Research On Highway Visual Space And In The Application Of Landscape Planning

Highway construction in china is usually considered only "traffic channel" function. Reflection on experiences and lessons of highway construction, the construction concept of "eco-road" began to be seriously in recent years. But the guiding principle of ecological highway construction more likely to static garden landscape, which lack of the consideration of highway users'visual experiences and mental perception, and also goes beyond the roadside natural environment and always cost high. So it is necessary to explore a more scientific and appropriate planning and designing system for highway landscape.High-speed characteristic of landscape aesthetic subjects should be taken into account, highway landscape design is different from garden or even city road design because of its special character of dynamic. People perceive the stimulation of highway landscape at high-speed, and the way that pays more attention at the details or minor scale is unsuitable. In fact, the experiences of highway landscape has "flowing impression" characteristics.During the landscape design research, it should be aware of the driver's visual behavior in different linear characteristics. Focusing point's trajectory of driver in high speed driving should be mastered, on the basis it is found out the driver's attention focused on the regions, it is the so-called visual-space that in the case of high-speed train operation these regions are quickly superimposed to form a strip of space which is different from the road space. Highway landscape planning should be preceded by conducting a detailed site survey and accurately understanding of the relative position and situation of the driver's visual-space and viewpoint in different lines, depending on the spatial composition of landscape element inside visual-space, and then under different viewpoints it is analyzed that the abundance of landscape elements in the visual-space, as the material basis of vantage viewpoint of selection. Such as the vantage viewpoint of the view point in the direction of their field should be completely open, it is cleaned up the direction viewpoint of view barriers. For road information is too little and there's viewpoint site of security risk, by setting a positive way it is necessary of setting visual barriers for active landscape improving, so as to attract to the driver's line of sight within the way. In landscape planning it looks like more scientific that in the appropriate viewpoint site clearance or acquired visual barriers'way as the basis for the degree of planning enclosed space, as well as the basis of engineering and quantitative of highway landscape planning.In the overall experience of the highway landscape rhythm, the emphasis based on the full site survey is the important landscape nodes (vantage point ) and the node selection and division, it should be showed up the landscape function of the vantage viewpoint by the degree of planning enclosed space and carried out the ill-natured viewpoint for landscape improving, and the landscape character design between paragraphs should be enhanced , so as to form the richly varied"flowing impression"of landscape that is fit to occupant psychological pleasure curve.Based on these guidelines, the paper first defines that the landscape is seen by a viewpoint department formed in the mind of the visual impression, it is not the viewing object itself and not related with personal likes and dislikes and education levels. When there is no point of viewpoint, there is no so-called landscape, the same viewing object existing the viewpoint of different aesthetic subjects will result in different preferences. It is pointed out that the road itself is the most important of viewpoint site, and the preparation of the viewpoint site is the focus of highway landscape planning perspective, and the core point of viewpoint site preparation is the treatment of visual barriers in the direction of view. For the good quality of viewing object, all the visual barrier should be removed in the design, so as to make it easier to be seen as viewing objects, and to render it completely in front of the aesthetic subject; for the poor individual quality viewing objects, the visual barrier should be appropriately set by the choice of landscape elements, so as to shield the poor viewing objects in the horizon beyond the aesthetic subject.Due to the servicing core of viewpoint site is depending on the disposition of the visual barrier, it is necessary to understand the driver's characters in the process of visual behavior at high speed and the attention focus area on the different linear features. Based on the theory of dynamic visual, drivers always keep focusing behavior in high-speed driving process , it means drivers remained relatively fixed of the head. Assuming that axis remains the direction when driving the tangent of the track, and equal speed conditions for equal distance gaze. Based on this analysis, the author calculated the drivers'trajectories of attention focus point at straight and curve, and further analyzes drivers'visual behavior at spatial alignment, which looks more in-depth understanding of the drivers in the process of driving the basic situation of visual-space.For more in-depth understanding of the drivers'visual-space, the author used methods of the independent development for drivers'visual-space objective reduction control system, namely "Car Camera Equidistant Automatic Shutter System", it is using for taking pictures of several kinds of typical visual-space. The automatic control system took continually different types of space inside photos which the drivers'attention concentrated, and analysis the proportion of regional conditions which drivers'attention of visual space inside the calculation of the landscape elements constitute. The bow angle of view and curve space which is the first place for the selection of vantage viewpoint. Elevation, empty and small radius curve of visual-space are needed for special conducting as for highway landscape improving.Based on results of the proportion of landscape element inside visual-space and the variation, combination of the selection of vantage viewpoint, the division of the landscape sections and the planning of space surrounded degree, research of appropriate rhythm of the whole experience about highway landscape, namely the formation method of "flowing impression". Analyze technical means of achieve overlooking by the landscape elements selection at different viewpoint site, which form the closed interface, and way of surrounded characteristics planning of main viewpoints site. The introduction of the methods of some special space type of proper landscape, and bring in the open cut tunnel for poor conditioning landscape viewpoint field.