Preliminary assessment of roadheaders efficiency based on empirical methods and index of equivalent rock strength

Purpose. The choice of a proper roadheader is a critically important step in planning of a project or some of its stages. Nowadays various manufacturers produce numerous models of these vehicles, hence it is unreasonable to conduct a thorough analysis of each model’s parameters in terms of their adequacy for the successful implementation of the project. Therefore, it is necessary to develop quite simple and easy-to-use assessment of roadheaders efficiency at the project preliminary stages. Methods. The widely used model of the Colorado School of Mines based on numerous laboratory tests has been applied as the basic model for determining theoretical efficiency of rock mass destruction. Since domestic scientists are accustomed to using rock strength parameters, which differ from values σc and σt accepted everywhere (including Russia), we represented dependencies that allow to convert values of some indicators to the values of other indicators. Findings. Calculating the efficiency of roadheaders’ use for each geological section with homogeneous rock can take unreasonably long time. Thus, it is necessary to have a simple integrated strength index for the whole excavation or even enterprise, which can be interpreted through the generally accepted values such as the uniaxial compressive strength σc and tensile strength σt. Jointing of rocks is also an important parameter in a feasibility study of roadheaders’ efficiency. Originality. The equivalent rock strength index was applied as a simple integrated strength index for the whole excavation. This parameter is established on the basis of integrated assessment index of mining operations complexity, which comprises the sum of the uniaxial compressive strength σc and rock jointing for the whole excavation or even mining enterprise. Practical implications. The results of this paper can serve as a preliminary scientifically grounded method of selecting equipment for a particular project in mining industry or underground construction by the efficiency criterion. Its main advantage is simplicity and clarity. However, it should be noted that this method should not be applied at the stage of the project final feasibility study, especially without considering other production factors (compatibility with other equipment, availability of the personnel with adequate qualification for operation and maintenance of the chosen machine etc.).Мета. Вибір конкретного прохідницького комбайна є критично важливим кроком у плануванні робіт по проекту або будь-якого з його етапів. При цьому номенклатура машин, що випускаються різними виробниками в даний час, надзвичайно велика, що робить недоцільним ретельний аналіз кожної моделі комбайна з точки зору його адекватності необхідним для успішної реалізації проекту параметрам. Таким чином, виникає необхідність у досить простій і швидко проводимій попередній оцінці машин уже на передпроектній стадії. Методика. В якості основної моделі для визначення теоретичної продуктивності руйнування гірського масиву була використана методика Колорадського гірничого університету, яка заснована на численних лабораторних випробуваннях і пройшла широку апробацію на практиці. Для вітчизняних фахівців, що звикли до використання у своїй діяльності міцнісних показників гірських порід, що відрізняються від повсюдно (у тому числі в Росії) прийнятих величин σст і σр представлені залежності, що дозволяють проводити перерахунок значень одних показників до значень інших показників. Результати. Обчислення ефективності використання прохідницьких комбайнів для кожної геологічної ділянки з однорідними породами може зайняти невиправдано багато часу. У зв’язку з чим виникає необхідність у простому, інтегральному для всієї виробки або гірничого підприємства, показника міцності, який може бути інтерпретований через загальноприйняті величини – межу міцності на стиск σст і межу міцності на розтяг σр. Також важливим параметром у техніко-економічному обґрунтуванні ефективності прохідницьких комбайнів є тріщинуватість гірських порід. Наукова новизна. В якості найпростішого інтегрального показника міцності порід по всій виробці використовувався показник еквівалентної міцності гірських порід. Цей параметр визначається на основі показника інтегральної оцінки складності гірничопрохідницьких робіт, заснованої на підсумовуванні межі міцності на стиск σст і тріщинуватості гірських порід по всій виробці або навіть гірничому підприємству. Практична значимість. Отримані результати можуть слугувати в якості попереднього науково обґрунтованого способу відбору техніки для конкретного проекту в гірничодобувній галузі або підземному будівництві за критерієм продуктивності. Її основною перевагою є простота і зрозумілість. Однак варто зазначити, що розглянуту методику не слід застосовувати на етапі остаточного техніко-економічного обґрунтування проекту, тим більше у відриві від інших виробничих факторів (сумісність з іншим обладнанням, наявність персоналу з необхідною для експлуатації та обслуговування обраної машини кваліфікацією і т.д.).Цель. Выбор конкретного проходческого комбайна является критически важным шагом в планировании работ по проекту или какому-либо из его этапов. При этом номенклатура машин, выпускаемых различными производителями в настоящее время, необычайно велика, что делает нецелесообразным тщательный анализ каждой модели комбайна с точки зрения его адекватности требуемым для успешной реализации проекта параметрам. Таким образом, возникает необходимость в достаточно простой и быстро проводимой предварительной оценке машин уже на предпроектной стадии. Методика. В качестве основной модели для определения теоретической производительности разрушения горного массива была использована методика Колорадского горного университета, которая основана на многочисленных лабораторных испытаниях и прошла широкую апробацию на практике. Для отечественных специалистов, привыкших к использованию в своей деятельности прочностных показателей горных пород, отличающихся от повсеместно (в том числе в России) принятых величин σсж и σр представлены зависимости, позволяющие производить перерасчет значений одних показателей к значениям других показателей. Результаты. Вычисление эффективности использования проходческих комбайнов для каждого геологического участка с однородными породами может занять неоправданно много времени. В связи с чем возникает необходимость в простом, интегральном для всей выработки или горного предприятия, прочностном показателе, который может быть интерпретирован через общепринятые величины – предел прочности на сжатие σсж и предел прочности на растяжение σр. Также важным параметром в технико-экономическом обосновании эффективности проходческих комбайнов является трещиноватость горных пород. Научная новизна. В качестве простейшего интегрального показателя прочности пород по всей выработке использовался показатель эквивалентной прочности горных пород. Этот параметр определяется на основе показателя интегральной оценки сложности горнопроходческих работ, основанной на суммировании предела прочности на сжатие σсж и трещиноватости горных пород по всей выработке или даже горному предприятию. Практическая значимость. Полученные результаты могут служить в качестве предварительного научно обоснованного способа отбора техники для конкретного проекта в горнодобывающей отрасли или подземном строительстве по критерию производительности. Ее основным достоинством является простота и понятность. Однако стоит отметить, что рассмотренную методику не следует применять на этапе окончательного технико-экономического обоснования проекта, тем более в отрыве от других производственных факторов (совместимость с прочим оборудованием, наличие персонала с необходимой для эксплуатации и обслуживания выбираемой машины квалификацией и т.д.).We wish to confirm that there has been no significant financial support for this work that could have influenced its outcome

Методика предварительной оценки технико-экономического эффекта от применения проходческого комбайна на проекте

Приведена методика для предварительной оценки технико- экономического эффекта от применения проходческого комбайна на проекте, основанная на показателях эквивалентной прочности горных пород и интегральной оценки сложности походки горной выработки. Для указанной методики приведен пример расчета с обоснованием выбора комбайна для конкретного проекта

Cutting force component-based rock differentiation utilising machine learning

This dissertation evaluates the possibilities and limitations of rock type identification in rock cutting with conical picks. For this, machine learning in conjunction with features derived from high frequency cutting force measurements is used. On the basis of linear cutting experiments, it is shown that boundary layers can be identified with a precision of less than 3.7 cm when using the developed programme routine. It is further shown that rocks weakened by cracks can be well identified and that anisotropic rock behaviour may be problematic to the classification success. In a case study, it is shown that the supervised algorithms artificial neural network and distributed random forest perform relatively well while unsupervised k-means clustering provides limited accuracies for complex situations. The 3d-results are visualised in a web app. The results suggest that a possible rock classification system can achieve good results—that are robust to changes in the cutting parameters when using the proposed evaluation methods.:1 Introduction...1 2 Cutting Excavation with Conical Picks...5 2.1 Cutting Process...8 2.1.2 Cutting Parameters...11 2.1.3 Influences of Rock Mechanical Properties...17 2.1.4 Influences of the Rock Mass...23 2.2 Ratios of Cutting Force Components...24 3 State of the Art...29 3.1 Data Analysis in Rock Cutting Research...29 3.2 Rock Classification Systems...32 3.2.1 MWC – Measure-While-Cutting...32 3.2.2 MWD – Measuring-While-Drilling...34 3.2.3 Automated Profiling During Cutting...35 3.2.4 Wear Monitoring...36 3.3 Machine learning for Rock Classification...36 4 Problem Statement and Justification of Topic...38 5 Material and Methods...40 5.1 Rock Cutting Equipment...40 5.2 Software & PC...42 5.3 Samples and Rock Cutting Parameters...43 5.3.1 Sample Sites...43 5.3.2 Experiment CO – Zoned Concrete...45 5.3.3 Experiment GN – Anisotropic Rock Gneiss...47 5.3.4 Experiment GR – Uncracked and Cracked Granite...49 5.3.5 Case Study PB and FBA – Lead-Zinc and Fluorite-Barite Ores...50 5.4 Data Processing...53 5.5 Force Component Ratio Calculation...54 5.6 Procedural Selection of Features...57 5.7 Image-Based Referencing and Rock Boundary Modelling...60 5.8 Block Modelling and Gridding...61 5.9 Correlation Analysis...63 5.10 Regression Analysis of Effect...64 5.11 Machine Learning...65 5.11.2 K-Means Algorithm...66 5.11.3 Artificial Neural Networks...67 5.11.4 Distributed Random Forest...70 5.11.5 Classification Success...72 5.11.6 Boundary Layer Recognition Precision...73 5.12 Machine Learning Case Study...74 6 Results...75 6.1 CO – Zoned Concrete...75 6.1.1 Descriptive Statistics...75 6.1.2 Procedural Evaluation...76 6.1.3 Correlation of the Covariates...78 6.1.4 K-Means Cluster Analysis...79 6.2 GN – Foliated Gneiss...85 6.2.1 Cutting Forces...86 6.2.2 Regression Analysis of Effect...88 6.2.3 Details Irregular Behaviour...90 6.2.4 Interpretation of Anisotropic Behaviour...92 6.2.5 Force Component Ratios...92 6.2.6 Summary and Interpretations of Results...93 6.3 CR – Cracked Granite...94 6.3.1 Force Component Results...94 6.3.2 Spatial Analysis...97 6.3.3 Error Analysis...99 6.3.4 Summary...100 6.4 Case Study...100 6.4.1 Feature Distribution in Block Models...101 6.4.2 Distributed Random Forest...105 6.4.3 Artificial Neural Network...107 6.4.4 K-Means...110 6.4.5 Training Data Required...112 7 Discussion...114 7.1 Critical Discussion of Experimental Results...114 7.1.1 Experiment CO...114 7.1.2 Experiment GN...115 7.1.3 Experiment GR...116 7.1.4 Case Study...116 7.1.5 Additional Outcomes...117 7.2 Comparison of Machine Learning Algorithms...118 7.2.1 K-Means...118 7.2.2 Artificial Neural Networks and Distributed Random Forest...119 7.2.3 Summary...120 7.3 Considerations Towards Sensor System...121 7.3.1 Force Vectors and Data Acquisition Rate...121 7.3.2 Sensor Types...122 7.3.3 Computation Speed...123 8 Summary and Outlook...125 References...128 Annex A Fields of Application of Conical Tools...145 Annex B Supplements Cutting and Rock Parameters...149 Annex C Details Topic-Analysis Rock Cutting Publications...155 Annex D Details Patent Analysis...157 Annex E Details Rock Cutting Unit HSX-1000-50...161 Annex F Details Used Pick...162 Annex G Error Analysis Cutting Experiments...163 Annex H Details Photographic Modelling...166 Annex I Laser Offset...168 Annex J Supplements Experiment CO...169 Annex K Supplements Experiment GN...187 Annex L Supplements Experiment GR...191 Annex M Preliminary Artificial Neural Network Training...195 Annex N Supplements Case Study (CD)...201 Annex O R-Codes (CD)...203 Annex P Supplements Rock Mechanical Tests (CD)...204Die Dissertation evaluiert Möglichkeiten und Grenzen der Gebirgserkennung bei der schneidenden Gewinnung von Festgesteinen mit Rundschaftmeißeln unter Nutzung maschinellen Lernens – in Verbindung mit aus hochaufgelösten Schnittkraftmessungen abgeleiteten Kennwerten. Es wird auf linearen Schneidversuchen aufbauend gezeigt, dass Schichtgrenzen mit Genauigkeiten unter 3,7 cm identifiziert werden können. Ferner wird gezeigt, dass durch Risse geschwächte Gesteine gut identifiziert werden können und dass anisotropes Gesteinsverhalten möglicherweise problematisch auf den Klassifizierungserfolg wirkt. In einer Fallstudie wird gezeigt, dass die überwachten Algorithmen Künstliches Neurales Netz und Distributed Random Forest teils sehr gute Ergebnisse erzielen und unüberwachtes k-means-Clustering begrenzte Genauigkeiten für komplexe Situationen liefert. Die Ergebnisse werden in einer Web-App visualisiert. Aus den Ergebnissen wird abgeleitet, dass ein mögliches Sensorsystem mit den vorgeschlagenen Auswerteroutinen gute Ergebnisse erzielen kann, die gleichzeitig robust gegen Änderungen der Schneidparameter sind.:1 Introduction...1 2 Cutting Excavation with Conical Picks...5 2.1 Cutting Process...8 2.1.2 Cutting Parameters...11 2.1.3 Influences of Rock Mechanical Properties...17 2.1.4 Influences of the Rock Mass...23 2.2 Ratios of Cutting Force Components...24 3 State of the Art...29 3.1 Data Analysis in Rock Cutting Research...29 3.2 Rock Classification Systems...32 3.2.1 MWC – Measure-While-Cutting...32 3.2.2 MWD – Measuring-While-Drilling...34 3.2.3 Automated Profiling During Cutting...35 3.2.4 Wear Monitoring...36 3.3 Machine learning for Rock Classification...36 4 Problem Statement and Justification of Topic...38 5 Material and Methods...40 5.1 Rock Cutting Equipment...40 5.2 Software & PC...42 5.3 Samples and Rock Cutting Parameters...43 5.3.1 Sample Sites...43 5.3.2 Experiment CO – Zoned Concrete...45 5.3.3 Experiment GN – Anisotropic Rock Gneiss...47 5.3.4 Experiment GR – Uncracked and Cracked Granite...49 5.3.5 Case Study PB and FBA – Lead-Zinc and Fluorite-Barite Ores...50 5.4 Data Processing...53 5.5 Force Component Ratio Calculation...54 5.6 Procedural Selection of Features...57 5.7 Image-Based Referencing and Rock Boundary Modelling...60 5.8 Block Modelling and Gridding...61 5.9 Correlation Analysis...63 5.10 Regression Analysis of Effect...64 5.11 Machine Learning...65 5.11.2 K-Means Algorithm...66 5.11.3 Artificial Neural Networks...67 5.11.4 Distributed Random Forest...70 5.11.5 Classification Success...72 5.11.6 Boundary Layer Recognition Precision...73 5.12 Machine Learning Case Study...74 6 Results...75 6.1 CO – Zoned Concrete...75 6.1.1 Descriptive Statistics...75 6.1.2 Procedural Evaluation...76 6.1.3 Correlation of the Covariates...78 6.1.4 K-Means Cluster Analysis...79 6.2 GN – Foliated Gneiss...85 6.2.1 Cutting Forces...86 6.2.2 Regression Analysis of Effect...88 6.2.3 Details Irregular Behaviour...90 6.2.4 Interpretation of Anisotropic Behaviour...92 6.2.5 Force Component Ratios...92 6.2.6 Summary and Interpretations of Results...93 6.3 CR – Cracked Granite...94 6.3.1 Force Component Results...94 6.3.2 Spatial Analysis...97 6.3.3 Error Analysis...99 6.3.4 Summary...100 6.4 Case Study...100 6.4.1 Feature Distribution in Block Models...101 6.4.2 Distributed Random Forest...105 6.4.3 Artificial Neural Network...107 6.4.4 K-Means...110 6.4.5 Training Data Required...112 7 Discussion...114 7.1 Critical Discussion of Experimental Results...114 7.1.1 Experiment CO...114 7.1.2 Experiment GN...115 7.1.3 Experiment GR...116 7.1.4 Case Study...116 7.1.5 Additional Outcomes...117 7.2 Comparison of Machine Learning Algorithms...118 7.2.1 K-Means...118 7.2.2 Artificial Neural Networks and Distributed Random Forest...119 7.2.3 Summary...120 7.3 Considerations Towards Sensor System...121 7.3.1 Force Vectors and Data Acquisition Rate...121 7.3.2 Sensor Types...122 7.3.3 Computation Speed...123 8 Summary and Outlook...125 References...128 Annex A Fields of Application of Conical Tools...145 Annex B Supplements Cutting and Rock Parameters...149 Annex C Details Topic-Analysis Rock Cutting Publications...155 Annex D Details Patent Analysis...157 Annex E Details Rock Cutting Unit HSX-1000-50...161 Annex F Details Used Pick...162 Annex G Error Analysis Cutting Experiments...163 Annex H Details Photographic Modelling...166 Annex I Laser Offset...168 Annex J Supplements Experiment CO...169 Annex K Supplements Experiment GN...187 Annex L Supplements Experiment GR...191 Annex M Preliminary Artificial Neural Network Training...195 Annex N Supplements Case Study (CD)...201 Annex O R-Codes (CD)...203 Annex P Supplements Rock Mechanical Tests (CD)...20

PREDVIĐANJE SVOJSTAVA HIDRAULIČKOGA RAZBIJAČA STIJENA KOD NJIHOVA ISKAPANJA

The demand for the usage of hydraulic rock breakers in excavating rock masses has increased recently for environmental and economic reasons. The conventional method (i.e., drill and blasting technique) has many restrictions due to environmental aspects. In this paper, we propose a methodology for the prediction of the performance of hydraulic rock breakers in the excavation of a rock mass. The case study area is located in Northwest Egypt on the shoreline of the Mediterranean Sea. Extensive site investigation was implemented using exploration boreholes showing that the majority of the site is limestone with lenses of sands. Based on the collected rock properties, mapping of both the rock quality (RQD) and the uniaxial compressive strength (UCS) for the rock mass was conducted. Such mapping of the mechanical properties helps in the zoning of a rock mass and grouping the similar rock zones of nearly matched properties. Due to economic and machinery availability concerns, this study focuses on very small, small, and medium capacity hydraulic breakers. For each type of rock breaker, calculations of the net breaking rate (NBR) are implemented for each group of the rock with similar properties. The challenge of this methodology is that the excavation of the rock mass shall be implemented in a very limited time frame (only one year ≈ 300 workdays). Therefore, two scenarios of light-duty and medium rock breakers are applied providing the number of machines required with specifications and working days. The first scenario is assigned to medium duty machines, while the second scenario concerns very small to small rock breakers. In general, such a sequence could be adopted for other cases with different rock mass properties, hydraulic breakers specifications and any desired time frame.Potreba uporabe hidrauličkoga razbijača kod pridobivanja stijena postaje sve veća zbog očuvanja okoliša i iz ekonomskih razloga. Konvencionalne metode (poput bušenja i miniranja) imaju mnogo ograničenja s obzirom na njihov utjecaj na okoliš. Ovdje je predložena metodologija kojom se predviđaju svojstva hidrauličkoga razbijača stijena. Kao testno područje odabrano je smjestište u sjeverozapadnome Egiptu, na obali Sredozemnoga mora. Načinjena su brojna istraživanja bušenjem, a rezultati su pokazali kako je u najvećemu dijelu stijenska masa vapnenac s lećama pijeska. Temeljem istraženih svojstava stijena kartirane su kvaliteta stijenske mase i jednoosna tlačna čvrstoća. Rezultati su pomogli u zoniranju stijenske mase i svrstavanju stijena u skupine sličnih svojstava. Zbog ekonomičnosti i dostupnih strojeva istraživanje se odnosilo na razbijače vrlo maloga, maloga i srednjega kapaciteta. Za svaku vrstu izračunan je stvarni iznos lomljenja u pojedinačnim skupinama stijena. Pri tomu je izazov predstavljao vremenski ograničeno iskopavanje/lomljenje koje se obavljalo tijekom 1 godine, tj. 300 radnih dana. Razrađena su dva scenarija, prvi za strojeve srednjega i drugi za one maloga kapaciteta s potrebnim brojem jedinica i radnih dana za svaki. Prikazani algoritam može se primijeniti za druge slučajeve, s različitim svojstvima stijena, strojeva i vremenskoga okvira

Thermal analysis of wood-steel hybrid construction

Main goal of this work is to present a numerical model to study the thermal necrosis due a dental drilling process, with and without water irrigation. Also an experimental methodology is used to measure the thermal occurrence in a pig mandible. Motivation, the assessment of bone damage, using the temperature criterion (above 55ºC

Volume II: Mining Innovation

Contemporary exploitation of natural raw materials by borehole, opencast, underground, seabed, and anthropogenic deposits is closely related to, among others, geomechanics, automation, computer science, and numerical methods. More and more often, individual fields of science coexist and complement each other, contributing to lowering exploitation costs, increasing production, and reduction of the time needed to prepare and exploit the deposit. The continuous development of national economies is related to the increasing demand for energy, metal, rock, and chemical resources. Very often, exploitation is carried out in complex geological and mining conditions, which are accompanied by natural hazards such as rock bursts, methane, coal dust explosion, spontaneous combustion, water, gas, and temperature. In order to conduct a safe and economically justified operation, modern construction materials are being used more and more often in mining to support excavations, both under static and dynamic loads. The individual production stages are supported by specialized computer programs for cutting the deposit as well as for modeling the behavior of the rock mass after excavation in it. Currently, the automation and monitoring of the mining works play a very important role, which will significantly contribute to the improvement of safety conditions. In this Special Issue of Energies, we focus on innovative laboratory, numerical, and industrial research that has a positive impact on the development of safety and exploitation in mining

FCC-ee: The Lepton Collider: Future Circular Collider Conceptual Design Report Volume 2

Overview of the research program of a future lepton collider

FCC-ee: The Lepton Collider: Future Circular Collider Conceptual Design Report Volume 2

In response to the 2013 Update of the European Strategy for Particle Physics, the Future Circular Collider (FCC) study was launched, as an international collaboration hosted by CERN. This study covers a highest-luminosity high-energy lepton collider (FCC-ee) and an energy-frontier hadron collider (FCC-hh), which could, successively, be installed in the same 100 km tunnel. The scientific capabilities of the integrated FCC programme would serve the worldwide community throughout the 21st century. The FCC study also investigates an LHC energy upgrade, using FCC-hh technology. This document constitutes the second volume of the FCC Conceptual Design Report, devoted to the electron-positron collider FCC-ee. After summarizing the physics discovery opportunities, it presents the accelerator design, performance reach, a staged operation scenario, the underlying technologies, civil engineering, technical infrastructure, and an implementation plan. FCC-ee can be built with today’s technology. Most of the FCC-ee infrastructure could be reused for FCC-hh. Combining concepts from past and present lepton colliders and adding a few novel elements, the FCC-ee design promises outstandingly high luminosity. This will make the FCC-ee a unique precision instrument to study the heaviest known particles (Z, W and H bosons and the top quark), offering great direct and indirect sensitivity to new physics

The Large Hadron–Electron Collider at the HL-LHC

Se incluye contenido parcial de los autores, (contiene más de 300 autores)The Large Hadron–Electron Collider (LHeC) is designed to move the field of deep inelastic scattering (DIS) to the energy and intensity frontier of particle physics. Exploiting energy-recovery technology, it collides a novel, intense electron beam with a proton or ion beam from the High-Luminosity Large Hadron Collider (HL-LHC). The accelerator and interaction region are designed for concurrent electron–proton and proton–proton operations. This report represents an update to the LHeC’s conceptual design report (CDR), published in 2012. It comprises new results on the parton structure of the proton and heavier nuclei, QCD dynamics, and electroweak and top-quark physics. It is shown how the LHeC will open a new chapter of nuclear particle physics by extending the accessible kinematic range of lepton–nucleus scattering by several orders of magnitude. Due to its enhanced luminosity and large energy and the cleanliness of the final hadronic states, the LHeC has a strong Higgs physics programme and its own discovery potential for new physics. Building on the 2012 CDR, this report contains a detailed updated design for the energy-recovery electron linac (ERL), including a new lattice, magnet and superconducting radio-frequency technology, and further components. Challenges of energy recovery are described, and the lower-energy, high-current, three-turn ERL facility, PERLE at Orsay, is presented, which uses the LHeC characteristics serving as a development facility for the design and operation of the LHeC. An updated detector design is presented corresponding to the acceptance, resolution, and calibration goals that arise from the Higgs and parton-density-function physics programmes. This paper also presents novel results for the Future Circular Collider in electron–hadron (FCC-eh) mode, which utilises the same ERL technology to further extend the reach of DIS to even higher centre-of-mass energies