Number of the records: 1
Measurements and modeling of the post-failure micro-deformations and tilts of the Preonzo unstable slope, Alpe di Roscioro, Switzerland
- 1.
SYSNO ASEP 0542058 Document Type J - Journal Article R&D Document Type Journal Article Subsidiary J Článek ve WOS Title Measurements and modeling of the post-failure micro-deformations and tilts of the Preonzo unstable slope, Alpe di Roscioro, Switzerland Author(s) Opršal, Ivo (GFU-E) ORCID, RID
Thun, Johannes (GFU-E) ORCID
Burjánek, Jan (GFU-E) ORCID, RID
Fäh, D. (CH)Article number 105919 Source Title Engineering Geology. - : Elsevier - ISSN 0013-7952
Roč. 280, January (2021)Number of pages 14 s. Publication form Print - P Language eng - English Country NL - Netherlands Keywords rock slope instability ; finite difference modeling ; directional deformations ; micro deformations ; micro tilt ; data mining Subject RIV DC - Siesmology, Volcanology, Earth Structure OECD category Volcanology Method of publishing Open access Institutional support GFU-E - RVO:67985530 UT WOS 000615526300010 EID SCOPUS 85097090130 DOI 10.1016/j.enggeo.2020.105919 Annotation The Alpe di Roscioro, is a site of an unstable rock slope located above the village of Preonzo in southern Switzerland. There have been numerous rock-slope failures with a major event that happened in May 2012. After that event, several seismic stations were set up at the site of the remaining highly fractured and unstable rock mass. The analysis of continuous seismic recordings has shown a high number of permanent micro-deformations and tilts, recorded by a seismometer located on top of the unstable part of the slope. In terms of the ground motion, the directions of these disturbances are parallel to the mean strike of the mapped fracture network, implying a connection to the ongoing deformations of the rock mass. The static deformation field of the fractured rock mass is modeled by finite-difference method (FD). The FD method enables us to apply a reciprocal approach by tilting the affected body of block 1, closest to the stable massif, by measured values and observing the deformations below the seismometer and in the neighboring blocks. The numerical model explains the following features observed in situ: feature 1. The combination of the horizontal displacement and tilt observed approximately at the same measurement point, feature 2. The block 1 center of rotation is shifted towards SSE by similar to 10 m off its center, feature 3. The sensors placed on the stable massif did not record any micro-deformation and tilt signals above the background noise. In the light of the numerical modeling, the weak coupling between the micro-tilt active block 1 and neighboring media explains the absence of detected events in the reference stations placed on the stable massif. The simplified shear and bending force system FD model, indicates that the aftermath of the May 2012 main failure consisted of numerous episodic elementary relaxations of the SSE part of block 1 after the collapse of its NNW compartment, which was previously connected to it. Workplace Geophysical Institute Contact Hana Krejzlíková, kniha@ig.cas.cz, Tel.: 267 103 028 Year of Publishing 2022 Electronic address https://www.sciencedirect.com/science/article/pii/S0013795220318160
Number of the records: 1