Research On The Calculation Method To The Settlement Of Highway's Subgrade

It is a very difficult issue to calculate the settlement of highway's subgrade. There are many methods to calculate the settlement. In this thesis,the calculating methods are classified into the following three:the common calculating method of settlement of highway'subgrade, the calculating method of the process of the settlement of highway'subgrade and the calculating method to the settlement of highway'subgrade based on the in-situ test.The common calculating method of the settlement of highway's subgrade mainly includes layerwise summation method, stress area method, stress path method and the method based on the in situ curve and secant modulu..Their characteristics and shortages have been analyzed respective in this thesis. The calculating method of the process of the settlement of highway'subgrade is to calculate the degree of consolidation with the application of Terzzaghi's consolidation theory, and then calculate the settlement at a certain moment. Currently, the calculation theory on unsaturated soil is not ripe yet. The third calculating method mainly consists of two categories:The first one is establishing the relation of soil elasticparameter and test result via applying in-situ test and probability theory, and then calculate the settlement by the common method. The second one is creating fit curve through the data of precious stage to estimate the latter settlement. The calculation methods to the settlement of composition foundation have been summarized and generalized too in this thesis.Numerical analysis methods have a very quick development in recent years The process of the various calculating methods has been analyzed. Some methods which are apt to be computerization have been programmed by Visual Basic.