文献类型：期刊文献

英文题名：Influence of the main controlling factors on the tangential restitution coefficient of rockfall impact

作者：Ji, Zhong-Min[1,2,3];Wang, Ting-Hui[1];Wu, Jie[4];Wu, Fa-Quan[3];Li, Zhen-Hua[5];Wang, Dong-Po[2];Tang, Yi-Ju[6];Zhao, Chang-Le[1];Niu, Qing-He[7]

机构：[1]Henan Polytech Univ, Sch Civil Engn, Jiaozuo 454003, Peoples R China;[2]Chengdu Univ Technol, State Key Lab Geohazard Prevent & Geoenvironm Prot, Chengdu 610059, Peoples R China;[3]Shaoxing Univ, Sch Civil Engn, Shaoxing 312000, Peoples R China;[4]Zhe Jiang Rock Innovat Co Ltd, Shaoxing 312000, Peoples R China;[5]Henan Polytech Univ, Sch Energy Sci & Engn, Jiaozuo 454003, Peoples R China;[6]Henan Univ Urban Construct, Coll Municipal & Environm Engn, Pingdingshan 467036, Peoples R China;[7]Shijiazhuang Tiedao Univ, Sch Civil Engn, Shijiazhuang 050043, Peoples R China

年份：2025

卷号：345

外文期刊名：ENGINEERING GEOLOGY

收录：SCI-EXPANDED(收录号：WOS:001394636100001)、、EI(收录号：20245217586288)、Scopus(收录号：2-s2.0-85212845043)、WOS

基金：This study was financially supported by the National Natural Science Foundation of China (Grant No. U2244228; Grant No. 42307250) , Opening Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Chengdu University of Technology) (Grant No. SKLGP2023K007) , Natural Science Foundation of Henan (Grant No. 222300420366) , and the China Postdoctoral Science Foundation (Grant No. 2022M721033) .

语种：英文

外文关键词：Rockfall; Impact-rebound process; Tangential restitution coefficient; Main controlling factors; All working conditions

外文摘要：The tangential restitution coefficient (Rt) is a key control parameter for predicting rockfall impact-rebound processes. However, as the understanding of this parameter is not yet profound or comprehensive, it has received less attention, and there is no consensus on the existing research conclusions regarding it. Therefore, in this study, eight main controlling factors of R t were identified according to the impact dynamics theory and the results of previous studies. Subsequently, the effect of each main controlling factor on R t was systematically investigated using a specially developed test apparatus. The incident velocity (V) positively correlated with R t ; however, when V was sufficiently large, its effect on R t was insignificant. Based on the slopes of the loose superficial materials, the two were negatively correlated. For vertical impacts on an inclined slope (VI), R t decreased with an increase in the impact angle, whereas, for inclined impacts on the horizontal ground (IH), the impact angle had the contrary effect on R t for blocks prone to local fragmentation. To clarify the effect of rotational speed on R t , two integrated variables, the normal and tangential impact posture coefficients ( IPC y and IPCx) which comprehensively consider the rotational speed, block shape, and impact posture, were introduced and the contact characteristics of the block and slope were classified and explored. When the mass centre (MC) of the block was in front of the contact point (CP), IPCy was positively correlated with Rt, whereas, the relationship between the two was unclear when the MC was behind the CP. Generally, R t values were higher under the former condition than that under the latter, and the effects of gravity and local contact crushing of the angular-shaped blocks on R t were more significant than that of IPCx under VI. On densely rocky and loosely material slopes, R t showed upward and downward trends, respectively, as the block size increased. The higher the angularity and geometric asymmetry of the block, the higher was the R t value. Under low- or high-kinetic-energy conditions, R t increased or decreased with increasing Schmidt hardness of the block. Considering all the slope materials, R t increased with an increase in Schmidt hardness. A new index, effective impact surface roughness, was introduced to quantify the roughness level of the slope surface. It exhibited a strong positive correlation with R t for large values, whereas, for small values, R t values displayed polarisation. These findings not only provide a reference for the development of rockfall hazard prediction procedures and the design of related protective structures, but also open new horizons for the subsequent comprehensive understanding and study of the impact motion process.