Hunan Province Highway Subgrade Settlement Prediction Methods

Settlement of roadbed has become difficult technical problem in operation and construction of higher way. Once uneven settlement or big settlement does happen, it will cause great losses. Therefore it is of great significance to make study on settlement of highway.This paper is based on the soft soil and red stone roadbed of Hunan Highway, from which a few typical sections are selected for settlement monitoring. After meticulous investigation in situ, and a great number of indoor tests, analyzed with FEM method is the settlement of red stone roadbed after its filling. Detailed investigation of construction filling and settlement after construction and some major conclusions are made as follows:1. Systematically analyzed are the settlement mechanism of soft soil roadbed and soil and rock roadbed, and generalized are the settlement calculation methods. Much emphasizes are made on the compacting mechanism and other impact factors of soil and rock roadbed2. A variety of optimization and comparison of method of predicting roadbed settlement are attempted to find most appropriate method3. Based on indoors tests, slaking properties and physical properties slaking substance are analyzed to further discuss the settlement mechanism of red sandstone roadbed.4. A simple and practical predict method are put forward. At the same time applied is Plaxis FEM software. After comparing these two methods, empirical data of settlement after construction are brought out.