1. Influence of mould suction on the volume - change behaviour of compacted soils during inundationMatej Maček, Bojan Majes, Ana Petkovšek, 2011, original scientific article Abstract: After construction, compacted clayey soils in different earth structures equilibrate their water content and suction with the local environment. In wet climatic conditions the compaction on the dry side of the Proctor curve, which enables a high layer stiffness during construction, may result in permanent deformation and softening during the lifetime of the structure. This paper presents the results of the tests, performed on a relatively large number of compacted test specimens, where the conventional index parameters, used to identify compacted soils, were supplemented with a suction–water-content curve and measurements of “mould” suction. Correlations were established between the optimum water content and the suction–water-content curve for representative samples, and the influence of the mould suction on the vertical deformation of the compacted samples during inundation in oedometers was studied. Keywords: oedometer tests, suction, swelling, collapse Published in DKUM: 13.06.2018; Views: 1109; Downloads: 92 Full text (391,47 KB) This document has many files! More... |
2. A laboratory characterization of soils and clay-bearing rocks using the Enslin-Neff water-adsorption testAna Petkovšek, Matej Maček, Bojan Majes, 2009, original scientific article Abstract: The application of the Enslin-Neff water-adsorption test for the determination of soil-index properties has been investigated on commercially available reference minerals and on real soils. The Enslin-Neff test is a simple and reliable laboratory method, which can provide important information about the behavior of soils, clay-bearing rocks and aggregate fines that are in contact with water. Although the test has been frequently used for bentonite testing, practically no results have been published about the physical meaning of the Enslin-Neff water-adsorption values for real soils. The results of this study indicate that the Enslin-Neff water-adsorption test can be used to obtain accurate values of some soil-index properties, such as the liquid limit, the plasticity index, the methylene-blue value, and the soil-water characteristic curve. Keywords: water adsorption, soil water characteristic curve, methylene blue value, soil suction Published in DKUM: 06.06.2018; Views: 1619; Downloads: 121 Full text (380,52 KB) This document has many files! More... |
3. Displacements in the exploratory tunnel ahead of the excavation face of Šentvid tunnelJure Klopčič, Janko Logar, Tomaž Ambrožič, Andrej Štimulak, Aleš Marjetič, Sonja Bogatin, Bojan Majes, 2006, original scientific article Abstract: Fitting the displacement function to the measured displacements enables the assessment of the stabilization process of the observed cross section and the determination of its normal behaviour. The displacement function consists of three parts. Whilst the third part has been successfully applied for several times and thus proven to be very well defined, the first two parts were defined only on the basis of numerical simulations. To overcome this deficiency and to obtain the necessary coefficients of the pre-face part of the displacement function, the 3D displacement measurements ahead of the face due to tunneling should be performed. Such measurements were performed in the exploratory tunnel of the Šentvid tunnel during the excavation of the main tunnel. This paper presents the Šentvid tunnel project, the method of the 3D displacement measurements, the results of these measurements and their interpretation according to the geological structure of the site with an emphasis on items important for the coefficients of the displacement function. Keywords: tunnels, exploratory tunnel, geodetic displacement measurements, pre-face displacements Published in DKUM: 17.05.2018; Views: 1503; Downloads: 101 Full text (660,40 KB) This document has many files! More... |
4. Analytical method for the analysis of stone-columns according to the Rowe dilatancy theoryBoštjan Pulko, Bojan Majes, 2006, original scientific article Abstract: In this paper a new analytical method to analyse the behaviour of rigid foundations stabilized by end bearing stone-columns is proposed. The stone column and the surrounding soil are treated in axial symmetric conditions as a unit cell. The stone column is assumed to behave as an Mohr-Coulomb rigid-plastic material with non-associative flow rule according to the Rowe stress dilatancy theory and the soil as an elastic material. These common assumptions, combined with equilibrium and kinematic conditions, lead to the simple analytical closed-form solution for the prediction of the behaviour for rigid footings resting on stone-column reinforced ground. The parametric study is presented to show the effect of dilatancy of the granular material on the deformations and stresses in the ground and its beneficial effect on settlement reduction. The results of the new method are compared with some already known analytical methods and some published field test results and observations. Keywords: ground improvement, stone columns, ground settlements, dilatancy theory Published in DKUM: 17.05.2018; Views: 1363; Downloads: 73 Full text (307,66 KB) This document has many files! More... |