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International Journal of Mining Science and Technology 2015年第3期25卷 439-445页

作者： mohammadi mohammad hossaini mohammad farouq Mirzapour Bahman Hajiantilaki Nabiollah General Mechanic Co. Faculty of Mining Engineering Engineering University CollegeUniversity of Tehran

In order to increase the safety of working environment and decrease the unwanted costs related to overbreak in tunnel excavation projects, it is necessary to minimize overbreak percentage. Thus, based on regression analysis and fuzzy inference system, this paper tries to develop predictive models to estimate overbreak caused by blasting at the Alborz Tunnel. To develop the models, 202 datasets were utilized, out of which 182 were used for constructing the models. To validate and compare the obtained results,determination coefficient(R2) and root mean square error(RMSE) indexes were chosen. For the fuzzy model, R2 and RMSE are equal to 0.96 and 0.55 respectively, whereas for regression model, they are 0.41 and 1.75 respectively, proving that the fuzzy predictor performs, significantly, better than the statistical method. Using the developed fuzzy model, the percentage of overbreak was minimized in the Alborz Tunnel.

关键词： Fuzzy model Overbreak Regression analysis Underground blasting Alborz Tunnel

Modification of rock mass rating system:Interbedding of strong and weak rock layers

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1165-1170页

作者： mohammad mohammadi mohammad farouq hossaini The Alborz Tunnel Site Geodata EngineeringMazandaran ProvinceIran Faculty of Mining Engineering Engineering University CollegeUniversity of TehranTehranIran

Rock mass classification systems are the very important part for underground projects and rock mass rating(RMR) is one of the most commonly applied classification systems in numerous civil and mining projects. The type of rock mass consisting of an interbedding of strong and weak layers poses difficulties and uncertainties for determining the RMR. For this, the present paper uses the concept of rock bolt supporting factor(RSF) for modification of RMR system to be used in such rock mass types. The proposed method also demonstrates the importance of rock bolting practice in such rock masses. The geological parameters of the Shemshak Formation of the Alborz Tunnel in Iran are used as case examples for development of the theoretical approach.

关键词： Rock mass rating(RMR) Strong and weak rock layers Interbedding Rock bolt supporting factor(RSF) Alborz tunnel

Prediction of representative deformation modulus of longwall panel roof rock strata using Mamdani fuzzy system

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International Journal of Mining Science and Technology 2015年第1期25卷 23-30页

作者： mohammad Rezaei Mostafa Asadizadeh Abbas Majdi mohammad farouq hossaini School of Mining Engineering College of Engineering University of Tehran

Deformation modulus is the important parameter in stability analysis of tunnels, dams and mining struc- tures. In this paper, two predictive models including Mamdani fuzzy system （MFS） and multivariable regression analysis （MVRA） were developed to predict deformation modulus based on data obtained from dilatometer tests carried out in Bakhtiary dam site and additional data collected from longwall coal mines. Models inputs were considered to be rock quality designation, overburden height, weathering, unconfined compressive strength, bedding inclination to core axis, joint roughness coefficient and fill thickness. To control the models performance, calculating indices such as root mean square error （RMSE）, variance account for （VAF） and determination coefficient （R^2） were used. The MFS results show the significant prediction accuracy along with high performance compared to MVRA results. Finally, the sensitivity analysis of MFS results shows that the most and the least effective parameters on deformation modulus are weatherin~ and overburden height, respectively.

关键词： Deformation modulusDilatometer testMamdani fuzzy systemMultivariable regression analysis

Development of a time-dependent energy model to calculate the mining-induced stress over gates and pillars

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 306-317页

作者： mohammad Rezaei mohammad farouq hossaini Abbas Majdi School of Mining Engineering College of Engineering University of Tehran

Generally, longwall mining-induced stress results from the stress relaxation due to destressed zone that occurs above the mined panel. Knowledge of induced stress is very important for accurate design of adjacent gateroads and intervening pillars which helps to raise the safety and productivity of longwall mining operations. This study presents a novel time-dependent analytical model for determination of the longwall mining-induced stress and investigates the coefficient of stress concentration over adjacent gates and pillars. The model is developed based on the strain energy balance in longwall mining incorporated to a rheological constitutive model of caved materials with time-varying parameters. The study site is the Tabas coal mine of Iran. In the proposed model, height of destressed zone above the mined panel, total longwall mining-induced stress, abutment angle, induced vertical stress, and coefficient of stress concentration over neighboring gates and intervening pillars are calculated. To evaluate the effect of proposed model parameters on the coefficient of stress concentration due to longwall mining, sensitivity analysis is performed based on the field data and experimental constants. Also, the results of the proposed model are compared with those of existing models. The comparative results confirm a good agreement between the proposed model and the in situ measurements. According to the obtained results, it is concluded that the proposed model can be successfully used to calculate the longwall mining-induced stress. Therefore, the optimum design of gate supports and pillar dimensions would be attainable which helps to increase the mining efficiency.

关键词： Longwall mining Strain energy Time-dependent model Destressed zone Mining-induced stress