The objective of this study is to investigate the effect of temperature on the physical and mechanical properties of standard mortar reinforced with steel fibers, polypropylene fibers and hybrid fibers. Non-destructive tests (capillary water absorption, interconnected porosity, gas permeability, ultrasound celerity) were carried out on samples that had been heated, at a temperature ramp of 5 °C/min, to maximum temperature of: 105 °C, 400 °C, 500 °C et 800 °C. The results show a good correlation between the evolution of properties and the damage resulting from the imposed heat exposure treatment. The study shows that there is a significant deterioration of physico-mechanical properties of the fiber mortars above 500 °C. The hybrid fiber mortars show a good compromise: the polypropylene fibers guarantee a thermal stability whereas the steel fibers act to conserve good mechanical behavior.
{"title":"Non-destructive characterisation of mortars reinforced with various fibres exposed to high temperature","authors":"M. Ezziane, Laurent Molez, I. Messaoudene","doi":"10.5277/MSC182513","DOIUrl":"https://doi.org/10.5277/MSC182513","url":null,"abstract":"The objective of this study is to investigate the effect of temperature on the physical and mechanical properties of standard mortar reinforced with steel fibers, polypropylene fibers and hybrid fibers. Non-destructive tests (capillary water absorption, interconnected porosity, gas permeability, ultrasound celerity) were carried out on samples that had been heated, at a temperature ramp of 5 °C/min, to maximum temperature of: 105 °C, 400 °C, 500 °C et 800 °C. The results show a good correlation between the evolution of properties and the damage resulting from the imposed heat exposure treatment. The study shows that there is a significant deterioration of physico-mechanical properties of the fiber mortars above 500 °C. The hybrid fiber mortars show a good compromise: the polypropylene fibers guarantee a thermal stability whereas the steel fibers act to conserve good mechanical behavior.","PeriodicalId":43629,"journal":{"name":"Mining Science","volume":"24 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80775506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qiao Shuo, A. Wang, Xia Yimin, Z. Liu, J. S. Liu, M. Yang
{"title":"Influence of pick layouts on the performance of bolter miner cutting head","authors":"Qiao Shuo, A. Wang, Xia Yimin, Z. Liu, J. S. Liu, M. Yang","doi":"10.5277/MSC182511","DOIUrl":"https://doi.org/10.5277/MSC182511","url":null,"abstract":"","PeriodicalId":43629,"journal":{"name":"Mining Science","volume":"14 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74798671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents the results of investigations into stress distribution in the adhesive bonds of multiply conveyor belt splices. The splices were cold-vulcanized with the use of chemically hardening glues having various strength parameters. The research results demonstrated that the length of splices may be reduced without the risk of lowering their tensile strength and fatigue life. The paper presents stress values in adhesive joints of various belt types and the influence that the properties of belts, splices and splicing materials have on stress values in the adhesive bond of the splice.
{"title":"Optimizing splice geometry in multiply conveyor belts with respect to stress in adhesive bonds","authors":"M. Bajda, R. Blazej, M. Hardygóra","doi":"10.5277/MSC182514","DOIUrl":"https://doi.org/10.5277/MSC182514","url":null,"abstract":"This paper presents the results of investigations into stress distribution in the adhesive bonds of multiply conveyor belt splices. The splices were cold-vulcanized with the use of chemically hardening glues having various strength parameters. The research results demonstrated that the length of splices may be reduced without the risk of lowering their tensile strength and fatigue life. The paper presents stress values in adhesive joints of various belt types and the influence that the properties of belts, splices and splicing materials have on stress values in the adhesive bond of the splice.","PeriodicalId":43629,"journal":{"name":"Mining Science","volume":"95 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78745092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Application of hydrochemistry for inrush water source identification in coal mine: approach based on statistical analysis","authors":"L. Sun","doi":"10.5277/MSC182508","DOIUrl":"https://doi.org/10.5277/MSC182508","url":null,"abstract":"","PeriodicalId":43629,"journal":{"name":"Mining Science","volume":"30 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88569616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Experimental Investigation on the Effect of Marble powder on the performance of Selt-Compacting Concrete (SCC)","authors":"L. Belagraa, Nora Said Djebri, Z. Rahmouni","doi":"10.5277/MSC172411","DOIUrl":"https://doi.org/10.5277/MSC172411","url":null,"abstract":"","PeriodicalId":43629,"journal":{"name":"Mining Science","volume":"5 1","pages":"183-194"},"PeriodicalIF":1.3,"publicationDate":"2017-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73937849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
: This study examines the effect of the additions of silica fume and super plasticizer on the mechanical performance of high performance concretes at high temperatures. The tested concretes are formulated with 5% silica fume and two dosages of super plasticizers in the ratio of (2%, 2.5%) the weight of cement after having been exposed to four maximum temperatures, 200 °C, 400 °C, 600 °C and 900 °C without any imposed load during the heating. The results obtained show that the mechanical resistance at 28 day increases with the degree of temperature compared to that measured at 20 °C. On the contrary, a clear decrease is observed between 600 °C and 900 °C. However, material composition seems to have great influence on the mechanical strength.
{"title":"Combined effect of silica fume and additive on the behavior of high performance concretes subjected to high temperatures","authors":"N. Tebbal, Z. Rahmouni, M. Maza","doi":"10.5277/MSC172408","DOIUrl":"https://doi.org/10.5277/MSC172408","url":null,"abstract":": This study examines the effect of the additions of silica fume and super plasticizer on the mechanical performance of high performance concretes at high temperatures. The tested concretes are formulated with 5% silica fume and two dosages of super plasticizers in the ratio of (2%, 2.5%) the weight of cement after having been exposed to four maximum temperatures, 200 °C, 400 °C, 600 °C and 900 °C without any imposed load during the heating. The results obtained show that the mechanical resistance at 28 day increases with the degree of temperature compared to that measured at 20 °C. On the contrary, a clear decrease is observed between 600 °C and 900 °C. However, material composition seems to have great influence on the mechanical strength.","PeriodicalId":43629,"journal":{"name":"Mining Science","volume":"9 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2017-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91289226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Sedira, João Castro-Gomes, G. Kastiukas, Xiangming Zhou, A. Vargas
European Commission under Horizon 2020, Marie Sklodowska-Curie Actions, Research and Innovation Staff Exchange (RISE), by REMINE – “Reuse of Mining Waste into Innovative Geopolymeric-based Structural Panels, Precast, Ready Mixes and Insitu Applications”, Portuguese national funds through FCT - Foundation for Science and Technology, IP, within the research unit C-MADE, Centre of Materials and Building Technologies (CIVE-Central covilha-4082), University of Beira Interior, Portugal.
{"title":"A review on mineral waste for chemical-activated binders: mineralogical and chemical characteristics","authors":"N. Sedira, João Castro-Gomes, G. Kastiukas, Xiangming Zhou, A. Vargas","doi":"10.5277/MSC172402","DOIUrl":"https://doi.org/10.5277/MSC172402","url":null,"abstract":"European Commission under Horizon 2020, Marie Sklodowska-Curie Actions, Research and Innovation Staff Exchange (RISE), by REMINE – “Reuse of Mining Waste into Innovative Geopolymeric-based Structural Panels, Precast, Ready Mixes and Insitu Applications”, Portuguese national funds through FCT - Foundation for Science and Technology, IP, within the research unit C-MADE, Centre of Materials and Building Technologies (CIVE-Central covilha-4082), University of Beira Interior, Portugal.","PeriodicalId":43629,"journal":{"name":"Mining Science","volume":"54 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73172538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
: The current paper presents the study of applying the FEMA method to the drill T4 BH. The research focused on the risk indicators used in the FEMA method. Pareto diagram for the description of the frequency and importance of causes that may cause a problem were applied. With participative method of brainstorming information was gathered concerning the failures that can occur in the drill machine T4BH, their causes and their effects, as well as preventive and error detection methods. The information was then processed by means of different quality instrument (cause-effect diagram) resulting in a ranking of risk coefficient used in the FMEA method.
{"title":"Contribution to the maintenance of T4 BH drilling machine (Case of the mine of Boukhadra, Algeria)","authors":"A. Zoubir, N. Yamina, A. Noura","doi":"10.5277/MSC172404","DOIUrl":"https://doi.org/10.5277/MSC172404","url":null,"abstract":": The current paper presents the study of applying the FEMA method to the drill T4 BH. The research focused on the risk indicators used in the FEMA method. Pareto diagram for the description of the frequency and importance of causes that may cause a problem were applied. With participative method of brainstorming information was gathered concerning the failures that can occur in the drill machine T4BH, their causes and their effects, as well as preventive and error detection methods. The information was then processed by means of different quality instrument (cause-effect diagram) resulting in a ranking of risk coefficient used in the FMEA method.","PeriodicalId":43629,"journal":{"name":"Mining Science","volume":"10 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85296836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Imed Beghoura, João Castro-Gomes, H. Ihsan, N. Estrada
Different combinations of mining waste mud, grounded waste glass, Portland cement, metakaolin and expanded cork were mixed together with alkaline activators (sodium silicate and sodium hydroxide solution) and as well aluminum powder or hydrogen peroxide to produce foamed lightweight materials. The size of the mineral materials is under 500 μm and expanded cork particles size is between 2 to 4 mm. The expanded cork added to the mixes changed between 10 to 40% volume of total solids. The influence of expanded cork on compressive strength was investigated. Precursors and activators were mixed together to produce a homogeneous mixture, which was placed into a cubic mold (40 x 40 x 40 mm), and cured at a temperature of 60°C, for 24 hours. After curing process, samples without foaming agents achieved the maximum compressive strength of 14.7 and 19.5 MPa for 7 and 28 days respectively. The porosity was observed by the naked eye of large voids in range of 4 mm in size. Microstructure analyses were carried on by SEM. Samples made with aluminum powder showed higher volume increase about 358% compared with samples made with hydrogen peroxide that presented a 141% volume increase. This preliminary study shows the feasibility to produce new improved lightweight foamed alkali activated materials incorporating expanded cork with potential applications in artistic, architectural, and historical heritage restoration.
将矿用废泥、磨碎的废玻璃、硅酸盐水泥、偏高岭土和膨胀软木与碱性活化剂(水玻璃和氢氧化钠溶液)以及铝粉或过氧化氢混合，制成泡沫轻质材料。矿物材料粒径在500 μm以下，膨胀软木颗粒粒径在2 ~ 4mm之间。在混合物中加入膨胀软木后，总固体体积的变化幅度在10%到40%之间。研究了膨胀软木对其抗压强度的影响。将前驱体和活化剂混合在一起，形成均匀的混合物，将其放入立方体模具(40 x 40 x 40 mm)中，在60°C的温度下固化24小时。未添加发泡剂的试样在养护后7天和28天的最大抗压强度分别为14.7和19.5 MPa。裸眼观察到孔隙率为4mm左右的大孔洞。用SEM对其进行了微观结构分析。用铝粉制成的样品比用过氧化氢制成的样品体积增加了141%，体积增加了358%。这项初步研究表明，生产新型轻质泡沫碱活化材料的可行性，包括膨胀软木，在艺术、建筑和历史遗产修复方面具有潜在的应用前景。
{"title":"Feasibility of alkali-activated mining waste foamed materials incorporating expanded granulated cork","authors":"Imed Beghoura, João Castro-Gomes, H. Ihsan, N. Estrada","doi":"10.5277/MSC172401","DOIUrl":"https://doi.org/10.5277/MSC172401","url":null,"abstract":"Different combinations of mining waste mud, grounded waste glass, Portland cement, metakaolin and expanded cork were mixed together with alkaline activators (sodium silicate and sodium hydroxide solution) and as well aluminum powder or hydrogen peroxide to produce foamed lightweight materials. The size of the mineral materials is under 500 μm and expanded cork particles size is between 2 to 4 mm. The expanded cork added to the mixes changed between 10 to 40% volume of total solids. The influence of expanded cork on compressive strength was investigated. Precursors and activators were mixed together to produce a homogeneous mixture, which was placed into a cubic mold (40 x 40 x 40 mm), and cured at a temperature of 60°C, for 24 hours. After curing process, samples without foaming agents achieved the maximum compressive strength of 14.7 and 19.5 MPa for 7 and 28 days respectively. The porosity was observed by the naked eye of large voids in range of 4 mm in size. Microstructure analyses were carried on by SEM. Samples made with aluminum powder showed higher volume increase about 358% compared with samples made with hydrogen peroxide that presented a 141% volume increase. This preliminary study shows the feasibility to produce new improved lightweight foamed alkali activated materials incorporating expanded cork with potential applications in artistic, architectural, and historical heritage restoration.","PeriodicalId":43629,"journal":{"name":"Mining Science","volume":"98 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72991868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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