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A case study concerning a drystone retaining wall that failed during construction, is presented. The site geology, the materials and their geotechnical characteristics are documented and discussed. The detailed site investigation performed allowed to define three geotechnical units: 1 - anthropogenic deposits; 2 - quaternary alluvial and colluvial deposits; 3 - Neogene alluvial fan. The third geotechnical unit, the Neogene alluvial fan, is mainly composed by dense and very dense sands, showed the best geotechnical...

This paper presents a new approach to the evaluation of dynamic soil strength based on the hypothesis of discreteness of the deformation process - a method of self-excited vibration. This method was first discovered at the sandy soil shear test. The destruction of the soil is viewed as cyclical and consists of two phases: the static and dynamic. On static stage deformation is slow, with energy accumulation. In the dynamic there is a rapid discharge, accompanied by a sharp increase in strain. Self-excited vibration...

The use of local soil as well as the recycling of existing structures such as road pavements using hydraulic binders is a beneficial technical solution, both in terms of economics and protection of the EarthпїЅs natural resources. Parameters of the soil stabilized with binders significantly affect the load bearing capacity and durability of the built structures. One of the important mechanical parameters applied in the analysis and design of soil structures is the modulus. Determination of the exact value of this ...

Bulgarian territory is subjected to impact of almost all negative and destructive geological processes and phenomena. The engineering estimation of these hazards requires knowledge of their origin, evaluation of potential occurrence of these phenomena, and their resulting risk. The liquefaction of weak soils under dynamic impacts is one of the processes that compose the geological hazards. This phenomenon occurs in certain areas during strong earthquakes. It involves a loss of bearing capacity of sediments, terrai...

During period of preparing the construction of halls of the industrial park, according to the geotechnical investigation were found adverse properties of soil. Below the ground surface was situated 5.5 m soft clay layer, deeper clayey gravel. Due to the nearby located river, the groundwater level was found just below the ground surface. Strict requirements to fulfilling first of all the serviceability limit state have led to the preparing the load test in real geological conditions in scale 1:1. Expecting load on ...

Metallurgical wastes are deposited in landfills or are being recycled, mainly as material used for engineering work. They are also sources of pollution in the groundwater environment. For this reason, it is necessary to explore environmentally safe ways of using them. Environmental impact assessments of waste can be made on the basis of static or dynamic laboratory tests. The alternative is to carry out lysimetric research. However, this kind of research is rarely performed due to the degree of complexity, cost an...

The article is an introduction to the issues of shaping the areas of former lignite mining surrounding the city of Zielona GпїЅra (Lubuskie voivodeship, Poland). The city of Zielona GпїЅra, seeking new investment areas, develops further areas, including those that have been former mine sites for at least 70 years. They have never been reclaimed. The remediation of former lignite mines, both technical and biological, is the responsibility of the mining plant and should be carried out in accordance with the law, how...

The article presents selected results obtained by using of electrical resistivity tomography method in searching of different, mostly anthropogenic objects at shallow depths. The anticipated depth of the object is up to 20m. These objects are relatively small with dimensions up to maximum in first meters in diameter. In terms of the shapes of these objects it is possible to define two groups. The first group consists mainly of the objects whose shape can be replaced by a vertical or horizontal cylinder. The second...

The object of this paper is represented by the analysis of a grid foundation for a light reinforced concrete structure. The need for this kind of analysis was imposed by the foundation ground conditions. In the case of sites presenting differentiate foundation ground conditions in the perimeter of a construction it is necessary a detailed analysis of the foundation conditions of the site and also, the behavior of the ensemble of the entire structure. So, is stent an adjustment of the foundation solution to the sit...

Exploitation of groundwater deposits exerts an influence on the state of the hydrogeological objects and the environment at large. The special study is required for the areas with the limited-use surface water. Province of Kyzylorda is one of such regions in Kazakhstan. Its water supply is mainly realized by use of underground waters of Kyzylzharminski deposit. Methods of mathematical modeling play an important part in the process of studying the hydrogeological objects, which are subject to the effect of high tec...

Many sports facilities were constructed in the Sochi area prior to Winter Olympics, 2014. We contributed to this by conducting the research of geological risks on the northern slopes of Aibga Ridge пїЅ the place allocated for construction of mountain skiing tracks. Initial data of the study comprised digital topographic model, field findings, and remote sensing data. All these were organized by using the instruments of MapInfo Geographic Information System (GIS). The research was based on the system-morphological ...

It is well known that the Russian North is rich in hydrocarbon resources, and oil production there requires long transporting pipelines. We studied geological and other natural risks associated with the project of construction of oil pipeline from South Bagan field, Komi Republic. To evaluate the risks we put into geographic information system (GIS) topographic maps as well as drilling data, remote sensing and own field survey materials. It is the system-morphological approach by A. Lastochkin that was used as a m...

Risk assessment includes quantitative estimation of damage to a linear engineering structure by exogenous geological processes. Remote sensing data processing using the mathematical morphology of landscape seems to be a promising approach of exogenous hazard risk assessment for linear structures, this issue is examined taking thermokarst plains as an example. The mathematical models of landscape morphological patterns for thermokarst lacustrine plains and thermokarst plains with fluvial erosion is a base of the su...

The determination of a stone column resistance and deformation is often based on empirical correlations, in пїЅ situ tests and previous experiences in similar geological conditions. In last decade, the stone columns are also designed using a numerical modelling пїЅ usually by finite element method (FEM). The most important parameters of a stone column are the unit weight which corresponding to the relative density, effective angle of shears strength and deformation modulus. Last but not least properties of the ori...

The article deals with the geotechnical calculations of the interaction of reinforced concrete storage boxes with subsoil at different loading states. From the numerical method point of view, this problem is solved by deformation variant of the finite element method. Defined the load states take into account the gradual filling of storage boxes with low and intermediate radioactive waste and final coverage of the storage boxes. More detailed are analyzed the results of the numerical calculations of vertical displa...

The article deals with the problem of determination of zones induced by excavation of underground work in solid granitoid rocks using numerical modelling under the assumption of Hoek-Brown's failure condition and DiederichsпїЅs conceptual model of behaviour of the rock environment around the underground work. Three fundamental induced zones around the underground work are characterized - the High Damage Zone (HDZ), the Excavation Damage Zone (EDZ) and the Excavation Influence Zone (EIZ) and the possibilities of th...

Productivity of geothermal reservoirs is often limited by capability of injection wells due to clogging of near-filter zone or increased viscosity of cooled waters. Especially for highly saline reservoirs, injection of cooled waters to water-bearing formation is often the only way of their disposal. In turn, this phenomena has little importance in case of low-mineralized waters. However, several water-treatment procedures can be used to recover valuable minerals, thus producing diluted water and salt concentrate. ...

Development of numerical methods allows on much more better examination of changes in foundation-soil interaction. However, there are still some areas which require more analysis and discussion, because results of simulations on are often divergent to the field tests. One of these problems is numerical modeling of displacement pile installation and proper consideration of its influence on surrounding soil. Application a simple FEM model can be not sufficient, by its limited application in changes of soil considera...

Most of researchers explain that shallow tunnels suffer higher damage compared to deep structures. Many numerical analyses were carried out in order to verify and compare the stresses, forces and bending moments acting on tunnel lining according with the seismic design. After tunnel modelling in MIDAS GTS NX to investigate the tunnel simulation in order to highlight the effect of static and dynamic load on the behaviour of tunnel lining for different cases and calculated the value of each mesh node based on 3D fin...

Reliability of a concrete pipe culvert was tested under rail and embankment loads. In the finite element model soil-structure interaction and nonlinear behavior of the materials were taken into account. After a preliminary study three influential variables as random were selected for presented approach to probabilistic model, i.e. concrete strength, soil density and its modulus of elasticity. Because various concrete parameters can be easily derived from the compressive strength only this parameter was selected fo...

The construction of some large industrial units and their endowment with oversized and heavy technological equipments, as well as their regular repair or replacement, led to the necessity of transporting some parts that exceeded both the gauge and the tonnage admitted on public roads. The choice of the route and the transport scheme (on one or more trailers) was made in such a way that requests would be as few as possible in order not to exceed the carrying capacity of the roads and bridges. However, in many cases...

In world, pipe jacking method had a very quick development. In last years there has been seen a tendency in metallic fiber reinforcement. In the first part the paper present o short description of the method and pipes reinforced with metallic fiber. The second part is dedicated to three dimensional numerical analize of pipe jacking method, to define their influence on pipe efforts, with considering the horizontal push force. In the third part are presented parametrical studies on fiber reinforced metal pipes used ...

The goal of the contribution is to elaborate the analysis and prognosis of groundwater level regime using numerical modelling to show the possibility of introducing technical measures which have to mitigate the unfavourable groundwater level regime in the vicinity of the hydraulic structure. For numerical simulation purposes a mathematical model by means of finite element method has been provided in right-side alluvium of the VпїЅh River with detailed concentration on endangered village in the vicinity of the hydr...

The Committee on Affairs of construction and housing and communal services of the Ministry of national economy of Kazakhstan approved the "Scheme of water supply and sanitation Kyzylorda", which is represented by the following decisions in choosing a water supply source. So, according to the first embodiment of the solution, the scheme drinking water supply was provided from two groundwater sources: Kyzylorda and Ky-zylzharminsky fields located on the right Bank of the city. Supply and return water was provided th...

The sedimentary environments are in general very important aquifers because of the following characteristics: high permeabilities, storage capacity, the interaction with the surface waters. The exploitaition of this types of aquifers it is significant because, among other things, this aquifers are easily accessible (in general we donпїЅt need complex systems of capture and in most cases are enough wells ans/or drilling between 10-100m depth). Must of the aquifers structures from the south part of Romania are usual...

Nowadays, after intervals of time without rainfall, heavy rain with very high flow rates in very short time are increasingly more often. If extreme rainfall events, storm sewer networks can not take storm water flows, which frequently occurs with flood damage large, often with loss of life. Duet o the fact that rainwater flows to the emissaries in time, the water table drops. Analyzing the frequency of extreme phenomena rainfall and using climate scenarios we can adapt technical regulations related to sizing colle...

Studying of regularities of forming of fresh underground waters of the Akmola region of Northern Kazakhstan allowed to reveal the main regularities of distribution of fresh underground waters against the background of waters of the raised mineralization. The role of tectonic violations in forming and distribution of underground waters influence, and also influences of a lithology of the water containing deposits on nature of circulation and the chemical composition of underground waters is established. Distinction...

Waste rock storage resulting from underground mining works or surface workings, the power plan ashes well as metallurgical and steel waste, is done in the form of dumps. Embankments as well slopes (which are inclined surfaces side that separates positive forms of relief), are characterized by the same geometrical elements, respectively, height and angle of embankment and their stability depends on the physic-chemical and mechanical properties of rocks that compose them. Cohesion and internal friction angle are the...

This paper consist of creating a conceptual model of the first aquifer identified in the central area of Bucharest. The conceptual model was developed in three stages: the spatial schematization, the parametric schematization and the hydrodynamic schematization, based on data from geotechnical boreholes. Mathematical modeling of groundwater flow requires knowing the entire system, from the geological and spatial distribution of permeable geological structures to hydrogeological parameters of the aquifer (hydraulic...

The two-dimensional profile curves created by Barton are often used in geotechnics for the determination of the rock joint coefficients. These two-dimensional profiles of solid surfaces show self-affine properties, i.e. they are scaled differently in x- and y- directions. Similarly, the three-dimensional reliefs (3D) of solid surfaces are scaled differently in z-direction in comparison to x- or y-directions. Therefore, the vertical sections of surface reliefs (two-dimensional profiles) are self-affine curve (self-...

Usually the frost heave of soils causes damages to low-rise buildings, road paving, and pipelines. However, a few years ago unusual deformations of a building supported by 18 meter piles were found. It was a cooling house designed for fish storage at the temperature of -22пїЅ-24пїЅ?. The building was 8,4m high; its plan dimensions were 24?42m. To protect the ground against the frost penetration a 0,9 m layer of light gravel under the concrete floor was filled and an electrical heating system under it was set up. T...

Many oil and gas low permeable reservoirs have been stimulated to enhance productivity. Acid fracturing is one of the commonly used well stimulation treatment in carbonate formations, such as limestone, dolomite, and chalk. Carbonate reservoirs are good candidates for acid fracturing since strong acids such as hydrochloric acid react easily with carbonate. The acid reacts within the fracture to create a differentially etched surface that will maintain a conductive pathway. Habitually, a pad fluid is injected ahead...

Conditions of manifestation, feature of chemical and isotope composition of soda groundwater of the southern part of Kuzbass - the world's largest coal basin have been studied. It is shown that soda groundwater is widely developed here within of coal-bearing sand-clay of Paleozoic sediments, are confined in zone of slow water exchange at depths from 100-200 up to 2000 m. At the same time soda groundwater are presented quite variously on chemical and isotope compositions, that has allowed to allocate them in three ...

The paper describes and analysis loess substrate collapsing under embankment as a result of flooding. The threat of huge settlements is wide spread on large loess deposits areas especially in south part of Asia. The popular in Russian Federation and common used method developed by authors is the compaction of substrate by soil columns. It is used in a variant covered with geosynthetic as barrier and reinforcement under an embankment. Authors present results of numerical calculations in direct numerical determinist...

The paper presents the physical and mechanical behaviour of an expansive clay, coming from a site in Cluj-Napoca, Romania enhanced by a polyethylene waste material. Given the current research directions of international projects, this paper fits the less studied theme of the usage of recyclable materials for soil stabilization. According to recent studies, in EU just 40% of waste materials are recycled and this low percentage opens a wide perspective for the re-usage of these materials as fillers in stabilized soi...

The article deals with numerical analysis of vertical normal contact stress in subsoil of foundation slab of 16-storey monolithic reinforced concrete frame building situated in Kiev, Ukraine. The foundation gap is located 11.65 m below the level of surrounding terrain. Numerical calculations are verified with real measured values of contact stress (published in Lazebnik, 1998) in four different cross sections of foundation slab. The problem is solved as spatial (3D) with complex interaction of пїЅupper structure п...

The article observes the results of numerical simulation of the interaction of socketed shafts with rocks under the action of horizontal loads. The study revealed the following features of deformation and failure of the system "shaftпїЅ rock mass". Analysis of the obtained results confirmed the conclusion previously made by other researchers that the curve of deformation of the socketed shaft may be approximated by bi-linear dependence, in which the inflection point corresponds to the end of the linear section of ...

Geotechical engineering combines strict mechanical rules with a random nature of natural soils. That is why reliability-based approach to geotechnical design is still not fully appreciated by the engineers. Large variability of soil parameters and uncertainty of computational models emphasize the importance of experience and engineering intuition followed by over-standard number of testing procedures of both: the soil and the structure. Conventional university education may provide the student with the knowledge a...

The construction of a numerical hydrogeological flow model must be preceded by obtaining necessary information. Quantity and reliability of information may extensively impact on the process of model construction and its later calibration, and as a result пїЅ the quality and reliability of prognostic calculations. The article deals with sources of data required for a numerical groundwater flow model and it presents various types of data resources. The model is based on a number of overall nature materials, such as ...

This study comprehends the stability assessment of seven slopes with Pre-Cambrian rocks and located in traffic-access areas of SW Angola, one (Slope 1) is located on the road access from Lubango to Tundavala Gorge, another slope belongs to the CaholoпїЅs area near Humpata (Slope 2) and five of them (Slopes 3 to 7) are located on the LebaпїЅs Sierra, along the sinuous hair-pinned sections of the National Road 280. Slope 1 is composed by quartzites, volcanic rocks and lutites. Slope 2 shows sandstones, lutites and q...

The studied area is located in the vicinity of Rashid branch, part of the Nile Delta. This region is part of one of the most important aquifers in the world. The review of published information indicates that the existing zone of interaction between groundwater and sea salt water is complicated by the variable lithological composition in vertical and horizontal directions and by the relationship with the River Nile waters. Object of study are the upper parts of the aquifer where favorable conditions for natural sa...

Previous researches have shown the possibility of using organic-mineral additive based on glyoxal for injection strengthening of soils in roadbases and engineering communications. Saponite containing material was used as mineral component in the composition. Saponite containing material is a solid phase, extracted from the circulating water suspension of the kimberlite ore dressing. Modification of the sandy soil by the tailored organic-mineral additive content increases its specific cohesion up to 50 times. It wa...

The paper starts with the presentation of some general elements for characterizing, from morphological, geological, climatic, rainfalls and hydrographical point of view, a national road routing, highlighting the specific particularities which are concerning the study of the instability phenomena. Further on, are presented the types of instability phenomena present on the national road routing, including the general causes that produced them. The paper ends with the analysis of two case studies, considered as being...

One of the common applications of geosynthetics is their use as reinforcement for aggregate and soil layers. Geosynthetics improve the mechanical properties of the reinforced layers, which are originally, due to various reasons, insufficiently protected. Therefore, the use of geosynthetics allows for bearing heavier loads thanks to the soil-reinforcement system and an extended material durability. This article describes the laboratory tests of mechanical properties of a hexagonal geogrid made of polypropylene used...

Based on a real-life example, the report presents the methodology and the process of adapting in situ measurements from static CPTu probing for an application in a design process, using direct methods of driven pile capacity estimation. The report discusses two approaches. One of them is based on a real-life original CPTu measurement involving preliminary soil assessment while the other one is based on the initial averaging of the measurement values qc and fs. The paper provides methods of averaging cone resistanc...

The experience accumulated in Romania and worldwide by means of studies, design and control of the behaviour of many shallow foundations has rendered evident the existence of some soils, such as the loessial soils and the plastic clay fills, which are characterized by a high deformability, due to their sensitivity at wetting. One of the defining feature of these soils is their пїЅcontractancyпїЅ under the simultaneous action of compression and shear stresses. The macroporous soils, such as the loessial soils, have...

This paper aims to analyse the link between the hydraulic structures and the watercourse riverbed. In this regard the Epurasu branch has been chosen as a case study area. This is a secondary branch of the Lower Danube, located between the 341-334 kilometers of the Danube River. Epurasu branch is in an advanced state of silting/colmation, possibly due to the unfinished damming works, from the mid-80s of the last century. Thus, over the years, various solutions have been proposed to ensure the longitudinal connectiv...

This article shows the results obtained by applying a study method of the convergence of structural models, for the particular case of a structural model from the geotechnical domain. For this purpose, is used the study method of the structural models convergence, already widely used in the field of research and CAD - CAE design. For a larger relevance and utility is presented the convergence study of a structural model for a ground section to which it applies a uniform load. The problem of ground compaction is so...

This paperwork aims to present the correlation between the Modulus of Deformation, E as a physical parameter and the internal friction angle of the soil, ? as a resisting parameter of soils. Assigning the resisting parameters to soils shall be reliable and when there is a suspicion in their values derived out of a test, than they shall be compared with other tests used to determine the shear resistance. To give the correlation between the Modulus of Deformation, E and the internal friction angle, ? the results obt...

In the paper the results of the study of the crack resistance of circular shaped fiber reinforced concrete tunnel linings are presented. On the basis of laboratory testing of linings and numerical simulation of their behavior (FEM) is shown that the deformation of fiber concrete can be considered as the deformation of solid, elastic, homogeneous medium. In addition, the analysis of stressпїЅstrain state of these linings shows that their failure is caused by stable propagation of the single crack, which usually for...