.216.77.216.71.25e+03627.216.77.216.72.91e+03637.216.77.0316.41.03e+03647.0316.46.8616.11.01e+03656.8616.16.715.8996666.715.86.5315.5978676.5315.56.3615.2959686.3615.26.1914.9941696.1914.96.0214.6923706.0214.65.8614.3905715.8614.35.6514.01.06e+03725.6514.05.4513.61.04e+03735.4513.65.2512.5981745.2512.54.9811.11.18e+03754.9811.14.7110.81.1e+03764.7110.84.4410.41.06e+03774.4410.44.119.961.27e+03784.119.963.779.51.22e+03793.779.53.449.041.16e+03803.449.043.18.591.1e+03813.18.593.08.45320823.012.03.012.02.64e+03833.012.03.012.02.4e+03843.012.03.012.02.4e+03853.012.03.012.02.4e+03863.012.03.012.02.22e+03873.012.03.012.02.4e+03883.012.03.012.02.4e+03893.012.03.012.02.4e+03903.012.03.012.02.4e+03913.012.03.012.02.4e+03923.012.03.012.02.4e+03933.012.03.012.02.4e+03943.012.03.012.02.4e+03953.012.03.012.02.4e+03963.012.03.012.02.4e+03973.012.03.012.02.4e+03983.012.03.012.02.4e+032横隔板重量的计算 横隔板重： Q=(622600-212026-22020-10590-200200) 8010-626=792(kN)3桥面铺装和人行道板每米重量计算 Q=90.125+40.323=55(kN/m)4主跨施工分段 施工分段见图4。全桥共分98个单元（82个桥面单元）、99个节点，其中两个边跨各有20个单元，中跨有19个单元，再后面的恒载、活载、施工及验算等内力的计算时，代入程序的单元划分形式都以以上这种划分方式填写数据文件。图5 主梁施工分段三 恒载内力计算恒载内力主要包括一期恒载和二期恒载的内力叠加。全桥主要施工阶段的内力如图6所示。1悬臂浇注阶段：在支架或托架上浇注3号梁段，拼装挂篮，悬臂浇注各箱梁梁段并张拉相应顶板纵向预应力束，悬臂浇注结束时全桥的恒载内力如表2所示。表2 最大悬臂阶段内力计算结果表单元号节点号轴力剪力弯矩331.37e+0043.29e+0036.66e+00441.5e+0041.1e+0031.62e+004442.619e+0041.369e+0033.465e+00452.86e+0042.17e+0032.52e+004554.34e+0049644.36e+00464.49e+0043.48e+0034.8e+004665.84e+004-2406.19e+00476.0e+0044.75e+0036.35e+004777.29e+004-8827.92e+00487.49e+0045.81e+0038.43e+004888.35e+004-3.23e+0039.31e+00498.51e+0046.91e+0038.96e+004999.43e+004-4.54e+0039.27e+004109.51e+0045.71e+0038.9e+00410101.04e+005-2.84e+0039.12e+004111.05e+0054.94e+0039.43e+00411111.14e+005-1.87e+0039.53e+004121.15e+0055.57e+0031.01e+00512121.25e+005-2.95e+0031.01e+005131.26e+0056.8e+0031.04e+00513131.36e+005-4.48e+0031.03e+005141.37e+0056.73e+0031.05e+00514141.47e+005-4.72e+0031.02e+005151.48e+0057.27e+0031.04e+00515151.58e+005-5.47e+0039.92e+004161.59e+0057.64e+0031.01e+00416161.69e+005-5.5e+0039.51e+004171.7e+0057.71e+0039.8e+00417171.8e+005-4.96e+0039.07e+004181.81e+0057.13e+0039.58e+00518181.9e+005-3.26e+0038.54e+004191.9e+0055.22e+0049.59e+0041919191.98e+0051868.43e+004201.99e+0052.48e+0031.03e+00520202.1e+005-2.48e+0031.2e+005212.13e+0051.01e+0041.34e+00521212.13e+005-1.01e+0041.34e+005223.365e+0053.403e+0047.255e+00522222.14e+0052.46e+0041.08e+005232.14e+0052.64e+0047.54e+0052边跨合龙阶段：安装排架并按施工要求进行预压，现浇边跨等高粱段，达到强度要求后，浇注边跨合龙段，张拉边跨底板纵向预应力束。此时全桥恒载内力如表3所示。表3 边跨合龙阶段内力计算结果表单元号节点号轴力剪力弯矩117.510e+0043.051e+003-1.401e+00327.645e+004-1.113e+0021.888e+004227.645e+004-6.208e+0031.888e+00437.671e+0046.544e+0031.304e+004339.004e+004-3.346e+0031.952e+00449.213e+0047.193e+0031.152e+004441.054e+005-4.003e+0032.033e+00451.072e+0058.373e+0031.048e+004551.204e+005-5.196e+0032.166e+00461.225e+0059.617e+0039.445e+003661.358e+005-6.421e+0032.318e+00471.375e+0051.089e+0049.184e+003771.503e+005-7.053e+0032.474e+00481.320e+0051.052e+0044.683e+004881.406e+005-7.957e+0035.856e+00491.223e+0051.028e+0047.991e+004991.314e+005-7.923e+0038.305e+004101.103e+0057.761e+0031.099e+00510101.192e+005-4.893e+0031.122e+005111.001e+0055.794e+0031.502e+00511111.089e+005-2.725e+0031.512e+005121.104e+0056.426e+0031.535e+00512121.197e+005-3.801e+0031.535e+005131.214e+0057.654e+0031.541e+00513131.311e+005-5.333e+0031.528e+005141.320e+0057.583e+0031.518e+00514141.418e+005-5.573e+0031.489e+005151.429e+0058.118e+0031.482e+00515151.531e+005-6.323e+0031.437e+005161.540e+0058.493e+0031.429e+00516161.639e+005-6.350e+0031.371e+005171.650e+0058.558e+0031.374e+00517171.748e+005-5.812e+0031.302e+005181.756e+0057.985e+0031.326e+00518181.849e+005-4.112e+0031.223e+005191.856e+0056.073e+0031.302e+00519191.933e+005-6.681e+0021.186e+005201.943e+0053.341e+0031.351e+00520202.048e+005-3.341e+0031.514e+005212.084e+0051.097e+0041.632e+00521212.084e+005-1.097e+0041.632e+005222.090e+0053.711e+0047.856e+00422222.113e+0051.027e+0041.066e+005232.109e+0051.861e+0041.193e+005中跨合龙阶段：拼装中跨合龙吊架，焊接合龙段骨架，绑扎合龙段钢筋，浇注中跨合龙段，张拉中跨底板纵向预应力束和剩余次中跨底板纵向预应力束。中跨合龙完成后的全桥恒载内力如表4所示。表4 中跨合龙阶段内力计算结果表单元号节点号轴力剪力弯矩117.769e+004-1.976e+003-1.380e+00327.824e+0044.663e+003-4.306e+004227.824e+004-4.663e+003-4.306e+00437.850e+0044.995e+003-4.651e+004339.167e+004-1.834e+003-4.011e+00449.425e+0045.493e+003-3.981e+004441.075e+005-2.317e+003-3.104e+00451.094e+0056.683e+003-3.222e+004551.226e+005-3.519e+003-2.109e+00461.248e+0057.936e+003-2.469e+004661.380e+005-4.753e+003-1.101e+00471.399e+0059.214e+003-1.645e+004771.526e+005-5.397e+003-9.623e+00281.349e+0058.886e+0032.724e+004881.434e+005-6.332e+0033.893e+00491.255e+0058.668e+0036.652e+004991.346e+005-6.324e+0036.965e+004101.139e+0056.185e+0031.028e+00510101.227e+005-3.324e+0031.050e+005111.040e+0054.242e+0031.475e+00511111.127e+005-1.179e+0031.486e+005121.142e+0054.875e+0031.559e+00512121.235e+005-2.255e+0031.558e+005131.251e+0056.102e+0031.615e+00513131.348e+005-3.785e+0031.602e+005141.357e+0056.033e+0031.634e+00514141.455e+005-4.027e+0031.605e+005151.466e+0056.569e+0031.639e+00515151.567e+005-4.777e+0031.595e+005161.576e+0056.945e+0031.629e+00516161.675e+005-4.806e+0031.570e+005171.685e+0057.013e+0031.615e+00517171.783e+005-4.271e+0031.543e+005181.791e+0056.444e+0031.609e+00518181.884e+005-2.577e+0031.506e+005191.890e+0054.540e+0031.626e+00519191.967e+0058.568e+0021.510e+005201.977e+0051.824e+0031.716e+00520202.081e+005-1.824e+0031.879e+005212.117e+0059.440e+0032.037e+00521212.117e+005-9.440e+0032.037e+005222.123e+0053.713e+0041.203e+00522222.103e+005-7.242e+0031.963e+005232.102e+0053.768e+0048.416e+0044桥面铺装阶段：桥面铺装、人行道板等桥面系安装完毕大桥建成后的全桥恒载内力如表5所示。表5 桥面铺装阶段内力计算结果表单元号节点号轴力剪力弯矩117.697e+004-6.359e+002-1.374e+003127.755e+0044.013e+003-3.062e+004227.755e+004-4.013e+003-3.062e+004237.781e+0044.426e+003-3.320e+004339.094e+004-1.275e+003-2.681e+004349.356e+0045.209e+003-2.461e+004441.068e+005-2.042e+003-1.587e+004451.087e+0056.674e+003-1.647e+004551.218e+005-3.519e+003-5.377e+003561.240e+0058.202e+003-9.775e+003661.372e+005-5.028e+0033.864e+003671.391e+0059.755e+003-3.737e+003771.518e+005-5.947e+0031.172e+004781.342e+0059.659e+0033.693e+004881.427e+005-7.110e+0034.860e+004891.250e+0059.672e+0037.233e+004991.341e+005-7.331e+0037.546e+0049101.137e+0057.421e+0031.039e+00510101.225e+005-4.563e+0031.061e+00510111.039e+0055.653e+0031.444e+00511111.126e+005-2.593e+0031.454e+00511121.141e+0056.451e+0031.483e+00512121.234e+005-3.833e+0031.482e+00512131.250e+0057.842e+0031.490e+00513131.347e+005-5.528e+0031.476e+00513141.356e+0057.911e+0031.463e+00514141.454e+005-5.907e+0031.435e+00514151.465e+0058.585e+0031.421e+00515151.566e+005-6.795e+0031.376e+00515161.576e+0059.099e+0031.359e+00516161.675e+005-6.962e+0031.300e+00516171.685e+0059.304e+0031.290e+00517171.783e+005-6.566e+0031.218e+00517181.791e+0058.874e+0031.226e+00518181.883e+005-5.012e+0031.122e+00518191.891e+0057.109e+0031.181e+00519191.967e+005-1.721e+0031.065e+00519201.977e+0054.531e+0031.205e+00520202.082e+005-4.531e+0031.368e+00520212.118e+0051.228e+0041.458e+00521212.118e+005-1.228e+0041.458e+00521222.124e+0054.092e+0045.215e+00422222.105e+005-8.609e+0031.304e+00522232.105e+0054.023e+0045.940e+003 图6 主梁主要施工阶段内力图a)最大悬臂阶段内力；b)边跨合龙阶段内力；c)中跨合龙阶段内力；d)桥面铺装阶段内力四 温度及支座沉降次内力计算 （一）温度次内力计算方法及结果 按矩阵位移法求解温度次内力。本设计考虑主梁上下缘温差5，温度次内力结果如图7所示。（二）支座沉降次内力计算方法及结果由于各个支座处的竖向支座反力和地质条件的不同引起支座的不均匀沉降，连续体系是一种对支座不均匀沉降特别敏感的结构，所以由它引起的内力是构成内力的重要组成部分. 按矩阵位移法求解支座沉降次内力。在桥梁设计中，支座沉降工况的选取是应慎重考虑的问题。一般应综合考虑桥址处的地质、水文等情况，根据已建桥梁的设计经验来定。有时需选取几种沉降工况计算，这样就存在一个工况组合的问题。程序一般对每一个截面挑最不利的工况内力值作为沉降次内力。 本设计考虑1号墩下降1 .0cm，0号桥台下降1.0cm。沉降次内力如图8所示。五.活载内力计算（一）影响线的计算将单位荷载P=1作用在各桥面的节点上，求得结构的变形及内力，可得位移影响线和内力影响线。（二）人群、履带车、挂车加载人群加载只需求出影响的正、负区段面积；履带车离散为若干集中力；挂车按集中荷载加载。（三）汽车加载挂车、履带车全桥只考虑一辆。汽车荷载是由主车和重车组成的车队，车距又受到约束，求其最大、最小效应是个较复杂的问题。这种情况下，车辆数和车距都是未知参数，随具体影响线而变化，问题归结为求具有多个变量的函数在约束条件下的极值。此问题的解决借助于计算机程序完成。全桥活载内力如图9所示。1 汽车最大、最小弯矩如表6所示。表6 汽车荷载效应汽车MaxM结果:单元号节点号轴力剪力弯矩110.000e+0000.000e+0000.000e+00020.000e+000-1.801e+0024.171e+003220.000e+0001.801e+0024.171e+00330.000e+000-2.744e+0024.442e+003330.000e+0001.544e+0024.442e+00340.000e+000-1.984e+0025.053e+003440.000e+0007.837e+0015.054e+00350.000e+000-1.322e+0025.453e+003550.000e+0001.220e+0015.453e+00360.000e+000-7.885e+0015.507e+003660.000e+000-4.115e+0015.507e+00370.000e+0008.980e+0015.167e+003770.000e+000-8.979e+0015.167e+00380.000e+0001.336e+0024.665e+003880.000e+000-1.336e+0024.665e+00390.000e+0001.818e+0024.013e+003990.000e+000-1.818e+0024.013e+003100.000e+0007.412e+0013.279e+00310100.000e+000-7.412e+0013.279e+003110.000e+0002.096e+0022.738e+00311110.000e+000-2.096e+0022.738e+003120.000e+0001.274e+0022.348e+00312120.000e+000-1.274e+0022.348e+003130.000e+0001.372e+0021.958e+00313130.000e+000-1.372e+0021.958e+003140.000e+0001.450e+0021.638e+00314140.000e+000-1.450e+0021.638e+003150.000e+0003.353e+0011.348e+00315150.000e+000-1.535e+0021.348e+003160.000e+0001.589e+0021.045e+00316160.000e+000-1.589e+0021.045e+003170.000e+000-1.245e+0018.093e+00217170.000e+000-1.075e+0028.093e+002180.000e+000-8.945e+0006.038e+00218180.000e+0008.946e+0006.039e+002190.000e+0001.129e+0024.318e+00219190.000e+000-1.129e+0024.317e+002200.000e+000-3.778e+0002.897e+00220200.000e+0003.778e+0002.898e+002210.000e+0001.179e+0021.631e+00221210.000e+000-1.179e+0021.630e+002220.000e+0007.367e+0010.000e+0002222-5.999e+001-1.304e+0028.754e+002230.000e+0000.000e+0000.000e+000汽车MinM结果:单元号节点号轴力剪力弯矩110.000e+0000.000e+0000.000e+000120.000e+0003.393e+001-4.242e+002220.000e+000-3.393e+001-4.242e+002230.000e+0003.393e+001-4.751e+002330.000e+000-3.393e+001-4.751e+002340.000e+0003.407e+001-6.474e+002440.000e+000-3.407e+001-6.474e+002450.000e+0003.407e+001-8.178e+002550.000e+000-3.407e+001-8.178e+002560.000e+0003.380e+001-1.013e+003660.000e+000-3.324e+001-1.013e+003670.000e+0003.320e+001-1.211e+003770.000e+000-3.320e+001-1.211e+003780.000e+0003.320e+001-1.372e+003880.000e+000-3.320e+001-1.372e+003890.000e+0003.320e+001-1.518e+003990.000e+000-3.320e+001-1.518e+0039100.000e+0009.538e+001-1.850e+00310100.000e+000-9.512e+001-1.850e+00310110.000e+0001.713e+002-2.197e+00311110.000e+000-1.713e+002-2.197e+00311120.000e+0002.387e+002-2.921e+00312120.000e+000-2.387e+002-2.921e+00312130.000e+0002.757e+002-3.684e+00313130.000e+000-2.757e+002-3.684e+00313140.000e+0003.822e+002-4.503e+00314140.000e+000-3.822e+002-4.503e+00314150.000e+0004.058e+002-5.483e+00315150.000e+000-4.058e+002-5.483e+00315160.000e+0004.283e+002-6.513e+00316160.000e+000-4.283e+002-6.513e+00316170.000e+0004.501e+002-7.604e+00317170.000e+000-4.501e+002-7.604e+00317180.000e+0005.631e+002-8.820e+00318180.000e+000-5.631e+002-8.820e+00318190.000e+0005.761e+002-1.024e+00419190.000e+000-5.761e+002-1.024e+00419200.000e+0006.137e+002-1.172e+00420200.000e+000-6.137e+002-1.172e+00420210.000e+0006.137e+002-1.325e+00421210.000e+000-6.137e+002-1.325e+00421220.000e+0006.374e+002-1.515e+00422226.316e+001-3.032e+001-1.519e+00422239.900e+0014.990e+002-1.792e+004 汽车MaxQ结果:单元号节点号轴力剪力弯矩110.000e+0004.605e+0020.000e+000120.000e+000-2.924e+0023.656e+003220.000e+0002.924e+0023.646e+003230.000e+000-