Gray Theory In Highway Fill In The Application Of Quality Control In The Roadbed

Subgrade is the important part of the highway engineering and the base of the pavement. The stability of subgrade is very important for the quality of pavement engineering; it affects the valid use of highway. With the rapid development of the high-grade highway of our country, high fill or soft ground will often turn up, so we have analyzed the disease and the reason of the subgrade, and from the design, construction two aspects to begin, to discuss the control of embankment quality effective action and pay attention to the important points.The subgrade which is very tall or built on soft foundation often turns up descent, it will cause the deformation of pavement and affect the safety of cars. The traditional calculating method and FEM need to do the corresponding experiment and receive many affect factor, causes the predicted and the actual difference is big. The commonly used hyperbola long-base method and the index tune long-base method is only suitable after the dead load,also has the long-term observation material the subgrade analysis, the hyperbolic curveforecast result is generally big, the index tune curve measured the result is generally small. In order to solve these problems, and tack into account "grey phenomena", this thesis puts forward a dynamic monitoring method of embankment's descent based on grey theory, and build a GM(1,1) predicting model . The thesis adjusts the model to be more adaptable and better effectiveness in predicting by setting up unequal interval direct GM(1,1) model and metabolism predicting model. It's very important to ascertain the time of the next process, and it also can raise the efficiency of highway engineering. This thesis gives the way to resolve the exceed descent by using of the predicting of embankment's descent. In the actual construction, often needed after the upper level of earth fills settlement observation material estimate next level of earth fills roadbed subsidence, this article according to the subgrade subsidence rule to construct in the subgrade earth fill process predicting model. According to the grey theory forecast result and the project reality, the reasonable determination flip-height in advance to command construction.