Study On Settlement And Deformation Of Soft Soil Subgrade In Tangcao Railway

With the strategic layout of China's economic construction in full swing,the construction of transportation hub has entered another peak period.The strategic deployment for docking "The Belt and Road" and "maritime Silk Road",the railway construction to sea will inevitably encounter the problem of coastal soft soil.Because of its own characteristics,soft soil foundation is prone to cause settlement and deformation in practical engineering.In this paper,taking the base section of the soft soil road of the Tang Cao railway as the research object,the law of consolidation and settlement in the construction process of the soft soil subgrade in this area is studied by means of field monitoring,theoretical analysis and numerical simulation.The research status of soft soil subgrade at home and abroad and the comprehensive control technology of settlement are summarized.On this basis,based on the construction of the new Tangshan to Caofeidian railway project,the settlement monitoring is carried out in the test section,the measured data are analyzed,the settlement law is obtained,and the hyperbolic method and the three point method are used to predict the settlement.In this paper,the finite element software PLAXIS is used to analyze the soft soil subgrade of the test section,and Mohr-Coulomb Model and Soft-Soil-Creep Model which can react to the soil time effect are used in the calculation of the silt,silt and silty clay and the silt clay.At the same time,sensitivity analysis is made for the influence factors of partial settlement of soft roadbed treated by vacuum preloading method.The results show that the two constitutive models can reflect the settlement law and characteristics of soft soil subgrade to a certain extent,but the calculated settlement value of Mohr-Coulomb Model is smaller,the settlement value of Soft-Soil-Creep Model is more consistent with the measured value,and the difference of the two is about 14.5%.It is shown that drainage consolidation and creep occur simultaneously in the deformation process of soft soil.It is necessary to consider the characteristics of creep consolidation when analyzing soft soil subgrade.In this paper,the settlement characteristics and treatment methods of the soft soil subgrade of the Tang Cao railway are studied in detail,and the conclusion applicable to the research object can be obtained,which can provide some reference for the construction ofsimilar projects.