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Catamarans are widely used in marine transport due to their advantages in stability and speed. However, their hydrodynamic performance is affected by the interaction between the two hulls, which creates complex interference phenomena influencing resistance and fuel consumption. Understanding and quantifying these interference effects is essential for optimizing catamaran, a key factor not only for operational efficiency and emissions reduction but also for achieving climate-resilient, energy-efficient marine trans...

The selection of foundation type for photovoltaic (PV) panels depends on several factors, including soil type, geographical location, site topography, groundwater level, and soil corrosion potential. Common foundation solutions for ground-mounted PV panels include ballasted foundations, ground screws, helical piles, and, most frequently, driven steel micropiles. The current study focuses on optimizing the design of foundations using steel micropiles by leveraging Cone Penetration Test (CPT) results to enable more ...

Most rivers in the temperate zone experience flooding due to snowmelt or heavy rainstorms. The lower Danube rivers has caused significant economic damages and in some cases even loss of human life. Understanding the relationship between the occurrence rate of Danube rivers flood events and climate change is crucial for flood risk management in Romania. Here we present a multiproxy and observational data set of floods from the lower Danube Basin Rivers over the last millennium. The results highlight that the lower ...

The work aims to characterize the slope instabilities present in the Taveiro Sand and Clay - Areias e Argilas de Taveiro - Formation, which occurs in the municipalities of Condeixa and Coimbra, in central-western Portugal. The Areias e Argilas de Taveiro Formation, of Upper Cretaceous - Campanian - age, is made up of successions of metric layers of red, and brownish or pinkish pelites, interbedded with coarse arkosic sandstones. It has as maximum thickness of about 170 m. A total of 27 slopes with stability proble...

In this work, a rock fall assessment was carried out in two distinct areas in southwest Angola. One is located next to Chapel of Nossa Senhora do Monte in the urban area of Lubango. The other area is located on the road between the city of Lubango and the tourist area of Tundavala. The rock mass of the first area belongs to the Tundavala Formation of the Chela Group and consists of quartzitic-sandstone with a sub-horizontal bedding attitude. The rock mass in the second area is composed of quartzitic-sandstone and ...

Among the important parameters determining the likelihood of occurrence of significant damage to engineering structures during an earthquake are the dynamic and seismic characteristics of the structures such as natural frequency, damping coefficient, and vulnerability index of the structure. In this article, the Nakamura method is applied to investigate the seismic stability of an earth-filled dam wall and the surface layer using microtremors. Measurements were taken at seven points on the dam crest and three poin...

The California Bearing Ratio (CBR) is a test designed to measure the bearing capacity of the subgrade during a construction of roads. It has also been used as a baring capacity test for unpaved aircraft runways and other transport areas. Nowadays, CBR is used as a proof and control test in evaluating the bearing capacity of subgrade and structural layers of roads. A distinction is made between the laboratory test and the in-situ test, which is nowadays no longer widely used. This is due to several reasons. It is p...

Following the increased use of sealing structures built in order to isolate historically polluted sites or to repair infiltrations inflicted to the levee of dams, it emerged the need to choose the right materials for constructing barriers using cutoff wall technique. The objective of this paper is to assess the range of suitable material combinations (water, cement and bentonite) in order to attain proper compressive strength, permeability and ductility requirements of such a structure. This paper proposes the rep...

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...

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 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...

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 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...

Soil unit weight is one of the most important parameter used in all geotechnical calculus related to design process of any type of constructions. Determination of this gravimetric -volumetric data can be done through laboratory tests in firm soils, or indirectly as itderive from some in situ investigations such as Cone Penetrations Test (CPT) or as severalgeophysical investigations such as Down hole, Cross hole, Logging P-S velocities, insoils which can?t support undisturbed samples (very wet organic soils or sand...

When developing oil fields, water flooding is often used to displace oil. In this case, effective oil production is possible with a detailed study of hydrodynamics in the reservoir. Recently, organic phosphors have been used for these purposes, which are pumped into the formation through injection wells. The spectral characteristics of the excitation (absorption) and luminescence of produced water with phosphors can provide information on the hydrodynamic relationship between injection and producing wells and the ...

The aim of the work is to create methodological provisions to justify the safe parameters of the thermal regime in permafrost rocks during the construction of underground complexes of small power nuclear plants in the Arctic region. The idea of the study is to assess the thermal regime of long-span mining excavations using mathematical modeling methods. To ensure the stability of underground mine excavations at the construction stage in the permafrost, the authors verify the use of various heat-protective systems....

The identification of the landslide preparation and development mechanisms is the key to the sustainable development of landslide and landslide-prone urban and mining areas. The understanding of the landslide preparation mechanism is necessary for landslide hazard and risk assessments and designing proper protection measures and monitoring. A new equation for calculation of a slip surface depth (of a landslide basis) was obtained, using slope morphological and soil strength parameters. A new elaborated approach fo...

For proper construction and operation of the industrial park there was proposed and already realised a 38 groundwater extraction well system from which optimum pumping rate is required to keep the groundwater level at required elevation. To address this challenge numerical groundwater modelling system using TRIWACO simulation package has been applied. The modelling package utilises finite element method (FEM) that can handle complex aquifer parameters for running quasi three-dimensional groundwater flow model. Bas...

In the study we dealt with the design of family-type civil constructions on competent foundation ground from geotechnical point of view. The geotechnical characteristics of the rocks that are necessary for the design of a civil construction were made in the laboratory of the PROIECT GEO SRL Company in Oradea. We analyzed the placement general conditions, the geomorphology and geology of the foundation ground required for the construction. The necessary data for the design of family-type civil-engineering foundatio...

This work presents a mechanical and physical characterization of rock material from different slopes located in the town of Coimbra (Central Portugal) and its adjacent areas. The slopes are designated by numbers from 1 to 7. Slopes 1 and 2 are placed in Lower Jurassic Formations. Slope 1 is composed by marly limestones and marls. Slope 2 is constituted by dolomitic limestone. Lower Cretaceous Sandstones outcrop in Slope 3. Slope 4 is placed in the Finisterra Microplate and Slopes 5, 6 and 7 belong to the ?Schist-G...

The aim of this work is to study the erosion and stability of rock cliffs. The selected sites are located in the Cuio and Kalohanda areas from the southern sector of the Baia-Farta municipality, on the coast of the Province of Benguela, central-western Angola. The fourteen studied sites are situated nearby fishing villages and present two distinct climate seasons: the rainy season and the dry season. The studied area presents a huge potential for economic activity related with tourism. The rock cliffs are mainly c...

Lazy Bledowskie well field located in the area of the Upper Silesia, was established in 1959. It consisted of max. 22 wells abstracting water from the Triassic carbonate aquifer (Olkusz-Zawiercie major aquifer). This aquifer is additionally heavily drained by Zn-Pb ore mines. Due to the decreasing demand for water and the deterioration of its quality, wells were gradually excluded from operation and liquidated. Currently, only 2 wells are exploited, pumping approx. 11500 m3 /d. As a result of the overlapping impac...

This research paper seeks to study the phreatic groundwater body from the Buz?u river alluvial fan. This goal is reached by creating a numerical model associated to a previously created conceptual model. The conceptual model was realized in three stages. Initially, a spatial schematization of the hydrostructure was created using the lithology collected while executing the hydrogeological boreholes. The second step consisted in studying the variation of the hydrogeological parameters in the hydrostructure. The para...

The precipitation surplus of the year 2009 has caused regional increase of the ground water table in the whole lowland region of Slovak Republic. The contribution deals with the analysis and the evaluation of the potential impact of treatment carried out through the Trn?vka River on the groundwater level regime in the adjacent area in the county town of Trnava. The aim of the article is to refute the false presumption of incorrect technical solution of Trn?vka stream training namely on the basis of similarity of t...

The wind energy is a modern and efficient solution that uses the air flow through wind turbines to mechanically power generators for electric power production, being an alternative to burning fossil fuels. Wind power is renewable, widely distributed, produces no greenhouse gas emissions, consumes no water and uses small land areas. A wind turbine converts the kinetic energy of the wind into electrical energy. The electrical power generator and the steel upper structure of a wind turbine are equipments where were i...

One of the most common geotechnical risk induced by earthquakes is liquefaction phenomena, which it has been responsible for building damages that directly influenced population and economy. The growing recognition of importance of geotechnical site conditions in earthquake-prone areas has been generated by concern about liquefaction observed in strong seismic motions that occurred during 20th century. The paper aims to substantiate the necessity of a rational assessment of uncertainties and risks related to seism...

The technology of Permeable Reactive Barriers in recent years is one of the most frequently developed methods of protecting the soil and water environment from pollution. These are zones filled with reactive material, in which during the flow of contaminated groundwater, contaminants are immobilized and/or their concentration is reduced to the limit values. Currently, there are relatively few deep installations compared to shallow systems (e.g. <10 m), resulting mainly from higher costs and technical difficulties ...

The article is concerned with underground and pit water hydrodynamic regime during Shumicha deposit Kizel coal basin storage underground treatment and after closure and inundation of self-titled mine. On the area of the deposit a heavy fissured-karst water level of Visean and Serpukhov stages carbonate deposits, fissured-stratal water complex of Visean stage coal-bearing series and fissured-stratal and fissured-karst water complex of Tourian stage of the lower carboniferous are developed. In vivo rivers Kosva and ...

Construction and Demolition (C&D) materials which consists mostly of concrete debris were deposited on landfills. The development of road network results in an increasing demand for building aggregates which are part of the road construction unbound subbase. For decrease of investment costs and prevention of spoiling natural resources, the C&D materials, such as fly ash, steel slag or recycled concrete aggregates (RCA), were applied as a subbase mix. Among many properties influencing the quality of road material, ...

A large number of structural damages reported during the past decades around the world associated with a high geotechnical risk have highlighted the major attention that should be given to the expansive soil category in engineering practice. For avoiding or mitigating the effects of clay expansiveness on civil engineering structures before construction, the identification of soil parameters related to swelling behavior is considered essential in solving geotechnical engineering problems. This paper aims to analyze...

Due to large widespread of loess deposits in many parts of the world and reported geotechnical problems arising from collapse susceptibility due to soil sensitivity to wetting changes associated with subsidence and damages, advanced and detailed analyses for quantification of specific characteristics are necessary in order to select the optimal technical solutions in terms of structure safety and stability. This paper presents the analysis of various experimental testing results, with particular emphasis on the co...

Tarnow region is supplied with water from intensively exploited groundwater and surface water intakes located in the small area between Dunajec and Bia?a rivers. Three groundwater intakes are a part of the Tarnow Municipal Water Service, i.e. ?wierczkпїЅw, K?pa Bogumi?owicka and newly constructed Zbylitowska GпїЅra intake, as well as the intake of surface water in Zbylitowska GпїЅra. The chemical company Zak?ady Azotowe in TarnпїЅw has groundwater intake located in TarnпїЅw-Mo?cice, and one of surface water locate...

The need for construction of new buildings is currently still growing. For construction are also used areas that were previously labelled as unsuitable or less suitable in terms of subsoil. The design, construction and implementation of building foundation, including subsoil modifications (foundation base) has a decisive influence on the building lifespan and its safety. This article presents an application of risk analysis method Umra (Universal Risk matrix analysis) to classify different types of subsoil. The me...

By the example of the new highway project in Moscow, the paper scrutinizes in detail the evaluation procedure of the differential and integral economic risk caused by geological hazards. Based on the analysis of engineering geological conditions at the construction site as well as the projected design for highway and bridges, the hazard of landslides, karst and suffusion processes and waterlogging was assessed. It is proved that for any scenario of landslide process (either deep or shallow landslides), the risk of...

In the framework of the work, the authors conducted an analysis of the possibilities of modifying the selected rank method to evaluate the groundwater vulnerability to cpollution in the area where a source of contamination is at least partly under the surface and the groundwater interact directly with it. Such an object is among others the CTL Maczki-BпїЅr sand mine, the workings of which are reclaimed with gangue (post-mining waste) from coal mines. The analyses of the groundwater vulnerability to pollution using...

On the night of February 21st, 2010, the county road 724 that connects the Malu cu Flori-Pucheni village was destroyed by a violent landslide, isolating it. In a few hours the road, together with the electrical, phone and water systems were moved downstream 30m along 100 meters. The area has been known for more than 100 years as being affected by landslides, which have appeared immediately after massive deforestation, regularly engaging local roads, house hold settlements. After the sliding in 1970, a series of wo...

This paper presents the results of a complex investigation executed in Bucharest, Romania by both geotechnical and geophysical techniques. Soil structure has been explored through 20 geotechnical boreholes at maximum 60m depth, which provided hundred of soil samples. A comprehensive set of experimental data on subsoil from oedometer and direct shear tests are analyzed in order to determine the stiffness and strength parameters for cohesive soils. For sands and gravels, the stiffness and strength parameters derived...

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 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...

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...

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...

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...

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...

This paper describes possibilities to use numerical models as significant aid in proposal of slope stabilization in Quarry. More accurately the proposal for excavation way of first soil overburden cut, which is mixed up with rock mass, to stabilize the slope. That is real case study which was performed for greywacke quarry situated in Eastern Bohemia. Since 2005 a small instability symptoms are observed on eastern general slope of quarry. Based on this fact the slope stability investigation started in detail one y...

The dynamic tests of reinforced concrete road bridge on the modern highway E-75 at the Kumanovo-Veles section has been carried out. The bridge is a prefabricated system of pre-stressed simple beams connected by the road deck cast in situ. The foundations were bedded in the stratum of shale. Under six of the columns the footings, that is, foundations, are the ordinary cascade ones, while three columns are founded on caissons, that is boxes in the very PДЌinja riverbed, nearby Katlanovo village . For the purpose of ...

Within the NATO Science for Peace Project 981882 “Site-effect analyses for the earthquake-endangered metropolis Bucharest, Romania” we obtain a unique, homogeneous dataset of seismic, soil-mechanic and elasto-dynamic parameters. Ten 50 m deep boreholes are drilled in the metropolitan area of Bucharest in order to obtain cores for dynamic tests and vertical seismic profiles for an updated microzonation map related to earthquake wave amplification. The boreholes are placed near former or existing seismic station...