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A Closer Look at the Design of Cutterheads for Hard Rock Tunnel-Boring Machines

Engineering 2017年第6期3卷 892-904页

作者： jamal rostami Soo-Ho Chang Excavation Engineering and Earth Mechanics Institute Department of Mining Engineering Colorado School of Mines Golden CO 80401 USA Geotechnical Engineering Research Institute Korea Institute of Civil Engineering and Building Technology Goyang 10223 Korea

The success of a tunnel-boring machine （TBM） in a given project depends on the functionality of all components of the system, from the cutters to the backup system, and on the entire rolling stock. However, no part of the machine plays a more crucial role in the efficient operation of the machine than its cutterhead. The design of the cutterhead impacts the efficiency of cutting, the balance of the head, the life of the cutters, the maintenance of the main bearing/gearbox, and the effectiveness of the mucking along with its effects on the wear of the face and gage cutters/muck buckets. Overall, cutterhead design heavily impacts the rate of penetration （ROP）, rate of machine utilization （U）, and daffy advance rate （AR）. Although there has been some discussion in commonly available publications regarding disk cutters, cutting forces, and some design features of the head, there is limited literature on this subject because the design of cutter- heads is mainly handled by machine manufacturers. Most of the design process involves proprietary algorithms by the manufacturers, and despite recent attention on the subject, the design of rock TBMs has been somewhat of a mystery to most end-users. This paper is an attempt to demystify the basic concepts in design. Although it may not be sufficient for a full-fledged design by the readers, this paper allows engineers and contractors to understand the thought process in the design steps, what to Look for in a proper design, and the implications of the head design on machine operation and life cycle.

关键词： TBM cutterhead design Cutterhead layout Disk cutters Cutting pattern TBM efficiency

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Application of new void detection algorithm for analysis of feed pressure and rotation pressure of roof bolters

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International Journal of Mining Science and Technology 2017年第1期27卷 77-81页

作者： Liu Wenpeng jamal rostami Eric Keller Department of Energy and Mineral Engineering The Pennsylvania State UniversityState CollegePA 16802USA Earth Mechanics Institute Department of Mining EngineeringColorado School of MineGoldenCO 80401USA Electro-Mechanical Systems Laboratory The Pennsylvania State UniversityState CollegePA 16802USA

Roof and rib instability is an important issue in underground mining. To optimize ground support design,enhance ground stability, and reduce the possibility of roof or rib failure with minimal use of artificial ground support, it is essential to have an accurate understanding of ground conditions. This includes the location of voids, cracks, and discontinuities, as well as information about the different strata in the immediate roof. This paper briefly introduces ongoing research on void detection by using the roof bolter feed and rotation pressure. The goal of this project is to improve the sensitivity of detection programs to locate smaller joints and reduce the number of false alarms. This paper presents a brief review of the testing procedures, data analysis, logic, and algorithms used for void detection. In addition, this paper discusses the results of preliminary laboratory tests and statistical analysis of the data from these two drilling parameters used for void detection.

关键词： Roof bolter Void detection Feed pressure Rotation pressure CUSUM algorithm Ground support optimization

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Examining the effect of adverse geological conditions on jamming of a single shielded TBM in Uluabat tunnel using numerical modeling

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1112-1122页

作者： Rohola Hasanpour Jürgen Schmitt Yilmaz Ozcelik jamal rostami Institute for Tunneling and Construction Management Ruhr-University Bochum Department of Civil Engineering Darmstadt University of Applied Science Department of Mining Engineering Hacettepe University Department of Mining Engineering Colorado School of Mines

Severe shield jamming events have been reported during excavation of Uluabat tunnel through adverse geological conditions, which resulted in several stoppages at advancing a single shielded tunnel boring machine(TBM). To study the jamming mechanism, three-dimensional(3D) simulation of the machine and surrounding ground was implemented using the finite difference code FLAC3D. Numerical analyses were performed for three sections along the tunnel with a higher risk for entrapment due to the combination of overburden and geological conditions. The computational results including longitudinal displacement contours and ground pressure profiles around the shield allow a better understanding of ground behavior within the excavation. Furthermore, they allow realistically assessing the impact of adverse geological conditions on shield jamming. The calculated thrust forces, which are required to move the machine forward, are in good agreement with field observations and measurements. It also proves that the numerical analysis can effectively be used for evaluating the effect of adverse geological environment on TBM entrapments and can be applied to prediction of loads on the shield and preestimating of the required thrust force during excavation through adverse ground conditions.

关键词： Single shielded tunnel boring machine(TBM) Numerical modeling Shield jamming Squeezing ground Uluabat tunnel

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Prediction of TBM jamming risk in squeezing grounds using Bayesian and artificial neural networks

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第1期12卷 21-31页

作者： Rohola Hasanpour jamal rostami Jürgen Schmitt Yilmaz Ozcelik Babak Sohrabian Institute for Tunneling and Construction Management Ruhr-University BochumBochumGermany Department of Mining Engineering Colorado School of MinesGoldenUSA Department of Civil Engineering Darmstadt University of Applied ScienceDarmstadtGermany Department of Mining Engineering Hacettepe UniversityAnkaraTurkey Faculty of Mining and Metallurgical Engineering Urmia University of TechnologyUrmiaIran

This study presents an application of artificial neural network(ANN)and Bayesian network(BN)for evaluation of jamming risk of the shielded tunnel boring machines(TBMs)in adverse ground conditions such as squeezing *** analysis is based on database of tunneling cases by numerical modeling to evaluate the ground convergence and possibility of machine *** results of initial numerical analysis were verified in comparison with some case studies.A dataset was established by performing additional numerical modeling of various scenarios based on variation of the most critical parameters affecting shield *** includes compressive strength and deformation modulus of rock mass,tunnel radius,shield length,shield thickness,in situ stresses,depth of over-excavation,and skin friction between shield and *** the dataset,an ANN was trained to predict the contact pressures from a series of ground properties and machine ***,the continuous and discretized BNs were used to analyze the risk of shield *** results of these two different BN methods are compared to the field observations and summarized in this *** developed risk models can estimate the required thrust force in both *** BN models can also be used in the cases with incomplete geological and geomechanical properties.

关键词： Bayesian network(BN) Artificial neural network(ANN) Shielded tunnel boring machine(TBM) Jamming risk Numerical simulation Squeezing ground

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Ground characterization and roof mapping: Online sensor signal-based change detection

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International Journal of Mining Science and Technology 2015年第6期25卷 905-913页

作者： Bahrampour Soheil rostami jamal Ray Asok Naeimipour Ali Collins Craig Electrical Engineering Department The Pennsylvania State University Department of Energy and Mineral Engineering The Pennsylvania State University J. H. Fletcher & Co.TM

Measurement while drilling systems are becoming an important part of excavation operations for rock characterization and ground support design that require reliable information on rock strength and location ＆ frequency of joints or voids. This paper focuses on improving rock characterization algorithms for instrumented roof-boRer systems. For this purpose, an improved void detection algorithm is proposed, where the underlying theory is built upon the concept of mean change detection based on the feed pressure signals. In addition, the application of acoustic sensing for void detection is examined and it is shown that the variance of the filtered acoustic signal is correlated to the strength of the material being drilled. The proposed algorithm has been validated on the data collected from full-scale drilling tests in various concrete and rock samples at the J. H. Fletcher facility.

关键词： Measurement while drilling systemsRoof mappingVoid detectionOnline change detection

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Rock characterization while drilling and application of roof bolter drilling data for evaluation of ground conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 273-281页

作者： jamal rostami Sair Kahraman Ali Naeimipour Craig Collins Department of Energy and Mineral Engineering Pennsylvania State University Mining Engineering Department Hacettepe University J.H. Fletcher & Co.

Despite recent advances in mine health and safety, roof collapse and instabilities are still the leading causes of injury and fatality in underground mining operations. Improving safety and optimum design of ground support requires good and reliable ground characterization. While many geophysical methods have been developed for ground characterizations, their accuracy is insufficient for customized ground support design of underground workings. The actual measurements on the samples of the roof and wall strata from the exploration boring are reliable but the related holes are far apart, thus unsuitable for design purposes. The best source of information could be the geological back mapping of the roof and walls, but this is disruptive to mining operations, and provided information is only from rock *** of the data obtained from roof bolt drilling can offer a good and reliable source of information that can be used for ground characterization and ground support design and evaluations. This paper offers a brief review of the mine roof characterization methods, followed by introduction and discussion of the roof characterization methods by instrumented roof bolters. A brief overview of the results of the preliminary study and initial testing on an instrumented drill and summary of the suggested improvements are also discussed.

关键词： Roof bolter Rock characterization Three-dimensional(3D) visualization of ground Ground support optimization

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Prediction of flyrock distance induced by mine blasting using a novel Harris Hawks optimization-based multi-layer perceptron neural network

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第6期13卷 1413-1427页

作者： Bhatawdekar Ramesh Murlidhar Hoang Nguyen jamal rostami XuanNam Bui Danial Jahed Armaghani Prashanth Ragam Edy Tonnizam Mohamad Centre of Tropical Geoengineering(Geotropik) School of Civil EngineeringFaculty of EngineeringUniversiti Teknologi MalaysiaSkudaiJohor81310Malaysia Department of Mining Engineering Indian Institute of TechnologyKharagpur721302India Department of Surface Mining Mining FacultyHanoi University of Mining and GeologyHanoi100000Viet Nam Innovations for Sustainable and Responsible Mining(ISRM)Group Hanoi University of Mining and GeologyHanoi100000Viet Nam Department of Mining Engineering Earth Mechanics InstituteColorado School of MinesGoldenCO80401USA Department of Urban Planning Engineering Networks and SystemsInstitute of Architecture and ConstructionSouth Ural State UniversityChelyabinsk454080Russia Department of ECE Kakatiya Institute of Technology and ScienceWarangal506015India

In mining or construction projects,for exploitation of hard rock with high strength properties,blasting is frequently applied to breaking or moving them using high explosive ***,use of explosives may lead to the flyrock *** can damage structures or nearby equipment in the surrounding areas and inflict harm to humans,especially workers in the working ***,prediction of flyrock is of high *** this investigation,examination and estimation/forecast of flyrock distance induced by blasting through the application of five artificial intelligent algorithms were carried *** hundred and fifty-two blasting events in three open-pit granite mines in Johor,Malaysia,were monitored to collect field *** collected data include blasting parameters and rock mass ***-specific weathering index(WI),geological strength index(GSI) and rock quality designation(RQD)are rock mass ***-layer perceptron(MLP),random forest(RF),support vector machine(SVM),and hybrid models including Harris Hawks optimization-based MLP(known as HHO-MLP) and whale optimization algorithm-based MLP(known as WOA-MLP) were *** performance of various models was assessed through various performance indices,including a10-index,coefficient of determination(R^(2)),root mean squared error(RMSE),mean absolute percentage error(MAPE),variance accounted for(VAF),and root squared error(RSE).The a10-index values for MLP,RF,SVM,HHO-MLP and WOA-MLP are 0.953,0.933,0.937,0.991 and 0.972,respectively.R^(2) of HHO-MLP is 0.998,which achieved the best performance among all five machine learning(ML) models.

关键词： Flyrock Harris hawks optimization(HHO) Multi-layer perceptron(MLP) Random forest(RF) Support vector machine(SVM) Whale optimization algorithm(WOA)

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复杂开采条件下深部硬岩板裂化破坏试验与模拟研究进展和关键问题

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中国矿业大学学报 2023年第5期52卷 868-888页

作者：陈绍杰冯帆李夕兵王成李地元 rostami jamal 朱泉企山东科技大学能源与矿业工程学院山东青岛266590 山东黄金矿业(莱州)有限公司焦家金矿湖南长沙410083 中南大学资源与安全工程学院矿山东莱州261441 科罗拉多矿业大学地球力学研究所美国戈尔登80401

板裂化破坏是深部硬岩巷道或硐室典型的破坏形式,严重制约了深部矿产资源的安全高效开发与利用.板裂化破坏诱发因素、发生机制以及控制对策研究已成为岩石力学领域的前沿和热点问题.本文以深部硬岩所处的复杂赋存环境与开采条件为出发点... 详细信息

板裂化破坏是深部硬岩巷道或硐室典型的破坏形式,严重制约了深部矿产资源的安全高效开发与利用.板裂化破坏诱发因素、发生机制以及控制对策研究已成为岩石力学领域的前沿和热点问题.本文以深部硬岩所处的复杂赋存环境与开采条件为出发点,从开采因素(工程结构尺寸和开挖速率)、环境因素(地质构造和应力环境)和锚固控制3个方面,系统梳理和总结了板裂化破坏在室内试验以及数值模拟方面的研究现状与发展历程.在此基础上,凝练了目前深部硬岩板裂化破坏试验模拟研究中存在的关键科学问题以及关键技术难题.为了保障深井矿山安全高效开采,亟需对深部复杂开采条件下硬岩板裂化破坏机制以及灾害防控开展更为深入和系统的研究,以期为深地矿产资源可持续开发利用提供理论与技术支撑.

关键词：岩石力学深部开采板裂复杂开采条件破坏行为控制机制科学问题技术难题

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基于测井技术的矿井围岩强度预测与分级技术研究进展

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地球物理学进展 2014年第3期29卷 1452-1457页

作者：于宪阳徐华君 jamal rostami 李宝玉中国矿业大学矿业工程学院、深部煤炭资源开采国家重点实验室徐州221116 Pennsylvania State University State CollegePA 16803US

矿井围岩赋存条件是煤矿生产的先决条件,它可以影响到矿井生产的各个阶段.传统的矿井围岩强度测试与分级方法需要进行大量的实验室岩石强度测试测试工作,耗费时间且效率较低,并且在围岩破碎区域常常无法取得合格的强度测试试件.而基于... 详细信息

矿井围岩赋存条件是煤矿生产的先决条件,它可以影响到矿井生产的各个阶段.传统的矿井围岩强度测试与分级方法需要进行大量的实验室岩石强度测试测试工作,耗费时间且效率较低,并且在围岩破碎区域常常无法取得合格的强度测试试件.而基于地球物理测井技术的采矿围岩强度预测与分类技术具有快速、经济、高效的特点,近年来已成为美、澳等采矿强国的研究热点之一.当前这一技术的主要研究手段包括声波测井法、地球物理围岩分级方法、自然伽马能谱结合瞬时中子伽马活度方法、钻孔窥视方法等.本文介绍了世界上这一领域的最新研究进展,讨论了它的发展趋势,阐明了我国在这一领域中需要跟进的研究方向.

关键词：地球物理测井围岩强度围岩分级采矿工程

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A comparative in vitro study on the effect of SGLT2 inhibitors on chemosensitivity to doxorubicin in MCF-7 breast cancer cells

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Oncology Research 2024年第5期32卷 817-830页

作者： SHAHID KARIM ALANOUD NAHER ALGHANMI MAHA jamal HUDA ALKREATHY ALAM jamal HIND A.ALKHATABI MOHAMMED BAZUHAIR AFTAB AHMAD Department of Clinical Pharmacology Faculty of MedicineKing Abdulaziz UniversityJeddahSaudi Arabia Department of Biochemistry Faculty of ScienceKing Abdulaziz UniversityJeddahSaudi Arabia Department of Biochemistry College of ScienceUniversity of JeddahJeddah21959Saudi Arabia Health Information Technology Department The Applied CollegeKing Abdulaziz UniversityJeddahSaudi Arabia Pharmacovigilance and Medication Safety Unit Center of Research Excellence for Drug Research and Pharmaceutical IndustriesKing Abdulaziz UniversityJeddahSaudi Arabia

Cancer frequently develops resistance to the majority of chemotherapy *** study aimed to examine the synergistic cytotoxic and antitumor effects of SGLT2 inhibitors,specifically Canagliflozin(CAN),Dapagliflozin(DAP),Empagliflozin(EMP),and Doxorubicin(DOX),using in vitro *** precise combination of CAN+DOX has been found to greatly enhance the cytotoxic effects of doxorubicin(DOX)in MCF-7 ***,it was shown that cancer cells exhibit an increased demand for glucose and ATP in order to support their ***,when these medications were combined with DOX,there was a considerable inhibition of glucose consumption,as well as reductions in intracellular ATP and lactate ***,this effect was found to be dependent on the dosages of the *** addition to effectively inhibiting the cell cycle,the combination of CAN+DOX induces substantial modifications in both cell cycle and apoptotic gene *** work represents the initial report on the beneficial impact of SGLT2 inhibitor medications,namely CAN,DAP,and EMP,on the responsiveness to the anticancer properties of *** underlying molecular mechanisms potentially involve the suppression of the function of SGLT2.

关键词： SGLT2 Cancer Cytotoxicity ATP Cell cycle

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