基于随机介质的新型铁路路基病害模型

为从大量雷达检测数据中快速识别铁路路基病害类型及位置,自动识别系统的研究成为一种必然.研究目的在于建立自动识别系统研究与测试所需的病害模拟模型.为此引入随机介质模型,构建指数型自相关函数随机扰动的介电常数路基模型,用以表征病害局部范围内介电常数沿各尺度的变化;并分析十余条既有铁路线路的检测数据,得到道碴囊病害及路基下沉病害分布特性,将其融入到随机介质模型之中,得出的结果与现场探挖的结果十分相似.能够反映铁路路基材料的非均匀特性,可以较好的模拟病害内部介质的介电特性.

Study of a New-Type Random-Medium-Based Model for Defects of the Railway Sub-grade

In order to quickly identify the type and the specific position of the defects of the railway sub-grade, the development of an automatic recognition system is becoming more and more necessary. The paper aims at establishing the defects-simulating models necessary for developing and testing the automatic recognition system. Therefore, the random medium models are first introduced in the paper to help build the dielectric constant model of the sub-grade by means of the exponential autocorrelation function with random disturbance, which is used to stand for the variations of dielectric constant within local scope of the defects along the directions. Upon the basis of analyzing the inspection data of more than 10 existing railway lines to get the distributing characteristics of the defects in ballast fouling and the subgrade settlement, which are then integrated into the random medium mod- els to achieve the final results, which are found extremely similar to the those of the field excavation exploration, able to reflect the non-homogeneous characteristics of the materials of the railway sub-grade and better simu- late the dielectric properties of the internal medium of the defects.