郑武客专线粉质土地基沉降观测数据异常值判别及沉降预测研究

Discrimination of Abnormal Observation Data and Settlement Prediction for the Silty Soil Subgrade of Zhengzhou-Wuhan Passenger Dedicated Line

郑武客专沿线广泛分布有深厚的粉质土,客运专线对工后沉降控制非常严格,根据沉降监测数据控制填土速率,保证路堤在施工中的安全与稳定,预测工后沉降确定无渣轨道的施工期,控制工后沉降在设计允许范围之内是路堤填筑的关键。对路基沉降观测数据的可靠性、沉降数据的预处理以及沉降观测异常数据判别方法进行了系统的叙述,尝试用最小二乘支持向量机对沉降数据进行预处理;讨论了各种预测模型的特点及适用性。基于沉降资料可靠性和沉降预测方法两方面的研究,形成了粉质土地基沉降系统预测方法,并通过实例详细介绍了预测过程。预测结果显示郑武粉质土地基沉降已基本趋于稳定,运行期不会发生较大的工后沉降,郑武客专地基处理及施工方法是成功的。

Since thick silty soil distributes widely along the Zhengzhou-Wuhan Passenger Railway, the post-con- struction settlements should be controlled strictly. The key to embankment filling are regarded as： the control over filling speed based on the settlement observation data to ensure the embankment stability ; the prediction of post-construction settlements to determine the period of ballastless track construction ; and the control over settlements af- ter construction to the allowable limit. The reliability and pre-processing of settlement data, and the method of dis- criminating abnormal settlement data are presented in this paper. The characteristics and applicability of settlement prediction models are discussed. The LSSVM （least squares support vector machine） is used in the pre-processing of settlement data. Hence a systematic prediction model for silty soil is established. The detailed prediction process is expounded by giving examples, and the prediction results show that the settlement tends to be stable; no large post-construction settlement would occur during the operation period, which suggest that the foundation treatment and construction method is successful.