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When studying the mechanical behavior of hydrated binders, it is necessary to prevent hydration contraction tensile failure in order to properly characterize the mechanical properties of the material. This is regulated by standards for cement testing, however for the case of water-cement-bentonite mixtures the influence of standard sand is not thoroughly studied. Since the hydration shrinkage and water suction is different for cement and bentonite, a range of eleven combinations of water-cement-bentonite were used...

In this paper, we consider an algorithm for assessing the stability of a geotechnical system and its individual sections based on a basic model. As a basic model, it is proposed to use a set of models used at the design stage of sections of the geotechnical system. When assessing the stability of individual links of the geotechnical system, and the group stability of the analyzed area of the geotechnical system, the approaches of the theory of automatic control are used, taking into account bifurcation parameters ...

This paper presents a study on the stability of nineteen excavation slopes in metamorphic and carbonate rock masses along roads and urban areas in Central Portugal. The slopes studied are formed by phyllites intercalated by metagreywackes belonging to the Xisto-Grauvaquico Complex; quartzites and limestones of the Bussaco Ordovician-Silurian synclinal; schists of the Crystallophyllic Complex; and limestones and dolomites of Jurassic age. Road safety and urban areas are threatened by stability problems. In the asse...

The paper deals with an analysis of the settlement of a tank. The tank has a diameter of 18.6 m and a volume of 1760 m3. The subsoil consists of soft sandy clays and clays of low to medium plasticity. The tank has been founded on a slab of a thickness of 0.2 m. A consolidation layer of compacted gravel of a thickness of 1 m was created immediately below the foundation slab. The soft subsoil was improved using the stone columns. The stone columns were installed using vibro-replacement bottom feed technology. The st...

Landsliding is among the most massive and active exogenous processes. Now they increasingly manifest in permafrost zones due to climate change and require close attention and careful study. Analysis of the territory most prone to these processes, one of the largest islands in Northern Canada, Banks, confirmed earlier studies of landslide processes in this zone, which indicate a relationship between increased activation of landslides and abnormally warm summers. The study and assessment of the landslide focus param...

The aim of the research is to examine the geotechnical stability of the historical mining works for the Kamenny Vrch deposit with a high percentage of limestone, including examination of the geology of the mining works for the selection of a suitable deep mining method. A complete inspection of the mining works was performed to examine the geotechnical condition of the mining works. Convergence measurements were carried out to determine the stability of individual parts of the mine. Further, a geological descripti...

The study area is located in northern Bulgaria in the northwestern part of the town of Kozloduy, Vratsa province. From an engineering geological point of view, the region falls within the Lom Engineering Geological Area, which is characterized by the presence of loess sediments (silty clay sands and sandy clays), which are with high porosity, non compacted and susceptible to collaps?. Other dangerous engineering geological processes are landslides and river erosion. The Kozloduy lowland is one of the Danube lowlan...

The article deals with the geotechnical design and assessment of the foundation of a statically difficult bridge structure founded in complicated engineering geological conditions. Bridge structure No. 223 is part of the D3 motorway situated above the Hricov reservoir near the town of Zilina (Slovakia). The realized engineering geological survey showed that the geological composition of the subsoil is nonhomogeneous and complicated (occurrence of Quaternary soils and Mesozoic rocks). The physical and mechanical pr...

The paper deals with numerical analysis of the stability of an embankment reinforced using a geogrid. The analysis is mainly focused on the impact of the Rinter parameter, which represents the ratio of the soil-geogrid interface shear strength to the shear strength of the soil, on the deformations, and the global stability of the embankment. The properties of the soil-geogrid interface were measured using a modified large size direct shear test apparatus. The biaxial geogrid made of polypropylene with a tensile st...

The development of transport requires new transport routes. When designing and implementing them, we cannot avoid the construction of tunnels in our mountainous country. One part of the static design of the tunnel is the assessment of the structure on fire. The fire of cars in road tunnels can be modeled more and more accurately thanks to improving numerical models (CFD simulations, Fire Dynamics Simulator FDS [1]) as well as an extreme increase in computer performance. The results of these investigations are appl...

Expansion of the transport infrastructure of the Krasnodar Territory (Russia), in connection with the development of new land plots, as well as an increase in the tourist flow to the region, it became necessary to build facilities in difficult engineering and geological conditions on landslide slopes in hard-to-reach areas. As one of the measures to protect against landslide movements of surface rocks and to strengthen weakened sections of slopes, structures of bored piles, restrained in non-displaceable soils, ar...

The quality of agricultural products grown and collected at the facilities of the agro-industrial complex and the raw materials obtained for various industries largely depends on the ecological state of the geological environments. To quickly eliminate possible contamination, it is necessary to solve the problems of their early detection, localization and forecasting with the help of special technical means. In this aspect, it is promising to use groups of geoelectric control methods that allow to effectively regi...

At present, in time of sustainable environment, people views are increasingly focused on the energy performance of buildings. In recent years, there has been a huge increase in the rate of insulation of buildings. Thermal insulation of facades and roofs of buildings has been theoretically mastered and practically realized. Recently, we have also encountered thermal insulation of foundation structures to prevent heat leakage through massive concrete foundation structures into the subgrade. As clear from the availab...

The paper analyses in detail size of vertical deformation (settlement) for various loading states that may occur during construction and operation of Hydropower Plant (HPP) in Gabcikovo. During construction and operation of the HPP complicated loading states were applied onto sealing elements of underground tank and subsoil of the HPP foundation. Geotechnical calculations, a total of fourth load states modelled, taking into account significant changes in the stress state and deformation in the subsoil and on the s...

In Romania before 1990, over 600 hydro-power plants were built with dams and lateral dikes made of local materials. In order to be completed as soon as possible and with material savings, the protection screens were improperly executed. In many cases there is no continuous protection screen along the dam and in its vicinity, but only from place to place, intermittently. The same problem is with the lateral dikes of the lakes. In these conditions, at the hydroelectric power plant commissioning, the infiltration imm...

A mining tailings pond is an engineering construction used for the safe deposition of unexploitable mining waste from mining facilities. This contribution presents a stability analysis of a mining tailings pond. The credibility of the results, when considering the stability of a tailings pond, is conditioned by the aptness of the computing model of the tailings pond, which actually describes not only the constructional arrangement, but also the properties of the geomaterials of the construction of an tailings pond...

The processes of liquefaction of water-saturated soils under dynamic impacts are one of the many negative and destructive geological processes and phenomena that constitute the geological hazard in Bulgaria. Processes of liquefaction of water-saturated sediments on the territory of Bulgaria are registered during almost all strong earthquakes affecting its territory from both local and regional sources. Specific cases have been described by a number of authors. These processes lead to loss of bearing capacity of wa...

The Dobsina dam is a part of the water management system ?Dobsina? which consists of the Palcmanska Masa reservoir, the Vlca Dolina hydroelectric power plant, and the Dobsina afterbay reservoir. Palcmanska Masa and Vlcia dolina dams were built in the years 1956 -1958, Dobsina dam in 1960. It is an earthfill dam, and the body of the dam is divided into the left and right part by a functional outlet block, which is situated in the valley alluvial plain. On the left side of the dam, the sealing was built of stabilize...

The study of erosion processes in settlements is a pressing issue since they develop rapidly sometimes. The purpose of this study is, however, to identify the dynamics of erosion activity in settlements of the Middle Ob region. The study objectives are focused on identification of hazardous areas, which is necessary for making informed decisions related to well-minded bank protection. The targets of the study were settlements of the Middle Ob region (Pasol, Vata, Vysoky Mys villages) within the latitudinal stream ...

The paper deals with the laboratory testing of the shear strength of the soil-geotextile interface. Two samples of soil were tested, i.e., coarse-grained poorly graded sand and fine poorly graded ash. The soils were reinforced using the Thrace WG80 black woven geotextile, which is suitable for road, railway, and geo-bag applications. The tests were executed using a large-size direct shear test apparatus. The shear strength of the interface was determined using the large-size direct shear test apparatus. The ground...

The paper deals with an analysis of an endless thin-walled beam on an elastic subsoil. Winkler's subsoil model has been used for modeling the subsoil. The analysis is presented in an analytical form for beams of infinite length. The analytical solution includes the analysis of both bending and torsion of the beam. In the solution of the bending of the beam, the effects of shear forces have been taken into account. For torsion analysis, an open cross-section has been considered, including the effect of cross-sectio...

Concrete constructions are normally reinforced with steel, which is protected by high alkalinity of the concrete against the effects of corrosion. The steel reinforcement corrosion is causing by the reducing the alkalinity of the concrete or by the presence of chlorides in such an aggressive environment which make reduction the cross-sectional area of the reinforcement and a loss of cohesion. Underground constructions are often found in an aggressive rock environment and the protection of steel reinforcement is mo...

The applied research focused on the stabilization process of unstable soils has pointed out the possibility of using different types of organic fibers and eco-friendly binders in terms of their effects on mechanical performance characteristics, cost savings and environmental impact. The experimental applications carried out under small-scale laboratory conditions aim to demonstrate the applicability and effectiveness of bio-composite wool-based products mixed with different binders in clayey stabilization works or...

The locality on the Hron River close to the town of Banska Bystrica (Slovakia) was selected, based on the study of effectiveness of the hydro-energetic potential of the Slovak Republic and on the engineering-geological survey, for the construction of a small hydropower plant in Salkova. In the process of the environmental impact assessment, it was required to determine the impact of the proposed hydraulic structure on the surface and groundwater level regime of the adjacent area. Therefore, the 3-D mathematical mo...

The determination of the physical and mechanical parameters and properties of the soil is an important part of the design of geotechnical structures. The soil characteristics can be specified by laboratory or field testing. In Slovakia, one of the common field tests, used for determination of the soil characteristics during the engineering geological investigation, is the dynamic penetration test. In 20th century, the dynamic penetration test passed through substantial development and simultaneously, the correlati...

Fiber Bragg Grating (FBG) sensors are used worldwide in structural health monitoring as a highly effective strain sensing method. Compared to traditional strain sensing methods in geotechnics, such as measurement by extensometers, deformeters, or strain gauges, FBG technology is beneficial in many issues, such as small dimensions of the sensor, easy and fast installation, long-term stability, immunity to electromagnetic interference or possibility of having dozens of sensing points on a single measuring cable. One...

Stone columns are one of the most-used technologies of soil improvement in Slovakia. The stone columns installed using the vibro-replacement technology cause the change in the stress state and the properties of the surrounding soil. These changes are often not taken into account in the design. The paper deals with determine the change of the stress state and oedometer modulus in the soil around a single stone column. The calculations have been prepared in the form of a parametric study. The selected properties of ...

The presented article is devoted to the development of equivalent models of geological environments based on the grid method, taking into account possible oil pollution resulting from emergencies at oil storage and oil refining facilities and amounting to about 25% of the total share of leaks, as a result of which an average of 2% to 10% of extracted raw materials is lost annually in the world. The main sources of emergencies at oil storage and oil refining facilities are examined, and it is shown that their resul...

The problems of potable quality groundwater pollution have now become one of the most important on the Earth. According to UN, about 2 billion people currently lack access to drinking water. Climatic change and increased negative impact of anthropogenic factors significantly affected the quality of water resources. Groundwater is the main source for drinking and other domestic purposes. Many developing regions of the world suffer from shortage of safe drinking water. Basically, the main reason is that due to globa...

Pile driving technology remains the most widespread method in Arkhangelsk where the presence of soft soils is an engineering-geological feature. High quality of the pile shaft in the soft soil is guaranteed by using precast piles. New construction in the urban conditions is mainly carried out next to the adjacent buildings. During construction of a multi-section building ground works and pile driving are sometimes performed separately for each section but not for the entire building at once. The monitoring of pile...

Earthquakes are violent movements of the Earth?s surface resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. The movements are characterized by rapid variations of direction, speed and acceleration. The present paper analyzes the response of the structures and the behavior of buildings during high-intensity earthquakes. The target areas of the study are Galati and Suceava municipalities, located in Romania, at varying distances from the seismic hotspot situated in the C...

The effective application of the evils in the construction, including road, an important area of research is to identify the characteristics of physical and chemical processes and their hydration mechanism composed gold-cement binders. By chemical, mineralogical, derivatographic, spectroscopic and X-ray analyzes established physico-chemical properties of fly ash of thermal power hydroremoval Rudnenskiy AO SSGPO (Kazakhstan). It was determined that the hydraulic ash is acidic, with a high content of SiO2 and Al2O3 ...

This paper presents a theoretical study on the free convection of pore water in saturated permeable rock mass during artificial freezing. Artificial freezing technology is widely used in the construction of mine shafts, tunnels and other types of excavation that take place under high water content conditions or conditions of high levels of groundwater seepage in soil and rock. A qualitative analysis of artificial freezing in water-saturated permeable rock mass shows that the effect of free convection can be signif...

Hydrogeological hazards are very common when dealing with underground excavations, and they can bring about a damage both for the tunnel (e.g., tunnel inflow) and for the environment (e.g., water resource depletion). The paper proposes an example of the contribution of hydrogeology to risk management in tunnelling. In particular, the two following issues are addressed: how tunnel inflow can be assessed, and how its impact on water resources can be quantified. These issues are discussed based on the state of the ar...

This article is devoted to the problem of organizing geo-ecological monitoring of water supply for territories with conditions of active karst processes. In these cases, the task is complicated by the difficult hydrogeological conditions of the locality and the high vulnerability of karst groundwater resources to pollution due to their complex hydrogeological structure. Karst water exchange systems are characterized by high natural and anthropogenic vulnerability of groundwater resources, and their extremely low a...

Creation of information system of the Republic of Kazakhstan groundwater resources and reserves implies the accumulation, systematization, processing and analysis of historical and operating data about status and use of groundwater and environmental bodies related to it. The system includes different-scale geoinformational models. Each model is built on the basis of materials contained in bases of semantic and graphical data. Semantic database contains structured text and numerical information. Spatial data are in...

The study area is located in northeastern Bulgaria (Northern Bulgarian Black Sea Coast), between the Ikantalaka locality, Balchik municipality and the village of Bozhurets, Kavarna Municipality, Dobrich district. From an engineering geological point of view, the region falls within the Balchik Landslide Area, which is characterized by old and recent landslides with linear-stepped and packaged construction. In the formation of landslide processes in the study area, the direction of subsidence and the angle of incli...

In the framework of reconstruction of the Old Bridge, two exploratory wells were made in the channel of the Danube River. The depth of the exploratory wells was up to 55 m below the modified terrain around the bridge pillars. The role of the exploratory wells was verifying the thickness of Quaternary sediments and simultaneously verifying Neogene soils properties located in the channel of the Danube River. The exploratory wells verified that the Neogene subsoil of the Danube River is predominantly made up of silty...

Groundwater in the territory of Kazakhstan is present in very diverse hydrogeological conditions and is subject to powerful human impact. First of all, it is manifested in groundwater pollution. Basic sources of groundwater pollution are gaseous, liquid and solid substances and production wastes of mining and gas and oil producing complexes industrial enterprises, agricultural facilities, cities and large population centers, large dumps of production, domestic and radioactive wastes etc. They cause habitat degrada...

The research is aimed to demonstrate the possibility to find the quantitative characteristics of the processes developing in the landscapes of the thermokarst plains with fluvial erosion, using a momentary set of landscape metrics without long repeated observations. We examine a mathematical model of the morphological pattern of the thermokarst plains with fluvial erosion in the case of the asynchronous start developed in the framework of the mathematical morphology of landscapes. We have obtained empirical data o...

The paper presents a study of hydraulic modeling of the drinking water and sewage distribution network in Beclean City, Bistrita Nasaud County, from Romania. This study includes a calibrated simulation of the flow through networks (systems), which allows the elaboration of a future strategy of developing the networks (systems) of water and sewage. The need to develop hydraulic models as accurately as possible results from the fact that, by creating and calibrating the hydraulic model of a system, a variety of syst...

The region in question is located in northeastern Bulgaria, 2.8 km southeast of the village of Balgarevo, Kavarna municipality, in the protected picturesque area "Zelenka". The study area is part of a coastal zone with a length of 2.5-3.0 km, where several descending springs are established. During the mapping in September 2018 in the studied area a zone of groundwater discharge was established in the slope at an absolute elevation of 36 m. Water from this area flows down the slope, forming a scenic waterfall. The...

In the article, the results of the estimation of an influence of soil back pressure of the lower slope on the distribution of the landslide pressures between the rows of the piles of the multi-row retaining structures. The conditions of a stable soil and an unstable one as well as a dugout from the lower slope side have been considered. The analysis has been carried out on the basis of the distribution of the forces between the rows of the piles according to the spatial numerical model study data of the multi-row ...

In the article is analyzed the influence of relative stiffness and bonding of the "foundation -subsoil" interaction system on the value and distribution of the vertical normal and shearcontact stresses. The analysis of the calculated deformations of the foundation focused onthe qualitative and quantitative evaluation of the non-uniform settlement, respectively therelative deflection and flexibility of the foundation. In terms of relative stiffness areanalyzed the shallow square foundations from the "perfect rigid?...

In the article is analyzed the influence of relative stiffness and bonding of the "foundation -subsoil" interaction system on the value and distribution of the vertical normal and shearcontact stresses. The analysis of the calculated deformations of the foundation focused onthe qualitative and quantitative evaluation of the non-uniform settlement, respectively therelative deflection and flexibility of the foundation. In terms of relative stiffness areanalyzed the shallow strip foundations from the "perfect rigid? ...

Optimum exploitation of the agricultural lands in the presence of polluted aquifers by surface sources requires close monitoring of the groundwater level in both periods of massive rains or, on the contrary, during drought seasons. The non-steady flow in the aquifer groundwater is described with the Boussinesq's partial differential equations. The boundary conditions consist of the groundwater level required at the margins of the analyzed area, in conformity of the pollutant emissaries, using the double steps meth...

Currently, geotechnical monitoring systems are used to solve the problems of protecting the life-supporting and technical objects from possible catastrophic scenarios during the life cycle of objects as a whole. They allow us to assess geomechanical changes in the geological environment, as well as to carry out technological control of buildings and structures in order to form a predictive assessment of the possibility of man-made disasters. It is determined that the main problem of emergency situations on technic...

A serious challenge for the construction of Sofia Metro is the shallow groundwater and the high water abundance of the hydrogeological units that are crossed by the construction route. The dewatering of the excavations for the facilities that are supported on deep foundations and the tunnels is most often associated with large and long-lasting local depressions of the water table. The joint action of the drainage systems around the metro stations and tunnel sections built simultaneously or in overlapping time inte...

A computer hydrogeomechanical 3D model of a fragment of a soil tailing dam has been developed. The model allows investigating both geo mechanical and filtration processes and also their collateral influence on a condition of soils of the bulk protecting dam and the alluvial beach of the tailing. The following options of development of a hydrogeomechanical condition of a soil dam have been considered: an initial state at the current operation parameters, increase in level of water-saturated mining deposits and the ...

Human impact along with other elements of the environment has a great impact on the processes in the river basins. River meander dynamics and mobility are important indicators of environmental change related to climate changes and anthropogenic activities at local and river basin scales. This paper presents a study of spatial and temporal changes meandering Alazani (Georgia) in its middle stream and downstream. Alazani is the border of the country and the bank erosion here has the environmental and political impor...