混凝土箱梁悬臂板计算方法

Calculation method for cantilever slab of concrete box girder

针对目前混凝土箱梁悬臂板计算的不合理性,以有限元为基础,结合诸多算法,应用子模型技术分析了箱梁畸变、悬臂板长度及坡度、荷载作用位置等参数对混凝土箱梁悬臂板有效分布宽度的影响规律。在此基础上,依据最小二乘法原理,利用Matlab分布拟合得到混凝土箱梁跨中悬臂板有效分布宽度的实用计算公式。结果表明:畸变大,有效分布宽度增大;悬臂板长度和坡度与有效分布宽度变化趋势相同,呈曲线关系;荷载作用点靠近悬臂板根部,有效分布宽度变小。相对于其他算法,有效分布宽度实用计算公式所得结果接近试验数据。

Aimed at the unreasonable calculation methods for cantilever slabs of concrete box girders, based on FEM and some kinds of calculation methods, a analyses is performed by submodel technique to study the influence of several parameters, such as distortion for box girders, length and degree of slope for cantilever slabs as well as load location. Based on the simulation results, according to least-square procedure, the effective distribution width formula for cantilever slabs of middle-span of concrete box girders is proposed by Matlab. Test results indicate that： the effective distribution become wide with the increment of distortion; the length and degree of slope for cantilever slabs keep identical curve tendency with the effective distribution width; the effective distribution width decrease while the load location approach to cantilever slab roots; compared to other algorithms, the result of calculation formulas presented is approximate to test one. 7 tabs, 4 figs, 10 refs.