Assessment of destressing drilling efficiency using numerical methods: A case-study of Oktyabrsky deposit

2021 ◽  
pp. 26-31
Author(s):  
M. P. Sergunin ◽  
T. P. Darbinyan ◽  
T. S. Mushtekenov ◽  
V. V. Balandin
Keyword(s):  
Rock Mass ◽  
Theoretical Research ◽  
Labor Input ◽  
Efficiency Criterion ◽  
Strength And Deformation ◽  
Low Efficiency ◽  
Full Scale Tests ◽  
Time Required ◽  
Polar Division

Mineral mining in rockburst-hazardous conditions should involve various precautions in compliance with federal regulations and standards. One of the main methods to prevent rock bursts is destressing drilling. In this method, a yielding zone is artificially created. The strength and deformation characteristics in this zone differ from the same characteristics of enclosing rock mass, and redistribution of stresses takes place as a result. Efficiency of destressing drilling is estimated in terms of ore body S-2 in Komsomolsky Mine. The efficiency criterion is selected to be the safety factor of rock mass with and without destressing drilling. Low efficiency of destressing drilling means that this method is readily replaceable by the other techniques of lesser labor input, for example, by reduction in the rate of mining, or by seasoning of underground excavations for some time required for redistribution of stresses to take place. Based on the theoretical research and the conclusions drawn at NorNickel’s Polar Division, the full-scale tests are scheduled for the implementation in order to gradually abandon destessing drilling in rockburst-hazardous Talnakh and Oktyabrsky ore fields. The authors appreciate participation of V. P. Marysyuk from NorNickel’s Polar Division in this study.

scholarly journals Evaluating Life Cycle of Buildings Using an Integrated Approach Based on Quantitative-Qualitative and Simplified Best-Worst Methods (QQM-SBWM)

2021 ◽  
Vol 13 (8) ◽  
pp. 4487
Author(s):  
Maghsoud Amiri ◽  
Mohammad Hashemi-Tabatabaei ◽  
Mohammad Ghahremanloo ◽  
Mehdi Keshavarz-Ghorabaee ◽  
Edmundas Kazimieras Zavadskas ◽  
...  
Keyword(s):  
Life Cycle ◽  
Computer Software ◽  
Integrated Approach ◽  
Comfort Level ◽  
Combination Method ◽  
New Combination ◽  
Numerical Examples ◽  
Environmental Consequences ◽  
Time Required

Evaluating the life cycle of buildings is a valuable tool for assessing sustainability and analyzing environmental consequences throughout the construction operations of buildings. In this study, in order to determine the importance of building life cycle evaluation indicators, a new combination method was used based on a quantitative-qualitative method (QQM) and a simplified best-worst method (SBWM). The SBWM method was used because it simplifies BWM calculations and does not require solving complex mathematical models. Reducing the time required to perform calculations and eliminating the need for complicated computer software are among the advantages of the proposed method. The QQM method has also been used due to its ability to evaluate quantitative and qualitative criteria simultaneously. The feasibility and applicability of the SBWM were examined using three numerical examples and a case study, and the results were evaluated. The results of the case study showed that the criteria of the estimated cost, comfort level, and basic floor area were, in order, the most important criteria among the others. The results of the numerical examples and the case study showed that the proposed method had a lower total deviation (TD) compared to the basic BWM. Sensitivity analysis results also confirmed that the proposed approach has a high degree of robustness for ranking and weighting criteria.

scholarly journals A Model for Developing Existing Ports Considering Economic Impact and Network Connectivity

2021 ◽  
Vol 13 (7) ◽  
pp. 3705
Author(s):  
Veterina Nosadila Riaventin ◽  
Sofyan Dwi Cahyo ◽  
Ivan Kristianto Singgih
Keyword(s):  
Network Connectivity ◽  
Economic Consequences ◽  
Real Problem ◽  
Container Transportation ◽  
Container Ports ◽  
Investment Priority ◽  
Time Required ◽  
Transportation Flows ◽  
Port Clusters

This study discusses the problem of determining which container port should be developed within an existing network and when this should be carried out. A case study of Indonesia’s port network is presented, where several new ports are to be improved to ensure smooth interisland transportation flows of goods. The effects of the investment on economic consequences and increased network connectivity are assessed. When improving the ports, we consider that the available budget limits the investment. The network connectivity is evaluated by considering the number of reachable ports from the developed ports or transportation time required from other ports within the same port cluster. Based on our knowledge, our study is the first one that discusses the investment problem in multiple container ports under single management, as well as its effects regarding the increase in container flows. The problem is introduced and three mathematical models are proposed and used to solve a real problem. The results show that different models have different improved aspects of container transportation flows—e.g., a balanced improvement of the whole port network (Model 2) and appropriate investment priority for port clusters (Model 3).

scholarly journals Exploring the relationship between corporate social responsibility actions and employee retention: A human resource management perspective

2021 ◽  
pp. 1-13
Author(s):  
Hajar Boutmaghzoute ◽  
Karim Moustaghfir
Keyword(s):  
Job Satisfaction ◽  
Organizational Identification ◽  
Employee Retention ◽  
Employee Commitment ◽  
Theoretical Framework ◽  
Theoretical Research ◽  
Future Research ◽  
Behavioral Factors ◽  
The Relationship

BACKGROUND: This study builds on the little guidance in the existing literature to analyze the relationship between employee-oriented CSR actions and employee retention in a business context, while using Freeman stakeholders’ model as a theoretical research framework. This research also aims to shed light on significant behavioral factors facilitating the relationship between CSR endeavors and turnover rate. OBJECTIVE: This paper builds on the existing research gap in the literature and suggests that behavioral factors, including job satisfaction, organizational identification, and motivation facilitate the relationship between employee-oriented CSR actions and employee retention, which contributes to laying the foundations of a theoretical framework that has the potential to advance both theoretical and practitioner debates and disentangle the complexity of such a relationship, while offering strategically-focused development venues in CSR and HRM fields. METHODS: This research uses a single case study design to ensure an in-depth and detailed analysis of the phenomenon under scrutiny, while relying on a triangulation methodology for data collection, including a questionnaire used as exploratory approach, interviews to generate explanatory data, and archival data to bring confirmatory insights. Data analysis followed the procedures of a deductive approach. RESULTS: The research results show a positive relationship between employee-oriented CSR actions and employee retention, while demonstrating the facilitating role of job satisfaction, organizational identification, and motivation in moderating such a relationship. The findings also stress the importance of framing CSR interventions within the organization’s strategy and goals, while ensuring employee participation in such decision making processes to maximize the effect of CSR interventions on employee commitment and reduce turnover. CONCLUSIONS: This research has the potential to better clarify the nature of the relationship involving CSR interventions, from an employee perspective, retention, and turnover, while laying the foundations of a theoretical framework linking such constructs and other behavioral factors that underpin and support such a relationship. Building on the study’s findings and assumptions, future research is needed to gain a more comprehensive understanding of how HR-related CSR actions affect behavioral performance dimensions, resulting in employee commitment and retention. Future research should also consider multiple case study, multicultural, and ethnographic approaches for the sake of generalizability and theory building.

Destress blasting in deep mines of NorNickel’s Polar Division

2021 ◽  
pp. 32-36
Author(s):  
G. V. Sabyanin ◽  
S. Yu. Shilenko ◽  
A. V. Trofimov ◽  
A. P. Kirkin
Keyword(s):  
Horizontal Plane ◽  
Large Diameter ◽  
Geophysical Methods ◽  
Full Scale ◽  
Underground Mines ◽  
Destress Blasting ◽  
Drilling Cost ◽  
Full Scale Tests ◽  
Polar Division ◽  
Oktyabrsky Mine

Talnakh and Oktyabrsky ore fields are estimated as rockburst-hazardous starting from the depth of 700 m downward according to safety rules. This means that mining is only permitted within certain protected zones. At the present times, such protected zones are generated in underground mines by means of the large-diameter destressing drilling. Despite proved efficiency, the high cost and large amount of the destressing drilling are the grave faults of this approach. Aiming to save drilling cost, it is proposed to make rock mass rockburst-unhazardous using destress blasting. This article gives a brief description of the destress blasting mechanism. This method has been effectively used in relaxation of pillars from stresses before extraction of the reserves from the pillars both in Russia and abroad. In Oktyabrsky Mine stress relaxation of pillars was implemented by slotting, and the drilling and blasting data were available. This study proposes to destress rock masses by means of directional destress fracturing in horizontal plane through blasting of decked charges of special design. The initial parameters for destress blasting using holes with diameters of 76 and 130 mm are determined. The charge design aimed to ensure a zone of fractures in the horizontal plane, at minimized vertical fracturing is described. This information can be used in planning of full-scale tests to refine parameters and application ranges of the method. For the full-scale tests, it is suggested to undertake destress blasting at different blast patterns on different test sites, and to compare the results with the current destressing method (destressing drilling). Efficiency can be proved using geomechanical and geophysical methods. The authors appreciate participation of V. P. Marysyuk and T. P. Darbinyan from NorNickel’s Polar Division in this study.

Implementation of InfraRed Thermographic surveys in complex coastal areas: the case study of Polignano a Mare (southern Italy)

2021 ◽  
Author(s):  
Lidia Loiotine ◽  
Marco La Salandra ◽  
Gioacchino Francesco Andriani ◽  
Eliana Apicella ◽  
Michel Jaboyedoff ◽  
...  
Keyword(s):  
Rock Mass ◽  
Structure From Motion ◽  
Southern Italy ◽  
Thermal Imager ◽  
Rock Masses ◽  
Field Surveys ◽  
Thermal Images ◽  
Thermal Anomalies ◽  
Rock Face

<p><em>InfraRed Thermography</em> (IRT) spread quickly during the second half of the 20<sup>th</sup> century in the military, industrial and medical fields. This technique is at present widely used in the building sector to detect structural defects and energy losses. Being a non-destructive diagnostic technique, IRT was also introduced in the Earth Sciences, especially in the volcanology and environmental fields, yet its application for geostructural surveys is of recent development. Indeed, the acquisition of thermal images on rock masses could be an efficient tool for identifying fractures and voids, thus detecting signs of potential failures.<br>Further tests of thermal cameras on rock masses could help to evaluate the applicability, advantages and limits of the IRT technology for characterizing rock masses in different geological settings.<br>We present some results of IRT surveys carried out in the coastal area of Polignano a Mare (southern Italy), and their correlation with other remote sensing techniques (i.e. <em>Terrestrial Laser Scanning</em> and <em>Structure from Motion</em>). The case study (<em>Lama Monachile</em>) is represented by a 20 m-high cliff made up of Plio-Pleistocene calcarenites overlying Cretaceous limestones. Conjugate fracture systems, karst features, folds and faults, were detected in the rock mass during field surveys. In addition, dense vegetation and anthropogenic elements, which at places modified the natural setting of the rock mass, represent relevant disturbances for the characterization of the rock mass. In this context, IRT surveys were added to the other techniques, aimed at detecting the major discontinuities and fractured zones, based on potential thermal anomalies. <br>IRT surveys were carried out in December 2020 on the east side of the rock mass at <em>Lama Monachile</em> site. Thermal images were acquired every 20 minutes for 24 hours by means of a FLIR T-660 thermal imager mounted on a fixed tripod. Ambient air temperature and relative humidity were measured during the acquisition with a pocketsize thermo-hydrometer. A reflective paper was placed at the base of the cliff to measure the reflected apparent temperature. In addition, three thermocouple sensors were fixed to the different lithologic units of the rock face. These parameters, together with the distance between the FLIR T-660 and the rock face, were used in order to calibrate the thermal imager and correct the apparent temperatures recorded by the device, during the post-processing phase. Successively, vertical profiles showing the temperature of the rock face over time were extracted from the thermograms. Thermal anomalies were correlated with stratigraphic and Geological Strength Index profiles, obtained by means of field surveys and Structure from Motion techniques. The presence of fracture and voids in the rock mass was also investigated.</p>

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