[H-DS05] 地すべりおよび関連現象

[HDS05-14] Accelerating Creep of Landslide Movement and the Rate- and State-dependent Frictional Behavior in It

*Chengrui Chang¹、野田 博之²、王 功輝²、山口 哲生¹ (1.東京大学, 大学院農学生命科学研究科、2.京都大学, 防災研究所)

キーワード：Creep、Rate- and state-dependent friction、Acceleration、The Voight model、Parameter

Landslides show a diverse range of slip behaviors that are similar to tectonic faults. Slow-moving landslides might sometimes accelerate to catastrophic failure. The key motivation of this study is to better characterize the slow-to-fast transition of sheared soil materials as responses to frictional properties. We begin with the lab ring-shear test to simulate accelerating creep behavior in the material and examine its rate- and state-dependent behavior by velocity-step test. We then constrain the accelerating creep by using the Voight model that describes the universal proportionality between velocity and acceleration in the log-log plot for the terminal stage of material failure or natural disasters (Voight, 1988, 1989), especially for landslides. And we obtain frictional parameters by constraining the frictional response of the material in velocity-step tests. It should be emphasized that we focus on the variations of the power exponent α in the Voight model. Finally, we combine the accelerating creep, rate- and state-dependent friction, and theoretical analysis to approach the key issue of the physical base for the Voight model. This study might be useful for studies in landslide mechanics and fault mechanics.

Reference
Voight, B. (1988). A method for prediction of volcanic eruptions. Nature, 332(6160), 125–130.
Voight, B. (1989). A Relation to Describe Rate-Dependent Material Failure. Science, 243(4888), 200–203.