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1、,Highway Location,Outline,1、The definition and basic principle of Highway Location 2、The highway location process 3、Impacts of Highway Construction on the Environment and Economic 4、The methods of highway location 5、Conclusions,1、Definition: Its a process that within the scope of “roadband”(or calle
2、d alignment corridor)selected in the line selecting layout stage, according to the settled technical standards, combining the datailed topography, geology and other natural conditions and considering the reasonable arrangements of the flat, vertical and horizontal sides, the engineer set the exact l
3、ocation of the center line of road.,1、Principle: Roadway elements such as curvature and grade must blend with each other to produce a system that provides for the easy flow of traffic at the design capacity,while meeting design criteria and safety standards.,2、The highway location process,(1)Office
4、study of exsiting information (2)Reconnaissance survey (3)Preliminary locate survey (4)Final location survey,（1）The first phase of Highway Location(Office study of exsiting information),A、Definition B、The sources of the data C、The types of the data D、The preliminary analysis of the data,（2）Reconnais
5、sance survey,The object of this phase is to identy several feasible routes,each within a band of a limited width of a few hunderd feet. 插图,Feasible routes are inentified by a stereosopic examination of the aerial photographs.,Control points between the two endpoints are determined for each feasible
6、route.,（3）Preliminary location survey,Establishing all the control points; Determing preliminary vertical and horizontal alignments.,Preliminary alignments are used to evalute the economic and environmental feasibility of the alternative routes.,（4）Final Location Survey,A、Determining the horozontal
7、and vertical alignments. B、Locating the positions of structures and drainage channels.,Tools,A、Splines B、Curve templates,3、Impacts of Highway Construction on the Environment and Economic,A、Environment B、Economic,4、The methods of highway location,A、Paper location B、Site location C、Aerial survey location,5、Conclusions,