基于TQI与沉降关联性分析的高铁路基服役状态监测

Servicestatus monitoring of high-speed railway subgrade based on correlation analysis of track quality index and settlement

普速铁路常用的有损检测不适用于高铁无砟轨道,目前,高铁路基状态检测多依赖于轨检车无损方法,但轨道质量指数(TQI)仅代表轨道几何状态,无法直接反映路基服役状态且无法判定病害程度。鉴于此,以沪宁城际高铁为对象,采用轨检车检测与工后沉降观测手段,开展高铁路基服役状态监测研究。在绘制全线TQI数据图及工后沉降曲线的基础上,针对TQI与沉降超限做关联性分析,结合地质雷达、波速仪等下部结构探查,提出了“TQI+沉降值+下部扫描”比对筛查的高铁路基服役状态监测方法,并与路基病害工况进行对比验证。结果表明:TQI异常与沉降超限无互相包含关系,且极大值区间互不对应;对比TQI超限次数与幅度,沉降超限与TQI超限次数的相关性更大。相比于侧重TQI评定的传统方法,核减了TQI超限的非病害工况,增加了TQI未超限的病害工况,与高铁现场实际工况更相符。

The commonly used destructive testing of traditional railways ballast track is not suitable for high-speed railway ballast-less track.At present,high-speed railway subgrade status detection mostly depends on the non-destructive method of track inspection car,but the weakness is that the track quality index(TQI)only represents the geometric state of the track,which can t directly reflect the subgrade service status or the severity of the subgrade defects.In view of this,with the Shanghai-Nanjing intercity high-speed railway as the study object,the rail inspection car detection and post-construction settlement observation were conducted to carry out the study on the service status monitoring of high-speed railway subgrade.On the basis of TQI statistical diagram and post-construction settlement curve of the whole line,the correlation analysis of TQI and settlement overruns was carried out,combined with the exploration of under structures such as geo-radar and wave velocity survey,a new service status monitoring method of the high-speed railway subgrade based on the comparison screen of"TQI+settlement value+under-scan"was proposed,while the condition of the subgrade defects was also verified.The results showed that there was no mutual inclusion relation between the overruns of TQI and settlement,and the maximum value didn t correspond to each other.By comparing the frequency and value of TQI overruns,the settlement overruns were more correlated to the frequency.Compared with the previous TQI oriented assessment method,the non-defected conditions with TQI overruns were reduced,and the defected conditions without TQI overruns were increased,which is more consistent with the actual site conditions of high-speed railway.For other in-service high-speed railways which may be greatly affected by the settlement of the soft ground and with a higher proportion of the subgrade,this study can also provide some useful reference for the service status monitoring of them.