基于3D卷积神经网络的高铁轨道质量指数预测方法

轨道质量指数（TQI，Track Quality Index）是反映高铁整体线路质量状态的重要指标，分析TQI数据的变化规律能够对高铁线路养护维修提供重要指导和参考依据。为提高TQI数据预测的准确性，提出了一种多项特征数据的3D卷积神经网络模型，分析了TQI数据特征，抽取时间、空间、检测项数据并形成三维特征数据集，基于3D卷积神经网络算法，构建8层TQI预测模型，并从初始化参数、学习速率、激活函数、损失函数、Dropout方法等角度对模型进行优化，并利用某高铁线检测数据进行试验验证。结果表明，3D卷积神经网络模型可较好的预测高铁线路状态变化趋势，且对比于BP神经网络和2D卷积神经网络方法，平均绝对误差分别降低了41.48%、26.32%，均方差分别降低了65.42%、39.93%，证明了该方法的准确性与有效性，对于预测TQI与制定高铁线路养护维修计划具有实用价值。

High–speed railway track quality index prediction method based on 3D convolution neural network

Track Quality Index(TQI) is an important indicator reflecting the overall quality status of the high-speed railway, thus the analysis of the change pattern of TQI data can provide important guidance and reference for the maintenance and repair of high-speed railway. This paper proposed a 3D convolutional neural network model with multiple feature data, analyzed the characteristics of TQI data, extracting time, space and detection items to form a three-dimensional feature data set. Based on 3D convolution neural network algorithm, the paper constructed an 8-layer TQI prediction model, and optimized the model from the aspects of initialization parameters, learning rate, activation function, loss function, Dropout method, and used the detection data of a high-speed railway line for experimental verification. The test results show that the 3D convolution neural network model can better predict the state change trend of high-speed railway lines. Compared with BP neural network and 2D convolution neural network, the average absolute error is reduced by 41.48% and 26.32%, and the mean square error is reduced by 65.42% and 39.93%, respectively. It is proved that the method is accurate and effective, and has practical value for predicting TQI and formulating maintenance plan of high-speed railway lines.