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Objective: In order to improve efficiency of road survey and save manpower and material resources, this paper intends to apply Google Earth to the feasibility study stage of road survey and design. Limited by the problem that Google Earth elevation data lacks precision, this paper is focused on finding several different fitting or difference methods to improve the data precision, in order to make every effort to meet the accuracy requirements of road survey and design specifications. Method: On the basis of elevation difference of limited public points, any elevation difference of the other points can be fitted or interpolated. Thus, the precise elevation can be obtained by subtracting elevation difference from the Google Earth data. Quadratic polynomial surface fitting method, cubic polynomial surface fitting method, V4 interpolation method in MATLAB and neural network method are used in this paper to process elevation data of Google Earth. And internal conformity, external conformity and cross correlation coefficient are used as evaluation indexes to evaluate the data processing effect. Results: There is no fitting difference at the fitting point while using V4 interpolation method. Its external conformity is the largest and the effect of accuracy improvement is the worst, so V4 interpolation method is ruled out. The internal and external conformity of the cubic polynomial surface fitting method both are better than those of the quadratic polynomial surface fitting method. The neural network method has a similar fitting effect with the cubic polynomial surface fitting method, but its fitting effect is better in the case of a higher elevation difference. Because the neural network method is an unmanageable fitting model, the cubic polynomial surface fitting method should be mainly used and the neural network method can be used as the auxiliary method in the case of higher elevation difference. Conclusions: Cubic polynomial surface fitting method can obviously improve data precision of Google Earth. The error of data in hilly terrain areas meets the requirement of specifications after precision improvement and it can be used in feasibility study stage of road survey and design. [ABSTRACT FROM AUTHOR]

Waste engine oil (WEO) as a rejuvenating agent is used to restore aged asphalt of different aging degree and the effect of WEO on the reclaimed properties is investigated. The results indicate that WEO can make the properties of aged asphalt restore. The mixing amount of WEO increases with the aging degree. For the asphalt sample which aged for 5h, 2% of mixing amount can make the penetration, softening point, ductility of aged asphalt restore. For the asphalt sample which aged for 7.5h and 10h, 4% of mixing amount can make the penetration, softening point, ductility of aged asphalt restore. Compared with original asphalt, the construction temperature of regenerating asphalt increase slightly. Adhesion ability between aggregate and asphalt is affected by WEO and anti-stripping materials are expected to be used. [ABSTRACT FROM AUTHOR]