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The numerical simulation of water-salt movement in soil with vegetation (in Chinese)
PROPERTIESDEFORMATION 967072
The numerical simulation of water-salt movement in soil with vegetation (in Chinese) Chen Qisheng & Qi Longxi, Shuili XuebaojJournal of Hydraulic Engineering, 1, 1996, pp 38-46. A modified Picard iteration method is applied to solve the mixed form of the Richards equation for water movement in saturated-unsaturated soil. The mass balance error in this algorithm is far less than that in the traditional procedure. The characteristic difference method is used to solve the convection-dispersion equation for salt movement, in order to avoid the numerical diffusion and oscillation. Finally, this model is used to simulate water-salt movement in soil under the conditions of vegetation covering, rainfall irrigation and evaporation. This enables the quantitative explanation of the soil salinization as well as long and middle term prediction of dynamic behavior of soil salt. (from English summary) 967073 Geographic Information System (GE) database development for the central Passaic River Basin hydrogeologic investigation M. A. French, Open File Report - New Jersey Geological Survey, 95-2, 1995, 31 pp. The development of a Geographic Information System (GIS) database accompanied the Central Passaic River Basin Hydrogeologic Investigation (Passaic Study). This database provided data for use in the three-dimensional, fmitedifference ground-water model, MODFLOW. A short discussion of ground-water flow, the ground-water-flow model and the ARC/INFO GIS is included. The content of each GIS coverage in the database is listed and described. The development of the model grid, the loading of the grid, its integration with the finite difference ground-water model, and the treatment of the model’s results are outlined. This report discusses some of the problems encountered in creating the database and recommends possible solutions and improvements to the GIS finite-difference-model integration process. (Author)
PROPERTIES SOILS
OF ROCKS AND
General 967074
The soil freezing characteristic: its measurement and similarity to the soil moisture characteristic E. J. A. Spaans & J. M. Baker, Soil Science Society of America Journal, 60(l), 1996, pp 13-19. A soil freezing characteristic (SFC) represents the relationship between the quantity and the energy status of liquid water in frozen soil. The SFC is the analogue to the soil moisture characteristic (SMC) and is essential to modeling the transport of water, heat, and solutes in frozen soil. This paper presents a new, automated technique to measure an SFC in situ. It is proposed that water retention properties at high matric potentials are best obtained from draining and at low matric potentials from freezing. (from Authors) 967075
Designing of composition of bentonite-cement slurry for cut-off walls constructed bv the monouhase method L. Rafalski, Archives of Hidroengineeiing & Environmental Mechanics, 41(3-4), 1994, pp 7-23. To reduce the influence of mining waste on ground and river water, two cut-offs have been completed in recent years in Poland. A bentonite cement slurry was applied to both cutoffs. The monophase cut-off construction process was possible by application of a sodium salt mix to modify the properties of the slurry. The paper presents the results of investigations performed to determine the procedure of designing the slurry composition. The relationship between
& STRENGTH
compressive strength and cement to bentonite ratio has been estimated. (from Author)
Composition, density
structure,
texture and
967076
Self-similitude and fractal dimension of sand grains P. Barak, C. A. Seybold & K. McSweeney, Soil Science Society of America Journal, 60(l), 1996, pp 72-76. Fractal theory postulates that geological materials possess a noninteger, fractal dimension describing length-surfacevolume relations and particle-size distribution. The authors examined sand grains, composed largely of quartz, from several horizons of Wisconsin soils derived from glacial outwash for fractal dimension using image analysis of reflected light micrographs with NIH Image software. No evidence was found to support other than a Euclidean, i.e., regular dimension. Fractal theory would not appear to provide a useful description for these soil materials. (from Authors) 967077 Qualitative and quantitative analysis of microstructures in Polish glacial tills with respect to their age J. Trzcinski, Kwartalnik Geologiczny, 39(3), 1995, pp 403421. A new method has been applied in the course of analysis of glacial tills, in areas glaciated during the North Polish, Middle Polish, and South Polish Glaciations. The method has not yet been commonly employed for assessing engineeringgeological characteristics of soils. This study has allowed for the determination of matrix microstructure most common in glacial tills. Among all tills in Poland the youngest tills have maximum porosity, but contacts and structural ties in these tills are loose. The older the glacial tills, the less porosity and closer contacts and ties they have. (Author)
Deformation and strength characteristics 967078
Properties of marble as building veneer E. M. Winkler, International Journal of Rock Mechanics & Mining Sciences, 33(2), 1996, pp 215-218. The anomalous expansion-contraction behaviour of crystalline calcite marble combined with the release of locked-in residual stresses may result in considerable strains responsible for bowing by expansion. Laboratory tests with Carrara marble support the observations limited to the Amoco Building. Similar cases of warping have been discussed by some other authors. It is thought that moisture is important in the bowing process. Here the role of moisture is discussed which is instrumental for both concave (inward) and convex (outward) warping, also warping of granite panels. (from Author) 967079 Probe microphone instrumentation for determining soil physical properties: testing in model porous materials J. M. Sabatier, D. C. Sokol, C. K. Frederickson, M. J. M. Romkens, E. H. Grissinger & J. C. Shipps, Soil Technology, 8(4), 1996, pp 259-274. An acoustic technique for evaluating soil physical properties is described and tested in model porous materials. A probe microphone is used to measure the acoustic signal attenuation and phase speed. Emphasis is on the probe construction, insertion in soils and reduction of acoustic data to predict tortuosity and an effective air-flow resistivity of the soil. Measurements in three materials: glass beads, washed sand and loess soil are analyzed and discussed. The instrumentation works well in the glass beads and washed sand tested;
The numerical simulation of water-salt movement in soil with vegetation (in Chinese) Chen Qisheng & Qi Longxi, Shuili XuebaojJournal of Hydraulic Engineering, 1, 1996, pp 38-46. A modified Picard iteration method is applied to solve the mixed form of the Richards equation for water movement in saturated-unsaturated soil. The mass balance error in this algorithm is far less than that in the traditional procedure. The characteristic difference method is used to solve the convection-dispersion equation for salt movement, in order to avoid the numerical diffusion and oscillation. Finally, this model is used to simulate water-salt movement in soil under the conditions of vegetation covering, rainfall irrigation and evaporation. This enables the quantitative explanation of the soil salinization as well as long and middle term prediction of dynamic behavior of soil salt. (from English summary) 967073 Geographic Information System (GE) database development for the central Passaic River Basin hydrogeologic investigation M. A. French, Open File Report - New Jersey Geological Survey, 95-2, 1995, 31 pp. The development of a Geographic Information System (GIS) database accompanied the Central Passaic River Basin Hydrogeologic Investigation (Passaic Study). This database provided data for use in the three-dimensional, fmitedifference ground-water model, MODFLOW. A short discussion of ground-water flow, the ground-water-flow model and the ARC/INFO GIS is included. The content of each GIS coverage in the database is listed and described. The development of the model grid, the loading of the grid, its integration with the finite difference ground-water model, and the treatment of the model’s results are outlined. This report discusses some of the problems encountered in creating the database and recommends possible solutions and improvements to the GIS finite-difference-model integration process. (Author)
PROPERTIES SOILS
OF ROCKS AND
General 967074
The soil freezing characteristic: its measurement and similarity to the soil moisture characteristic E. J. A. Spaans & J. M. Baker, Soil Science Society of America Journal, 60(l), 1996, pp 13-19. A soil freezing characteristic (SFC) represents the relationship between the quantity and the energy status of liquid water in frozen soil. The SFC is the analogue to the soil moisture characteristic (SMC) and is essential to modeling the transport of water, heat, and solutes in frozen soil. This paper presents a new, automated technique to measure an SFC in situ. It is proposed that water retention properties at high matric potentials are best obtained from draining and at low matric potentials from freezing. (from Authors) 967075
Designing of composition of bentonite-cement slurry for cut-off walls constructed bv the monouhase method L. Rafalski, Archives of Hidroengineeiing & Environmental Mechanics, 41(3-4), 1994, pp 7-23. To reduce the influence of mining waste on ground and river water, two cut-offs have been completed in recent years in Poland. A bentonite cement slurry was applied to both cutoffs. The monophase cut-off construction process was possible by application of a sodium salt mix to modify the properties of the slurry. The paper presents the results of investigations performed to determine the procedure of designing the slurry composition. The relationship between
& STRENGTH
compressive strength and cement to bentonite ratio has been estimated. (from Author)
Composition, density
structure,
texture and
967076
Self-similitude and fractal dimension of sand grains P. Barak, C. A. Seybold & K. McSweeney, Soil Science Society of America Journal, 60(l), 1996, pp 72-76. Fractal theory postulates that geological materials possess a noninteger, fractal dimension describing length-surfacevolume relations and particle-size distribution. The authors examined sand grains, composed largely of quartz, from several horizons of Wisconsin soils derived from glacial outwash for fractal dimension using image analysis of reflected light micrographs with NIH Image software. No evidence was found to support other than a Euclidean, i.e., regular dimension. Fractal theory would not appear to provide a useful description for these soil materials. (from Authors) 967077 Qualitative and quantitative analysis of microstructures in Polish glacial tills with respect to their age J. Trzcinski, Kwartalnik Geologiczny, 39(3), 1995, pp 403421. A new method has been applied in the course of analysis of glacial tills, in areas glaciated during the North Polish, Middle Polish, and South Polish Glaciations. The method has not yet been commonly employed for assessing engineeringgeological characteristics of soils. This study has allowed for the determination of matrix microstructure most common in glacial tills. Among all tills in Poland the youngest tills have maximum porosity, but contacts and structural ties in these tills are loose. The older the glacial tills, the less porosity and closer contacts and ties they have. (Author)
Deformation and strength characteristics 967078
Properties of marble as building veneer E. M. Winkler, International Journal of Rock Mechanics & Mining Sciences, 33(2), 1996, pp 215-218. The anomalous expansion-contraction behaviour of crystalline calcite marble combined with the release of locked-in residual stresses may result in considerable strains responsible for bowing by expansion. Laboratory tests with Carrara marble support the observations limited to the Amoco Building. Similar cases of warping have been discussed by some other authors. It is thought that moisture is important in the bowing process. Here the role of moisture is discussed which is instrumental for both concave (inward) and convex (outward) warping, also warping of granite panels. (from Author) 967079 Probe microphone instrumentation for determining soil physical properties: testing in model porous materials J. M. Sabatier, D. C. Sokol, C. K. Frederickson, M. J. M. Romkens, E. H. Grissinger & J. C. Shipps, Soil Technology, 8(4), 1996, pp 259-274. An acoustic technique for evaluating soil physical properties is described and tested in model porous materials. A probe microphone is used to measure the acoustic signal attenuation and phase speed. Emphasis is on the probe construction, insertion in soils and reduction of acoustic data to predict tortuosity and an effective air-flow resistivity of the soil. Measurements in three materials: glass beads, washed sand and loess soil are analyzed and discussed. The instrumentation works well in the glass beads and washed sand tested;