Stability Analysis Method For Half Filling And Half Digging Roadbed In Mountain Area

In the construction of highway in mountain area, the types of highway construction site and sub-grades are the first problem need to absolve. The types of highway construction site lie on the physical geography condition and the geological condition of terrane whose basic parameters are fuzzy and uncertainty. Based on the theory of fuzzy mathematic and combined the definitions of the fuzziest and the clearest with the wide-range and the narrow-range, the principle of building subordinate function is given and with the principle, the process of the formation of subordinate function and the substance method is received which is employed to solve the non-uniqueness problems of the conclusions of fuzzy analysis. Based on normal distribution function, fuzzy subordinate function with five terrane geological mechanics parameters and three local physical geography condition parameters is deserved according to this method. Thus the fuzzy classification method of highway in mountain area construction site has been established. The cut and fill sub-grades , a common building model in the construction of highway in mountain area , whose stability decided by the type of cut and fill interface and the physical and mechanical properties of interface. In order to resolve this problem, the interface is divided into five kinds, high-steep interface,common rock-soil interface,soft rock and bad geological interface,unusual soil interface and anomaly shape interface. And the character of each kind interface is pilot studied in this paper. Then the author discus the disadvantages of imbalance the thrust force method which is recommended as a stability analysis method for the cut and fill sub-grades by Specifications for Design of Highway Sub-grades, and through changing grade at the midpoint by increase bars of sliding surfaces to reduce the difference of obliquity between adjacent sliding surfaces, the result of imbalance thrust force method can be improved. Taking the standard section of the cut and fill sub-grades of Huai Xin expressway and the Xupu connection of Shao Huai expressway as example, the author analysis the influences of the mechanics parameters of roadbed filling,the mechanics parameters of interface,the mechanics parameters of sub-grades,the height of filling,the width of filling rode surface,the length of interface,the obliquity of sub-grades to the stability coefficient of the filling roadbed slope with the ameliorate imbalance thrust force method. Finally, the geological condition of terrane and the physical...