This paper presents the technological and structural design solution of a tunnel-shaped underpass constructed for the coal conveyor belt of a combined transport system, serving the Roof Exploitation Zone of the Gacko - Central Field open-pit coal mine. The underpass has a clear opening of 6.1 meters in width and 2.5 meters in height and is positioned at an azimuth of 140 degrees. It is integrated beneath a haul road intended for ultra-heavy-duty mining trucks, specifically BELAZ trucks with a payload capacity of 110 tonnes, used for overburden transport. The underpass is equipped with wing walls on all sides, to ensure structural stability and seamless integration with the surrounding terrain. The solution ensures uninterrupted operation of the conveyor system while maintaining the safety and functionality of the haul road for continuous mining operations.
In many countries, coal plays a primary role in ensuring energy supply security. As a competitive fuel, it directly affects the economic value in the production of steel, cement, and, most importantly, in the generation of electricity and heat. A diverse energy mix with controlled use of coal can be part of a strategy that reduces risk and supports sustainable economic growth. Conventional energy generation in thermal power plants, including nuclear, coal, lignite, and gas-fired plants, requires sustainability and will remain necessary in the future. Today, new renewable energy sources, primarily wind turbines and solar photovoltaic systems, are gaining importance, but they still require reliable backup from conventional sources. Space is increasingly being created for the integration of renewable energy sources, given the flexibility and reliability of coal and lignite-based power generation. A key prerequisite for future electricity production in Europe lies in utilizing a broad spectrum of energy sources to minimize supply risks, maximize reliability, and achieve further progress in environmental and climate protection.
This paper examines the optimization of oil production using reciprocating pumps through corrective adjustment of operating parameters. Considering the challenges posed by Industry 4.0, such as increased demand and the need for more efficient resource use, the study highlights the importance of applying modern technologies and methods for improving production processes. It focuses on the implementation of smart sucker rod pumps (SRP) equipped with Internet of Things (IoT) technologies that enable real-time data collection and analysis. Through the analysis of several wells, the study demonstrates how changes in pump speed affect production dynamics, volumetric efficiency, and energy consumption. The results showed that reducing the number of pump strokes led to improved efficiency and lower energy costs, further increasing the sustainability and profitability of oil production.
In practice, a number of methods have been developed for calculating the settlement of shallow foundations on sand, but in general it can be said that there is no standardized calculation method. The practice has shown that when calculating the settlement of mat foundation of large dimensions, significantly larger settlements are obtained compared to the measured ones. This may indicate certain shortcomings when using the usual empirical relations for settlement calculation. This work presents the most commonly used semi-empirical methods for calculating the foundation settlement on sandy soils, and it analyzes the results obtained using different approaches (Schmertmann et al., 1970, 1978; Schultze and Sherif, 1973; Janbu et al., 1956), including the numerical simulations in the Settle3 program, which combines the simplicity of one-dimensional settlement analysis with the visualization capabilities of more modern three-dimensional programs. The analysis was carried out on one specific facility that was built in Novi Sad. During its construction, geodetic monitoring of settlement was performed, which enabled a comparison between the calculated and measured values.
Maintaining the open pit slopes in a stable condition requires compliance between the geometrical parameters of the open pit on one side and the pit-technical conditions, physical-mechanical properties of the rocks and hydrogeological properties of the deposit on the other side. When the underground activity is located below an open pit, deformation of the open pit slopes can be expected as a result of subsidence caused by the underground mining. For an adequate analysis of the stress-strain states in the massif, it is essential to consider the partial relaxation of the primary stresses in the excavation. Numerical analysis simulates the progress of mining works and stress changes and deformations in the vicinity of the underground room, the amount of subsidence on the ground surface depending on the chosen method of mechanized excavation, i.e. the impact on the open pit slopes. Numerous examples in the world provide a clear warning regarding the possible impact of underground works at the open pit. Analysis the impact of dimensions and spatial position of the wide front panel and column-chamber excavation on the stress-strain state, i.e. stability of the open pit slope, was done on the example of the "Gacko" open pit mine.
