- ItemNumerical Modelling of Slope Instability(Elsevier, 2015-11-07) Chalmovský, JurajThis article is dealing with stability of the highway cut in Eastern Slovakia. The cut is situated in rock environment of the Carpathian flysch, which in area of the cut mostly consists of shale with different degree of weathering. The cut is supported by an anchored pile wall. Rock environment is changing from the surface to the depth from alluvium clays, sands and completely weathered shale to fresh shale. The potential slip surface was investigated after evaluation of data from geotechnical monitoring, so stability of the pile wall has to be analyzed. Finite element analysis was done and two material models were compared to results of geotechnical monitoring. Deformation analysis and the safety factor are discussed. Two models were compared in these terms: Mohr - Coulomb material model and jointed rock material model. These models are introduced because of shale anisotropy and simplification of behavior model via jointed rock model. Jointed rock model was introduced as an anisotropic model and required geotechnical parameters for calculations are discussed in comparison with the Mohr – Coulomb material model. Anisotropic behavior of shale will be discussed and analyzed. Short recommendations for the use of these models are presented in the paper.
- ItemA nondestructive indirect approach to long-term wood moisture monitoring based on electrical methods(MDPI, 2019-07-24) Slávik, Richard; Čekon, Miroslav; Štefaňák, JanWood has a long tradition of use as a building material due its properties and availability. However, it is very sensitive to moisture. Wood components of building structures basically require a certain level of moisture protection, and thus moisture monitoring to ensure the serviceability of such components during their whole lifespan while integrated within buildings is relevant to this area. The aim of this study is to investigate two moisture monitoring techniques promoting moisture safety in wood-based buildings (i.e. new structures as well as renovated and protected buildings). The study is focused on the comparison of two electrical methods that can be employed for the nondestructive moisture monitoring of wood components integrated in the structures of buildings. The main principle of the two presented methods of the moisture measurement by electric resistance is based on a simple resistor–capacitor (RC) circuit system improved with ICM7555 chip and integrator circuit using TLC71 amplifier. The RC-circuit is easier to implement thanks to the digital signals of the used chip, whilst the newly presented integration method allows faster measurement at lower moisture contents. A comparative experimental campaign utilizing spruce wood samples is conducted in this relation. Based on the results obtained, both methods can be successfully applied to wood components in buildings for moisture contents above 8%.