STUDY ON EVALUATION METHODS FOR THE DESIGN OF OVERHEAD STRUCTURES IN URBAN AREAS AIDED BY THE COMPUTER GRAPHICS SIMULATION

本计画之目的为发展都市高架、高架道路、车站广场行人平台等之设计评估方法，并以电脑绘图模拟为辅助，第一年改良电脑绘图软体以模拟高架结构，特别是改善结构三维形状资料输入之效率。利用该系统进行了两类分析：第一，分析了高架公路钢筋混凝土桥墩的尺寸因素对其景观的影响;从压力感和稳定性的角度来看，景观的要素是建筑面积比和净空高度。评价意义在该指标的40%~ 50%之间变化。其次，分析了视点变化对车站广场步行平台景观评价的影响。行人平台的备选方案的图像是通过视点的移动而改变的。例如，随着甲板高度的增加，结构的压力感总体上有所降低，但从远观上看并不明显。第二年，开发了计算机图形动画系统。通过对人行道景观设计的评价试验，对动画和静态表现方法进行了比较。它是明确的，动画是适当的心理压力感的评价，由于对物体的形状和体积的感知，但对于评价，如风景如画的美感，它几乎没有优势。

The aim of this project is to develop the evaluation methods for the design of overhead structures in urban areas; elevated highways, pedestrian decks at station plaza and so on, aided by the computer graphics simulation.In the first year, software of computer graphics was improved for the simulation of overhead structures, especially, in order to improve efficiency of data entering of three dimensional shapes of structures. By employing this system, two type of analysis are carried out.First, the effects of dimension factors of RC-pier of elevated highways upon their landscape are analyzed. From the viewpoint of sense of pressure and stability, the essential factor of landscape is the area ratio of structure and overhead clearance. The evaluation sense is changeable between 40% and 50% of this index.Second, the effects of change of eye point upon the landscape evaluation of the pedestrian decks at station plaza are analyzed. The image of alternative plans of pedestrian decks are changeable by the movement of eye point. For example, the sense of pressure of structures is decreased in general when the height of decks are increased, but it is not clear on the distance view.In the second year, animation system of computer graphics is developed. The animation and the still presentation methods are compared by evaluation tests of landscape design of pedestrian decks. It is cleared that the animation is appropriate for the evaluation of psychological sense of pressure due to the perception of shapes and volumes of objects, but is has little advantage for evaluation of such as sense of picturesque beauty.