Experimental investigation on near‐field edge wave run‐ups generated by landslides in narrow reservoirs

• Published in: Geological journal (Chichester, England) England), 2023-06, Vol.58 (6), p.2268-2282
• Main Authors: Liu, Jizhixian, Wang, Yang, Xiao, Ting, Yin, Kunlong, Huo, Zhitao, Wang, Xing, Tang, Yang
• Format: Article
• Language: English
• Subjects: Coastal structures; Decay; edge wave; Edge waves; Empirical equations; Hazard assessment; Hazard mitigation; Laboratory experimentation; laboratory experiments; Landslides; maximum wave run‐up; Mitigation; narrow reservoir; Near fields; Offshore structures; Port facilities; Reservoirs; subaerial landslide‐tsunamis
• ISSN: 0072-1050; 1099-1034
• DOI: 10.1002/gj.4674

Edge waves generated by subaerial landslide‐tsunamis (SLTs) often have potentially huge amplitudes that can endanger human lives, offshore structures, coastal cities and port facilities around reservoirs. Maximum edge wave run‐up (RuM) is the most important parameter for SLT hazard mitigation in an engineering context. This study aimed to investigate the effects of the hill slope angle α on RuM, the first edge wave run‐up Ru1 and the first edge wave decay in the near field Ru1(r/h) through 84 laboratory experiments, which were conducted in a three‐dimensional river channel with α values varying from 15° to 40°. For smaller α values, we found that RuM increased with the increase in α while for large α values exceeding 30°, RuM decreased with the increase in α. An empirical equation considering the effect of α was proposed for the prediction of RuM in the near field, which was well verified by a real case. Additionally, the first edge wave run‐up decay along the shore is also discussed in this paper. This work could have some favourable implications for the preliminary hazard assessment of SLTs. Subaerial landslide‐tsunamis pose a catastrophic natural hazard in narrow reservoirs. The generation and propagation of edge waves and the effect of the hillslope ramp angle (α) on edge wave run‐up (Ru) are investigated with 84 experiments. An empirical equation for a quick estimation of Ru was driven.