|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Strength evolution and deformation behaviour of cemented paste backfill at early ages: Effect of curing stress, filling strategy and drainage显示文摘In this study, a pressure cell apparatus is developed to investigate the early age evolution of the strength and deformation behaviour of cemented paste backfill(CPB) when subjected to various loading conditions under different curing scenarios. The different curing scenarios that are simulated include:(1)drained and undrained conditions,(2) different filling rates,(3) different filling sequences, and(4) different curing stresses. The findings show that drainage, curing stress, curing time and filling rate influence the mechanical and deformation behaviours of CPB materials. The coupled effects of consolidation, drainage and suction contribute to the strength development of drained CPB subjected to curing stress. On the other hand, particle rearrangement caused by the applied pressure and suction development due to self-desiccation plays a significant role in the strength gain of undrained CPB cured under stress.Furthermore, curing stress induces slightly faster rate of cement hydration, which can contribute to strength acquisition. | Ghirian Alireza Fall Mamadou | 2016 | International Journal of Mining Science and Technology2016，26，5： | 17 |
| 2 | Chemically induced changes in the geotechnical response of cementing paste backfill in shaking table test显示文摘Cemented paste backfill(CPB)is extensively used for underground mine support and/or tailings management.However,CPB behavior under cyclic loadings might be affected by the chemistry of its porewater,which often contains sulphate ions.Till today,no studies have addressed the effect of sulphate on the response of CPB to cyclic loadings by using shaking table technique.This study presents new findings of assessing the effect of the sulphate in the pore water of CPB on its geotechnical response to cyclic loading by using shaking table.CPB mixtures were prepared(with and without sulphate),poured into a flexible laminar shear box,cured to 4 h,and then exposed to cyclic loading using one-dimensional(1D)shaking table.Several parameters(e.g.pore water pressure,settlement,lateral deformation,acceleration,electrical conductivity,effective stress,and liquefaction susceptibility)were monitored or determined before,during,and after shaking.Obtained results indicate that the sulphate-bearing CPB cured to 4 h can be prone to liquefaction under the studied conditions.However,sulphate-free CPB samples are resistant to liquefaction.These results are expected to contribute to a better understanding of the effect of water chemistry on the cyclic behavior of CPB,consequently enhancing the cost-effective design of CPB structures. | Imad Alainachi Mamadou Fall | 2021 | Journal of Rock Mechanics and Geotechnical Engineering2021，13，3： | 4 |
| 3 | A column study of the hydro-mechanical behavior of mature fine tailings under atmospheric drying显示文摘In this paper, the hydro-mechanical behavior and physical properties of mature fine tailings(MFT) under atmospheric drying are investigated through a column study. In the study, evaporation takes place in the development of suction in the upper parts of the column and increasing suction leads to higher strength in the tailings. After 5 days, the suction in the first lift is around 17 k Pa in the upper part of the column.When a second lift is added, the first lift initially loses strength but over a 30 days' period, the strength is recovered to its prior value and suction in the second lift reaches 500 k Pa. The vane shear strength values show a substantial increase in the strength of the MFT after 30 days under atmospheric drying and drainage. The 90% strength found in the column exceeds the threshold(5 k Pa). The hydraulic-mechanical properties of the deposited tailings are closely coupled due to several mechanisms, such as evaporation,drainage, self-consolidation, suction and crack development. The findings of this study will provide a better understanding of the placement behavior of multiple lifts of MFT and thus contribute to reclamation design standards and reduce the use of dedicated disposal areas. | Anis Roshani Mamadou Fall Kevin Kennedy | 2017 | International Journal of Mining Science and Technology2017，27，2： | 2 |
| 4 | Geotechnical characterization of peat-based landfill cover materials显示文摘Natural methane(CH_4) oxidation that is carried out through the use of landfill covers(biocovers) is a promising method for reducing CH_4 emissions from landfills.Previous studies on peat-based landfill covers have mainly focused on their biochemical properties(e.g.CH_4 oxidation capacity).However,the utilization of peat as a cover material also requires a solid understanding of its geotechnical properties(thermal,hydraulic,and mechanical),which are critical to the performance of any biocover.Therefore,the objective of this context is to investigate and assess the geotechnical properties of peat-based cover materials(peat,peat-sand mixture),including compaction,consolidation,and hydraulic and thermal conductivities.The studied materials show high compressibility to the increase of vertical stress,with compression index(C_c) values ranging from 0.16 to 0.358.The compressibility is a function of sand content such that the peat-sand mixture(1:3) has the lowest C_c value.Both the thermal and hydraulic conductivities are functions of moisture content,dry density,and sand content.The hydraulic conductivity varies from 1.74 × 10^(-9) m/s to 7.35 × 10^(-9) m/s,and increases with the increase in sand content.The thermal conductivity of the studied samples varies between 0.54 W/(m K) and 1.41 W/(m K) and it increases with the increases in moisture and sand contents.Increases in sand content generally increase the mechanical behavior of peat-based covers;however,they also cause relatively high hydraulic and thermal conductivities which are not favored properties for biocovers. | Afshin Khoshand Mamadou Fall | 2016 | Journal of Rock Mechanics and Geotechnical Engineering2016，8，5： | 2 |
| 5 | A multiphysics-viscoplastic cap model for simulating blast response of cemented tailings backfill显示文摘Although a large number of previous researches have significantly contributed to the understanding of the quasi-static mechanical behavior of cemented tailings backfill,an evolutive porous medium used in underground mine cavities,very few efforts have been made to improve the knowledge on its response under sudden dynamic loading during the curing process.In fact,there is a great need for such information given that cemented backfill structures are often subjected to blast loadings due to mine exploitations.In this study,a coupled thermo-hydro-mechanical-chemical(THMC)-viscoplastic cap model is developed to describe the behavior of cementing mine backfill material under blast loading.A THMC model for cemented backfill is adopted to evaluate its behavior and evolution of its properties in curing processes with coupled thermal,hydraulic,mechanical and chemical factors.Then,the model is coupled to a Perzyna type of viscoplastic model with a modified smooth surface cap envelope and a variable bulk modulus,in order to reasonably capture the nonlinear and rate-dependent behaviors of the cemented tailings backfill under blast loading.All of the parameters required for the variable-modulus viscoplastic cap model were obtained by applying the THMC model to reproducing evolution of cemented paste backfill(CPB)properties in the curing process.Thus,the behavior of hydrating cemented backfill under high-rate impacts can be evaluated under any curing time of concern.The validation results of the proposed model indicate a good agreement between the experimental and the simulated results.The authors believe that the proposed model will contribute to a better understanding of the performance of hydrating cemented backfill under blasting,and also to practical risk management of backfill structures associated with such a dynamic condition. | Gongda Lu Mamadou Fall Liang Cui | 2017 | Journal of Rock Mechanics and Geotechnical Engineering2017，9，3： | 1 |
| 6 | Swelling ability and behaviour of bentonite-based materials for deep repository engineered barrier systems:Influence of physical,chemical and thermal factors显示文摘Compacted bentonite-sand(B/S)mixtures have been used as a barrier material in engineered barrier systems(EBSs)of deep geological repositories(DGR)to store nuclear wastes.This study investigates the individual and combined effects of different chemical compositions of deep groundwaters(chemical factor)at potential repository sites in Canada(the Trenton and Guelph regions in Ontario),heat generated in DGRs(thermal factor),dry densities and mass ratios of bentonite and sand mixtures(physical factors)on the swelling behavior and ability of bentonite-based materials.In this study,swelling tests are conducted on B/S mixtures with different B/S mix ratios(20/80 to 70/30),compacted at different dry densities(ρd=1.6-2 g/cm^(3)),saturated with different types of water(distilled water and simulated deep groundwater of Trenton and Guelph)and exposed to different temperatures(20℃-80℃).Moreover,scanning electron microscopy(SEM)analyses,mercury intrusion porosimetry(MIP)tests and X-ray diffractometry(XRD)analyses are carried out to evaluate the morphological,microstructural and mineralogical characteristics of the B/S mixtures.The test results indicate that the swelling potential of the B/S mixtures is significantly affected by these physical and chemical factors as well as the combined effects of the chemical and thermal factors.A significant decrease in the swelling capacity is observed when the B/S materials are exposed to the aforementioned groundwaters.A large decrease in the swelling capacity is observed for higher bentonite content in the mixtures.Moreover,higher temperatures intensify the chemically-induced reduction of the swelling capacity of the B/S barrier materials.This decrease in the swelling capacity is caused by the chemical and/or microstructural changes of the materials.The results from this research will help engineers to design and build EBSs for DGRs with similar groundwater and thermal conditions. | Mohammed Alzamel Mamadou Fall Sada Haruna | 2022 | Journal of Rock Mechanics and Geotechnical Engineering2022，14，3： | 1 |
| 7 | Mineralogical Characterisation of the Sedimentary Phosphate Deposit of Tobene (Western Senegal)显示文摘 | Moustapha Diagne Mamadou Fall Mouhamadou Bachir Diouf Ndeye Penda Dione El Hadji MansourSamb | 2016 | Journal of Shipping and Ocean Engineering2016，6，4： | 1 |
| 8 | An evolutive elasto-plastic model for ce- mented paste backfill 显示文摘 | Liang Cui Mamadou Fall | 2016 | Computers and Geotechnics2016，71，： | 1 |
| 9 | Coupled effects of sulphate and temperature on the strength development of cemented tailings backfills: Portland cement-paste backfill显示文摘 | Mamadou Fall Mukesh Pokharel | 2010 | Cement and Concrete Composites2010，，10： | 1 |
| 10 | Coupled modeling of tem- perature distribution and evolution in cemented tailings back- fill structures that contain mineral admixtures显示文摘 | Di Wu Mamadou Fall Si-jing Cai | 2012 | Geotechni- cal and Geological Engineering2012，30，4： | 1 |
| 11 | Experimental characterization of the stress–strain behaviour of cemented paste backfill in compression显示文摘 | Mamadou Fall T. Belem S. Samb M. Benzaazoua | 2007 | Journal of Materials Science2007，，11： | 1 |
您所在的机构暂未开通此部分的功能，请联系管理员