Research on Restitution Coefficients of Rockfall

• Main Authors: Chen, Yuyun, 陳俞云
• Other Authors: Chen, Shiou
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/96768655025804447752

碩士 === 華梵大學 === 環境與防災設計學系碩士班 === 101 === Mitigation of landslides and rockfall is an important issue in , Taiwan which located at the circum-Pacific seismic belt, Occasionally it encounters extremely torrential rain falling in a short period of time induces erosion of slope coming with disasters of rockfall and severe debris flow. The coefficient of restitution of rockfall is a very important input data for the numerical simulation. In this study, the approach to determine the coefficient of restitution is conducted through the optical measurement and the calculation on the trajectory of rockfall from a height of 100 cm to the slope surface recorded by video. One kind of falling object material (steel balls), two kinds of slope material (concrete, steel) and four slope angles (15°, 30°, 45° and 60°) are used as the controlled factors to observe the variation of restitution coefficient. It is found from the results that Rn , Rv , and RE increase with respect to the increment of slope angle, while Rt increases when slope angle decreases. As for the simulation using DDA, φ and Kn are major parameters that control the results. Most of the coefficient of restitution RE for all kind of material may be made by triggering φ and Kn.