Analyzing The Settlement Influence Factors And Calculation On Soft Groud Of The Expressway

Basing on the status that the designed settlement number doesn't match the fact on soft groud of Xu-Su expressway during the observation, basing on the status that the settlement number of one observation point is fluctuating during the period of measure,enclosing the core problem of settlement calculation and prediction on soft groud,this paper has launched research in several following respects:(1) Explaining mechanism of settlement of the roadbed, the paper has analysed traditional calculation method about settlement of roadbed including e~lgp curve method and e~p curve method that always brings some error to the grosses of settlement of roadbed when calculating.(2) Refersing to the two-dimension Biot concretion theory that consider horizontal pervasion,the paper has used two-dimension finite element method to calculate the settlement of the roadbed of expressway. The two-dimension finite element method can consider that lateral distortion work on the settlement, also can simulate the process of construction and load. By some cases the finite element method has improvement at calculating precision by a long way, and it is a kind of comparatively perfect method.(3) The paper has compared the number of settlement that has separately been calculated by the traditional method and the finite element method. In this way we can mend the revision coefficient and improve its precision of calculation when using the traditional method.(4) The three-axles always hasn t been done to test the parameter in general road engineering and we need to calculate the settlement by the finite element method.So this paper has studied the parameter inversion analysis by way of combining the approximate calculation with modified complex form optimization when we calculate the settlement by the finite element method which not only can solve the problem that the parameter is difficult to be fixed to a certain extent but also reduce the work load about calculating.(5)As to use various kinds of curves to predicte the settlement of the roadbed ofexpressway , there are their own suitability . Radial basis function neural network method has more obvious advantage than various kinds of curves method of predicting the settlement of the roadbed of Xu-Su expressway that has been introduced by this paper,with its strong fault-tolerant, a good ability of studying by oneself, self-adaptation and organizing by oneself.(6)Basing on a large number of materials of settlement on soft groud,this paper has qualitatively analysed various kinds of factors influencing the settlement on soft groud. Therefore, it is easy to understand the possibility of fluctuating with time of settlement number on soft groud.