Geological and hydrological characteristics, joint geometric features, rock physical and mechanical properties and rock mass quality are studied in the Beishan area, preselected for China5 s high-level radioactive was...Geological and hydrological characteristics, joint geometric features, rock physical and mechanical properties and rock mass quality are studied in the Beishan area, preselected for China5 s high-level radioactive waste(HLW) disposal engineering. A comprehensive survey method is developed to study joint geometric features in the outcrop and samples from borehole BS06 into the Xinchang rock mass were tested. The optimal joint sets are determined by rose diagrams and equal-area lower hemisphere plots of joint poles. Results show that: 1) the distribution of joint occurrence obeys a normal distribution, while the distribution of joint spacing obeys a negative exponential distribution; 2) concentric circular and tangent circular sampling windows are applied to study the trace length and the trace midpoint density. Results indicate that tangent circular sampling window is more stable and reasonable; 3) Beishan granite shows high density, low porosity and high strength based on many laboratory tests and the physical properties and mechanical properties are closely related; and4) a synthesis index, Joint Structure Rating(JSR), is applied to evaluate the quality of rock mass. Through the research results of rock mass characteristics, the Xinchang rock mass in the Beishan preselected area has the favorable conditions for China's HLW disposal repository site.展开更多
Water scarcity is a serious problem throughout the world for both urban & rural community. Urban centers in India are facing an ironical situation of water scarcity today. This paper includes an Analytical solutio...Water scarcity is a serious problem throughout the world for both urban & rural community. Urban centers in India are facing an ironical situation of water scarcity today. This paper includes an Analytical solution, Numerical modeling, Empirical approaches, In-situ test results to predict recharge (rate) mound of the ground-water and capacity of recharge well which is essential for the proper management of suitable artificial ground-water recharge systems to maintain water balance and stop salt water intrusion. Authors have derived analytical equation for predicting growth as well as decline of the ground-water mound depending on the intensity of recharge rate qr with different value of permeability k, depth of pervious strata H and diameter of well d, also studying the effects of variation in the geotechnical parameters on water-table fluctuations. In this paper to study the impact of numerical modeling using quadratic equation for unconfined aquifer base on rainfall intensity P and a change in saturated thickness H with variation in piezometric level. Empirical approaches are for evaluation of correct value of k of an undercharged unconfined aquifer with drawdown s0, influence zone L, recharge rate qr. In-situ test results give actual correlation between value of recharging rate of well and permeability on field. Authors have verified recharging rate of installed well from all approaches. A result obtained from the various field case studies gives the validation of the derived equation. Scientific quality measures of aquifer water are also recorded.展开更多
Soil particle size distribution(PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives o...Soil particle size distribution(PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives of this work were: 1) to partition PSD of 75 soil samples, collected from a flat field in the University of Guilan, Iran, into two scaling domains using a piecewise fractal model to evaluate the relationships between fractal dimensions of scaling domains and soil clay, silt, and sand fractions and 2) to assess the potential of fractal parameters as an index used in a geostatistical approach reflecting the spatial variability of soil texture. Features of PSD of soil samples were studied using fractal geometry, and geostatistical techniques were used to characterize the spatial variability of fractal and soil textural parameters. There were two scaling domains for the PSD of soil samples. The fractal dimensions of these two scaling domains(D_1 and D_2) were then used to characterize different ranges of soil particle sizes and their relationships to the soil textural parameters. There was a positive correlation between D_1 and clay content(R^2= 0.924), a negative correlation between D_1 and silt content(R^2= 0.801), and a negative correlation between D_2 and sand content(R^2= 0.913). The geometric mean diameter of soil particles had a negative correlation with D_1(R^2= 0.569) and D_2(R^2= 0.682). Semivariograms of fractal dimensions and soil textural parameters were calculated and the maps of spatial variation of D_1 and D_2 and soil PSD parameters were provided using ordinary kriging. The results showed that there were also spatial correlations between D_1 and D_2 and particle size fractions.According to the semivariogram models and validation parameters, the fractal parameters had powerful spatial structure and could better describe the spatial variability of soil texture.展开更多
基金supported by the High-level Talent Research Launch Project, Chongqing Technology and Business University, under grant No. 950318066the Open Research Fund of the State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, under grant No. Z017010the National Natural Science Foundation of China, under grant No. 41688103
文摘Geological and hydrological characteristics, joint geometric features, rock physical and mechanical properties and rock mass quality are studied in the Beishan area, preselected for China5 s high-level radioactive waste(HLW) disposal engineering. A comprehensive survey method is developed to study joint geometric features in the outcrop and samples from borehole BS06 into the Xinchang rock mass were tested. The optimal joint sets are determined by rose diagrams and equal-area lower hemisphere plots of joint poles. Results show that: 1) the distribution of joint occurrence obeys a normal distribution, while the distribution of joint spacing obeys a negative exponential distribution; 2) concentric circular and tangent circular sampling windows are applied to study the trace length and the trace midpoint density. Results indicate that tangent circular sampling window is more stable and reasonable; 3) Beishan granite shows high density, low porosity and high strength based on many laboratory tests and the physical properties and mechanical properties are closely related; and4) a synthesis index, Joint Structure Rating(JSR), is applied to evaluate the quality of rock mass. Through the research results of rock mass characteristics, the Xinchang rock mass in the Beishan preselected area has the favorable conditions for China's HLW disposal repository site.
文摘Water scarcity is a serious problem throughout the world for both urban & rural community. Urban centers in India are facing an ironical situation of water scarcity today. This paper includes an Analytical solution, Numerical modeling, Empirical approaches, In-situ test results to predict recharge (rate) mound of the ground-water and capacity of recharge well which is essential for the proper management of suitable artificial ground-water recharge systems to maintain water balance and stop salt water intrusion. Authors have derived analytical equation for predicting growth as well as decline of the ground-water mound depending on the intensity of recharge rate qr with different value of permeability k, depth of pervious strata H and diameter of well d, also studying the effects of variation in the geotechnical parameters on water-table fluctuations. In this paper to study the impact of numerical modeling using quadratic equation for unconfined aquifer base on rainfall intensity P and a change in saturated thickness H with variation in piezometric level. Empirical approaches are for evaluation of correct value of k of an undercharged unconfined aquifer with drawdown s0, influence zone L, recharge rate qr. In-situ test results give actual correlation between value of recharging rate of well and permeability on field. Authors have verified recharging rate of installed well from all approaches. A result obtained from the various field case studies gives the validation of the derived equation. Scientific quality measures of aquifer water are also recorded.
文摘Soil particle size distribution(PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives of this work were: 1) to partition PSD of 75 soil samples, collected from a flat field in the University of Guilan, Iran, into two scaling domains using a piecewise fractal model to evaluate the relationships between fractal dimensions of scaling domains and soil clay, silt, and sand fractions and 2) to assess the potential of fractal parameters as an index used in a geostatistical approach reflecting the spatial variability of soil texture. Features of PSD of soil samples were studied using fractal geometry, and geostatistical techniques were used to characterize the spatial variability of fractal and soil textural parameters. There were two scaling domains for the PSD of soil samples. The fractal dimensions of these two scaling domains(D_1 and D_2) were then used to characterize different ranges of soil particle sizes and their relationships to the soil textural parameters. There was a positive correlation between D_1 and clay content(R^2= 0.924), a negative correlation between D_1 and silt content(R^2= 0.801), and a negative correlation between D_2 and sand content(R^2= 0.913). The geometric mean diameter of soil particles had a negative correlation with D_1(R^2= 0.569) and D_2(R^2= 0.682). Semivariograms of fractal dimensions and soil textural parameters were calculated and the maps of spatial variation of D_1 and D_2 and soil PSD parameters were provided using ordinary kriging. The results showed that there were also spatial correlations between D_1 and D_2 and particle size fractions.According to the semivariogram models and validation parameters, the fractal parameters had powerful spatial structure and could better describe the spatial variability of soil texture.
