【《某预应力混凝土连续梁桥次内力计算及内力组合分析案例》1900字】

某预应力混凝土连续梁桥次内力计算及内力组合分析案例目录TOC\o"1-3"\h\u29887某预应力混凝土连续梁桥次内力计算及内力组合分析案例 1259341.1次内力计算 1141571.1.1温度次内力计算 1136301.1.2支座沉降次内力计算 27171.1.3预加力引起的二次力矩 367601.1.4收缩徐变次内力计算 539521.2内力组合 617241.2.1承载能力极限状态效应组合 7163531.2.2正常使用极限状态效应组合 81.1次内力计算预应力混凝土连续梁桥在施工阶段，一期恒载、二期恒载和预应力荷载由恒载作用转换为施工阶段荷载作用，次内力值也会相应变化。1.1.1温度次内力计算根据《公路桥涵设计通用规范》4.3.12条，设置正温差T1=14℃，T2=5.5℃，T3=0，负温差T1=-7℃，T2=-2.75℃，T3=0。得到温度梯度产生的次内力结果表格见表1.1，弯矩图和剪力图如1.1至图1.4所示：表1.1温度梯度作用下控制截面内力值截面位置梯度升温梯度降温弯矩（）剪力（）弯矩（）剪力（）111213345697989109118124633.76E+021.50E+042.97E+042.64E+042.24E+041.44E+041.71E+041.99E+042.56E+041.15E+048.85E+021.64E+04-3.76E+02-3.76E+02-3.76E+021.11E+021.11E+021.11E+02-9.96E+01-9.96E+01-9.96E+014.43E+024.43E+021.11E+02-1.88E+02-7.52E+03-1.49E+04-1.32E+04-1.12E+04-7.21E+03-8.53E+03-9.95E+03-1.28E+04-5.75E+03-4.43E+02-8.19E+031.88E+021.88E+021.88E+02-5.56E+01-5.56E+01-5.56E+014.98E+014.98E+014.98E+01-2.21E+02-2.21E+02--5.56E+01图1.1桥面升温弯矩图图1.2桥面升温剪力图图1.3桥面降温弯矩图图1.4桥面降温剪力图1.1.2支座沉降次内力计算支座沉降引起的弯矩图和剪力图如图1.5、图1.6所示。支座沉降引起的内力值见表1.2图1.5支座沉降弯矩包络图图1.6支座沉降剪力包络图表1.2支座沉降作用下控制截面内力值截面位置最大值最小值弯矩（）剪力（）弯矩（）剪力（）111213345697989109118124637.79E+013.12E+031.15E+033.82E+031.23E+035.20E+033.13E+039.53E+021.30E+032.87E+032.20E+024.03E+035.31E+015.31E+015.31E+017.20E+017.20E+017.20E+017.78E+017.78E+017.78E+011.10E+021.10E+027.20E+01-5.31E+01-2.12E+03-4.20E+03-2.27E+03-1.02E+03-4.25E+03-2.66E+03-1.29E+03-3.68E+03-1.67E+03-1.29E+02-3.45E+03-7.79E+01-7.79E+01-7.79E+01-1.70E+01-1.70E+01-1.70E+01-9.38E+01-9.38E+01-9.38E+01-1.43E+01-1.43E+01-1.70E+011.1.3预加力引起的二次力矩预加力所引起的二次力矩仅考虑超静定钢束。计算结果见表1.3，弯矩图和剪力图如图1.7和1.8所示。表1.3预加力作用下次内力值单元位置弯矩（）剪力（）单元位置弯矩（）剪力（）1234567891011121314151617181920212223242526272829303132333435363738-4.19E+03-1.67E+04-3.35E+04-5.02E+04-1.70E+04-8.37E+04-1.00E+05-1.17E+05-1.34E+05-1.51E+05-1.67E+05-1.84E+05-2.01E+05-2.18E+05-2.34E+05-2.51E+05-2.68E+05-2.85E+05-3.01E+05-3.18E+05-3.31E+05-3.32E+05-3.23E+05-3.14E+05-3.04E+05-2.94E+05-2.84E+05-2.74E+05-2.64E+05-2.54E+05-2.44E+05-2.34E+05-2.24E+05-2.14E+05-2.04E+05-1.95E+05-1.85E+05-1.75E+054.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+034.19E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+033940414243444546474849505152535455565758596061626364656667686970717273747576-1.65E+05-1.55E+05-1.45E+05-1.35E+05-1.25E+05-1.15E+05-1.05E+05-9.55E+04-8.56E+04-7.56E+04-1.57E+04-5.58E+04-4.59E+04-3.60E+04-2.61E+04-1.62E+04-1.27E+033.64E+031.35E+042.35E+043.34E+044.33E+045.32E+041.31E+047.30E+048.29E+049.28E+041.03E+051.13E+051.23E+051.31E+051.30E+051.21E+051.09E+059.80E+048.65E+047.51E+041.37E+04-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+03-3.30E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+03续表1.3单元位置弯矩（）剪力（）单元位置弯矩（）剪力（）77787980818283848586878889909192939495969798991005.23E+044.08E+042.94E+041.80E+041.56E+03-4.87E+03-1.63E+04-2.77E+04-3.91E+04-5.06E+04-1.20E+04-7.15E+04-7.91E+04-8.67E+04-9.63E+04-1.08E+05-1.19E+05-1.31E+05-1.42E+05-1.53E+05-1.65E+05-1.76E+05-1.88E+05-1.99E+053.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+03101102103104105106107108109110111112113114115116117118119120121122123124-2.11E+05-2.22E+05-2.33E+05-2.45E+05-2.56E+05-2.68E+05-2.79E+05-2.89E+05-2.96E+05-2.95E+05-2.79E+05-2.59E+05-2.38E+05-2.17E+05-1.97E+05-1.76E+05-1.55E+05-1.34E+05-1.14E+05-9.31E+04-7.24E+04-5.17E+04-3.10E+04-1.03E+043.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+033.81E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03-5.17E+03图1.7预加力次内力作用弯矩图图1.8预加力作用剪力图1.1.4收缩徐变次内力计算从主梁浇筑开始，混凝土就已经产生收缩徐变，混凝土收缩和徐变会对结构内力产生影响，因此，计算分析过程要考虑其收缩和徐变。本设计收缩徐变加载为10年，计算分析内力值见1.4,内力图如图1.9至图1.12所示。表1.4混凝土收缩徐变次内力值截面位置混凝土收缩混凝土徐变弯矩（）剪力（）弯矩（）剪力（）111213345697989109118124-7.13E+02-1.96E+011.24E+021.07E+02-3.10E+02-1.71E+02-3.33E+01-3.20E+029.65E+01-9.74E+01-7.07E+02-1.82E+00-2.54E+01-1.80E+003.98E+012.26E+002.27E+004.10E+01-3.31E+00-3.30E+005.07E+011.03E+01-3.54E+03-4.26E+03-9.08E+03-4.25E+03-3.79E+032.62E+032.72E+03-5.46E+02-5.08E+03-3.31E+03-4.44E+034.57E+01-7.73E+014.52E+012.42E+02-7.49E+01-7.60E+013.95E+021.17E+011.08E+013.64E+02-1.04E+00图1.9混凝土收缩弯矩图图1.10混凝土收缩剪力图图1.11混凝土徐变弯矩图图1.12混凝土徐变剪力图1.2内力组合桥梁设计应考虑上部结构可能出现的作用组合，按承载能力极限状态和正常使用极限状态进行作用效应组合，取最不利效应组合设计。1.2.1承载能力极限状态效应组合根据式（3.3）和（3.4）计算承载能力极限状态下的内力值，结果见表1.5，弯矩图和剪力图如图1.13、图1.14所示。表1.5承载能力极限状态下内力值单元位置弯矩M（KN•m）剪力Q（KN）MmaxMminQmaxQmin1112133456979891091181245.97E+03-1.25E+05-1.46E+06-2.22E+053.12E+05-1.03E+06-2.04E+051.31E+05-1.88E+05-4.50E+041.38E+03-3.93E+032.06E+045.80E+04-2.35E+04-1.79E+035.36E+04-1.83E+04-1.06E+034.08E+04-8.04E+035.57E+031.02E+02-2.76E+05-1.67E+06-3.00E+052.11E+05-1.20E+06-3.21E+052.28E+04-8.20E+05-1.28E+05-3.24E+03-1.02E+041.56E+045.16E+04-2.90E+04-1.46E+034.68E+04-2.37E+04-5.88E+033.39E+04-1.24E+043.78E+02,图1.13承载能力极限状态弯矩图图1.14承载额能力极限状态剪力图1.2.2正常使用极限状态效应组合根据式（3.5）和（3.6）计算正常使用极限状态下的内力值。短期效应组合短期效应组合内力值结果见表1.6，弯矩图和剪力图如图1.15、图1.16所示表1.6短期效应组合内力值单元位置弯矩M（KN•m）剪力Q（KN）MmaxMminQmaxQmin1112133456979891091181241.45E+04-3.12E+04-7.79E+05-7.53E+041.19E+05-4.78E+05-1.29E+051.08E+04-2.94E+054.39E+032.25E+04-1.01E+031.69E+045.44E+04-2.21E+04-2.78E+034.96E+04-1.68E+04-3.39E+023.74E+04-7.54E+031.85E+031.23E+04-9.02E+04-8.63E+05-1.08E+058.05E+04-5.48E+05-1.76E+05-3.02E+04-3.50E+05-2.92E+041.88E+04-3.40