Department of Applied Rock Mechanics

The Department of Applied Rock Mechanics studies rocks and their short- and long-term changes depending on endogenous and exogenous factors. This includes monitoring and analysis of rock masses depending on rock composition and its properties, precipitation or temperature. In addition to direct monitoring in natural conditions, it uses a fully equipped rock mechanics laboratory, which allows the investigation of rocks' basic and advanced physical and mechanical properties.

International Cooperation

University of Bayreuth
www.geomorph.uni-bayreuth.de/en/team/sass/index.php
Germany

Prof. Oliver Sass

Yosemite National Park
https://www.nps.gov/yose/
USA

Dr. Greg Stock

U.S. Geological Survey
https://www.usgs.gov/
USA

Landslide Hazards Program, Dr. Brian Collins

University of Milan / Universitá degli Studi di Milano
www.unimi.it/en/ugov/person/corrado-camera
Italy

Dr. Corrado Camera

Istanbul Technical University, Eurasia Institute of Earth Sciences
https://eies.itu.edu.tr/en
Turkey

Prof. Tolga Görüm

 

University of Utrecht
www.uu.nl/staff/DDraebing
Netherlands

Dr. Daniel Draebing

Instituto Geografico Nacional de España, Santa Cruz de Tenerife
www.ign.es
Spain

Dr. Stavros Meletlidis

GNS Science, Wellington
www.gns.cri.nz
New Zealand/Aotearoa

Dr. Sam McColl

Results

Observation of the rock slope thermal regime, coupled with crackmeter stability monitoring: initial results from three different sites in Czechia (central Europe)

2021

Článek popisuje univerzální, modulární a finančně dostupný systém monitoringu skalního svahu. Pomocí tohoto systému, je možné in-situ pozorovat klimatické proměnné, teplotu v povrchové vrstvě skalního svahu až do hloubky 3 m a dynamiku vybraných diskontinuit v čase. První výsledky ukazují na rozdíly pozorované mezi jednotlivými lokalitami. Pro budoucí rozsáhlejší statistickou analýzu dat, budou použity delší časové řady. Dále budou data využita pro analýzu dlouhodobých trendů a numerické termomechanické modelování.

Racek, O., Blahůt, J., and Hartvich, F. (2021): Observation of the rock slope thermal regime, coupled with crackmeter stability monitoring: initial results from three different sites in Czechia (central Europe), Geosci. Instrum. Method. Data Syst., 10, 203–218, 
DOI: 10.5194/gi-10-203-2021

Snímek zachycuje tři osazené lokality skalního svahu. Jednotlivé monitorované bloky jsou označené přerušovanou čarou s rozdílnou barvou.
Dále je vyznačena poloha meteostanice a teplotního čidla ve vrtu.


 

New Insights into the Internal Structures and Geotechnical Rock Properties of the Giant San Andrés Landslide, El Hierro Island, Spain

2023

Klimeš, J.; Hussain, Y.; Mreyen, A.-S.; Cauchie, L.; Schlögel, R.; Piroton, V.; Petružálek, M.; Blahůt, J.; René, M.; Meletlidis, S.; Havenith, H.-B. (2023) New Insights into the Internal Structures and Geotechnical Rock Properties of the Giant San Andrés Landslide, El Hierro Island, Spain. Remote Sens., 15, 1627. https://doi.org/10.3390/rs15061627

Rate-dependency of residual shear strength of soils: implications for landslide evolution

2023

Duque, J., Loche, M., & Scaringi, G. (2023). Rate-dependency of residual shear strength of soils: implications for landslide evolution. Géotechnique Letters, 13(2),1-8. https://doi.org/10.1680/jgele.23.00004
 

Rock Surface Strain In Situ Monitoring Affected by Temperature Changes at the Požáry Field Lab (Czechia)

2023

Racek O., Balek J., Loche M., Vích D., Blahůt J. (2023) Rock Surface Strain In Situ Monitoring Affected by Temperature Changes at the Požáry Field Lab (Czechia). Sensors 23(4), 2237. https://doi.org/10.3390/s23042237
 

Services

Core drilling of rocks

Core drilling of rocks
Core rock drilling up to 250 mm in diameter and up to 3 m deep Husqvarna DMS 240 Ondřej Racek

Analysis of rock samples


Determination of basic rock characteristics
Specific and bulk density, moisture content, . absorption, porosity, permeability   Jan Blahůt 
Ultrasonic measurements of rock samples
P and S waves velocities measurement, determination of dynamic elastic moduli at atmospheric pressure or during uniaxial loading Vallen Acoustic Emission System Jan Blahůt 
Determination of elastic rock properties
Dynamic and static moduli (Young, shear, and bulk moduli, Poisson number)   Jan Blahůt 
Rock strength measurement
Uniaxial Compressive Strength, Tensile strength, Shear strength, Triaxial testing MTS 815 Jan Blahůt 

Infrared thermography measurements

Infrared thermography measurements
Single or repeated measurements FLIR E95 Ondřej Racek

Climatic chamber

Climatic chamber
Chamber with temperature (-42°C to 190°C) and humidity (RH 10%-98%) settings Climate chamber CTC 256 Memmert Ondřej Racek

Geotechnical / Geological monitoring of rock masses

Geotechnical / Geological monitoring of rock masses
Dilatometric measurement (accuracy up to 0.01 mm) HOLLE  Dilatometr  Jan Blahůt
Crack measurement (accuracy up to 0.01 mm) Gefran crackmeter

Experimental laboratory of rock properties in the former Požáry quarry (Prosečnice)

Experimentální laboratoř vlastností skalních hornin v bývalém lomu Požáry (Prosečnice)

Experimental measurements of changes in rock properties in natural conditions are conducted in a field laboratory located in the former granodiorite quarry Požáry near Prosečnice in Central Bohemia. The monitored variables, and instruments, include:

  • Climatic monitoring (precipitation, temperature, humidity and air pressure, wind direction and speed)
  • Incoming and reflected radiation (pyranometers)
  • Crack movement (induction and VW crack meters)
  • Surface tension (film strain gauges)
  • Rock mass moisture (apparent dielectric permittivity/capacity method)
  • Rock mass temperature measured (thermocouples up to 3 m depth)
  • Surface thermal properties (IR cameras)
  • Apparent resistivities within the rock mass (electrical resistivity tomography - ERT)

Our ongoing research focuses on examining the impact of temperature on alterations in rock mass properties, specifically changes in stress and strain, influence of thermal shock and temperature distribution on the surface and within the rock mass. Additionally, we study the rate and distribution of moisture on both the surface and within the rock mass.

Team:
Mgr. Jan Blahůt, Ph.D.
Mgr. Ondřej Racek
MSc. Marco Loche, Ph.D. 

Cooperation: Statotest, U Jezu 525/4, 460 01 Liberec, Czechia https://statotest.com/ 


Publications:

  • Racek O, Balek J, Loche M, Vích D, Blahůt J (2023) Rock Surface Strain In Situ Monitoring Affected by Temperature Changes at the Požáry Field Lab (Czechia). Sensors 23(4): 2237. https://doi.org/10.3390/s23042237
  • Racek O, Blahůt J, Hartvich F (2021) Observation of the rock slope thermal regime, coupled with crackmeter stability monitoring: initial results from three different sites in Czechia (Central Europe). Geoscientific Instrumentation, Methods and Data Systems, 10: 203-218. https://doi.org/10.5194/gi-10-203-2021
  • Loche M, Scaringi G, Blahůt J, Melis MT, Funedda A, Da Pelo S, Erbì I, Deiana G, Meloni MA, Cocco F (2021) An infrared thermography approach to evaluate the strength of a rock cliff. Remote Sensing 13(7): 1265. https://doi.org/10.3390/rs13071265 

Laboratory of Rock Mechanics

Laboratoř mechaniky hornin

The laboratory deals with determining the physical and mechanical properties of rocks. This includes assessing bulk and specific density, porosity, permeability, and strength through various tests such as unconfined compression test (UCS), tensile strength test (Brazilian test), fracture toughness test, triaxial test, and shear strength test. Additionally, we determine the static and dynamic moduli of rocks and measure the anisotropy of rocks under different pressures. These evaluations are conducted using the instruments listed in the "services" section.

Team:
Dr. Xuan-Xinh Nguyen, Ph.D.
Ing. Tomáš Lokajíček, CSc.
BSc. Artëm Polezhaev
MSc. Ghazaal Rastjoo

Booking can be made by contacting the responsible person at the laboratory.