This study analyses and presents a technical comparison of seepage estimation from 11 empirical equations with measured seepage losses by the inflow-outflow method from two lined and unlined secondary irrigation canals sub-divided into different reach lengths. A significant margin of error was observed between empirical and inflow- outflow methods, hence modifications in empirical equations were performed. Results reveal that the average seepage losses observed in unlined and lined canals by inflow-outflow method were 9.15 and 3.89%, respectively. Moreover, only the Chinese equation estimated seepage losses for an unlined canal as similar to observed losses (0.11 m ³∙s ^–1) whereas the Indian equation estimated similar results for a lined canal to those observed in the field (0.09 m ³∙s ^–1). However, the rest of empirical equations were modified in accordance with error percentage with regard to the observed losses. The empirical equations were then observed to estimate reliable results of seepage.

Flood embankments have played an important role in flood protection systems for centuries. Tightness evaluation of water structures should result in determining whether floods may cause seepage incidents, consequently leading to their damage or even destruction. It is assumed that the time of water passage from the river to the protected area under steady-state conditions can be a good indicator of the embankment resistance to long-term water rise. The curve of water passage times shows the values obtained at different ordinates of the dammed water and can be regarded as a characteristic parameter of flood embankment tightness. Determination of the water passage time ( T_p) additionally requires finding the trajectory along which this time is the shortest possible. However, there is no need to analyse the unsteady filtration, which requires the determination of an initial condition and the course of time-dependent boundary conditions. Engineers in practice, often use the time T_pp which elapses from the beginning of flooding to the occurrence of seepage in the protected area. The relationship between the passage time ( T_p) and the seepage onset time ( T_pp) was analysed on a model example. Practical use of the curve of passage times is showed on the example of the reconstruction of the left-bank Warta embankment in the area of Konin.

The research paper reviews issues associated with the impact of groundwater flow on soil characteristics and parameters, hence, the entire structure of a building set on it.Water seepage through the ground, building subsoil or structural elements of buildings made of soil affects the soil skeleton and may lead to changes in the arrangement of individual grains relative to each other, i.e., a modified soil structure. Soil solid phase (soil skeleton) deformations resulting from seepage forces are called seepage-induced deformations. The article characterizes typical seepage-induced deformations and specifies a criterion defining the beginning of the phenomenon. The case study involved using data on cracks and deformations in a historic building, as well as water seepage in its subsoil. Seepage was analysed, and zones where the seepage process initiation criterion was exceeded, were determined based on subsoil water level monitoring data. The determined zones coincide with the location of building cracks and scratches and confirm the possible cause behind building damage.

The possibilities of remote sensing techniques in the field of the Earth surface monitoring and protection specifically for the problems caused by petroleum contaminations, for the mapping of insufficiently plugged and abandoned old oil wells and for the analysis of onshore oil seeps are described. Explained is the methodology for analyzing and detection of potential hydrocarbon contaminations using the Earth observation in the area of interest in Slovakia (Korňa) and in Czech Republic (Nesyt), mainly building and calibrating the spectral library for oil seeps. The acquisition of the in-situ field data (ASD, Cropscan spectroradiometers) for this purpose, the successful building and verification of hydrocarbon spectral library, the application of hydrocarbon indexes and use of shift in red-edge part of electromagnetic spectra, the spectral analysis of input data are clarified in the paper. Described is approach which could innovate the routine methods for investigating the occurrence of hydrocarbons and can assist during the mapping and locating the potential oil seep sites. Important outcome is the successful establishment of a spectral library (database with calibration data) suitable for further application in data classification for identifying the occurrence of hydrocarbons.

In this study, an old rotational landslide that has reactivated in the NW sector of an open-pit mine operated within the gneiss rock unit was evaluated for geological and hydrogeological properties. The pit slopes were susceptible to mass movement when there were variations in water inflows. Considering this fact, a conceptual numerical model concerning geostructural features, rainfall infiltration, and varying hydrological conditions was constructed. Initially, finite element (FE) groundwater seepage analyses were performed to evaluate the effect of water flow on stability in the dry and rainy seasons. The rainy season was simulated by vertical infiltration. Since the dewatering measures are of importance in open pit slope instability mitigation, pumping wells were designed to control water flow through the disturbed zone to improve the stability of the sector that can be triggered again with changing environmental conditions. The performance and organization of the pumping wells were also simulated in the FE model. This FE model was part of a dewatering plan. From this, the effect of the pumping rate from the wells on the stability of the sector was revealed. It was also found that there should be an increase in the pumping rate in the rainy season.

In this paper, finite element modelling is employed for simulating and analysing seepage and slope stability of earthfill dam via GeoStudio software. Two products are employed, which are SLOPE/W for slope stability and SEEP/W for seepage analysis. The behaviour of earthfill dam with four different types of sandy soils having different values of hydraulic conductivity (K) has been studied. Different upstream (US) slopes of 1:2, 1:2.5, 1:3 and 1:3.5 for the earthfill dam are simulated. The downstream (DS) slope is constant at 1:2. The results showed for all the four types of soils that when the US slope is increased, the amount of seepage from the dam increases and the factor of safety (F) decreases. For each US slope, when K (type of soil) increases, both seepage and F increase. Fine sand soil is associated with less seepage and less F. Sixteen equations are obtained to predict both seepage and F with respect to US slope for each type of soil and K of the soil for US slope. An experimental model for earthfill dam is constructed in the laboratory of hydraulics, Benha University to investigate the seepage of water through earthfill dams. It is concluded that seepage decreased when K decreased, and when the US slope for each type of soil decreased. The seepage increased when K increased for each US slope. Seven equations are obtained to predict seepage with respect to US slope for each type of soil, and K for each US slope.

In order to analyze the relationship between the configuration characteristics, variable mass permeability characteristics and the catastrophe mechanism of falling column process, The influence of the permeability was studied by diffraction instrument, And using the seepage test system of the fall column, The seepage instability process of variable mass broken rock mass is analyzed, The findings suggest that, The proportion of coarse particles accounted for 89.86%, Fine particles accounted for 10.14%, Broken rock particles is better, Low compression performance; The fall column, under strong hydrodynamic conditions, Due to its strong characteristics of migration and loss with water flow, It is easy to induce the subsidence column protrusion water disaster; As the ratio between coarse and fine aggregates increases, Porosity and permeability are both increased; When the axial displacement does not change, With the increasing circumference pressure, The permeability of the broken rock samples is decreasing; The fitting of the seepage velocity of the broken rock mass to the pore pressure gradient follows the Forchheimer relationship, The seepage of the broken rock mass belongs to the category of non-Darcy flow under the triaxial stress; The instability of the subsidence column fracture rock mass presents three seepage instability forms: initial seepage stage, seepage mutation stage and piping stage in different stages.

Post-mining dumps are a common sight in the industrial areas of Silesia (Poland). Despite several reclamation projects, many of them still constitute an unresolved problem. It is not only a matter of unaesthetic view – they often pose a threat to the environment and the people living nearby. Despite revitalization, some dumps are not properly maintained and are at the risk of slope failure. Such places require constant geodetic observation and stability control. In this article, the example of a dump located in the city of Gliwice was used to show the possibilities offered by the use of photogrammetry and unmanned aerial vehicles (UAV) for cyclic checks of the embankment condition. The current state of the dump and the results of interventions after two incidents of slope failure,were observed. The main slopes of the terrain surface and at the selected cross-sections were determined in two flight missions. The obtained geometrical data were used in the further numerical analysis. Finite Element Method model representing one of the escarpment cross-sectionswas built to estimate the factor of safety and determine the main mechanisms responsible for the failure. Elastic-perfectly plastic Coulomb-Mohr model was used to describe the behaviour of the minestone and the ‘ c – tan φ reduction’ – for calculation of the stability. The problem of reliable material properties’ estimation was emphasized. The analysis included the impact of seepage and total head difference on the slope stability. It was concluded that the rainfall intensity had a decisive influence on the instability of the dump.

High-pressure jet grouting pile is a kind of stratum reinforcement technology developed in recent years. Due to its characteristics of high solid strength, fast construction, low noise, safety and reliability, low cost, controllable reinforcement diameter, strong adaptability to stratum, and good reinforcement effect for soft soil, loose soil and water-rich stratum, high-pressure jet grouting pile technology has been more and more widely used in foundation treatment, water stop, and seepage prevention, tunnel lining and other fields in recent years. As a country with a relatively late development of underground construction engineering, Vietnam has little research on special geotechnical reinforcement technology, especially on special geotechnical reinforcement technology around urban underground construction engineering, especially on its theoretical analysis and practical application. Therefore, this thesis combines the Vietnam Trung Hoa tunnel project as an example, using the theoretical calculation formula and field monitoring measurement comparing the two methods, the high pressure jet grouting pile system research in Vietnam in the underground engineering reinforcement principle and application effect, get to the actual engineering design and construction has a guiding significance to the research, provides the reference for future similar projects. Finally, the application effect of high-pressure jet grouting pile in underground building reinforcement project is evaluated, which proves that high-pressure jet grouting pile has good applicability and economic benefit in underground building reinforcement project in Vietnam.