Characterisation of permanent deformation behaviour of unbound granular materials using repeated load triaxial testing
- Authors: Zhalehjoo, Negin , Tolooiyan, Ali , Mackay, Rae , Bodin, Didier
- Date: 2018
- Type: Text , Conference proceedings
- Relation: 10th International Conference on the Bearing Capacity of Roads, Railways and Airfields, BCRRA 2017; Athens, Greece; 28th-30th June 2017; published in Bearing Capacity of Roads, Railways and Airfields p. 159-166
- Full Text: false
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- Description: Unbound Granular Material (UGM) used in the base/subbase layers of a flexible pavement structure constitutes the vast majority of the material found in roads around the world. The permanent deformation of a compacted UGM layer due to cyclic deviatoric loading has a significant effect on the performance of the pavement structure. The accurate prediction of the magnitude of accumulated permanent strain at varying load cycles and stress levels plays an important role in improving the design and maintenance of flexible pavements. In this study, samples of two road base UGMs are tested to evaluate the characteristics of permanent deformation using the laboratory Repeated Load Triaxial (RLT) test. Three permanent deformation models are used to predict the magnitude of strain accumulation of the studied UGMs. The permanent strain results predicted by the models are compared against those measured by laboratory RLT tests to evaluate the prediction ability of each model.
- Description: Bearing Capacity of Roads, Railways and Airfields - Proceedings of the 10th International Conference on the Bearing Capacity of Roads, Railways and Airfields, BCRRA 2017
Elucidating the impact of micro-scale heterogeneous bacterial distribution on biodegradation
- Authors: Schmidt, Susanne , Kreft, Jan-Ulrich , Mackay, Rae , Picioreanu, Cristian , Thullner, Martin
- Date: 2018
- Type: Text , Journal article
- Relation: Advances in Water Resources Vol. 116, no. (2018), p. 67-76
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- Description: Groundwater microorganisms hardly ever cover the solid matrix uniformly–instead they form micro-scale colonies. To which extent such colony formation limits the bioavailability and biodegradation of a substrate is poorly understood. We used a high-resolution numerical model of a single pore channel inhabited by bacterial colonies to simulate the transport and biodegradation of organic substrates. These high-resolution 2D simulation results were compared to 1D simulations that were based on effective rate laws for bioavailability-limited biodegradation. We (i) quantified the observed bioavailability limitations and (ii) evaluated the applicability of previously established effective rate concepts if microorganisms are heterogeneously distributed. Effective bioavailability reductions of up to more than one order of magnitude were observed, showing that the micro-scale aggregation of bacterial cells into colonies can severely restrict the bioavailability of a substrate and reduce in situ degradation rates. Effective rate laws proved applicable for upscaling when using the introduced effective colony sizes.
The effect of instrumentation on the determination of the resilient modulus of unbound granular materials using advanced repeated load triaxial testing
- Authors: Zhalehjoo, Negin , Tolooiyan, Ali , Mackay, Rae , Bodin, Didier
- Date: 2018
- Type: Text , Journal article
- Relation: Transportation Geotechnics Vol. 14, no. (2018), p. 190-201
- Full Text: false
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- Description: Unbound Granular Materials (UGMs) are used in the base/subbase layers of flexible pavement structures for the vast majority of the main roads around the world. The resilient modulus of UGMs is a key input parameter for the design and analysis of flexible pavement structures. In the present study, four road base UGMs with a range of moisture contents are used to evaluate each material's resilient deformation behaviour using laboratory repeated load triaxial tests. The triaxial system for the tests is instrumented with four axial deformation gauges: an on-specimen axial Hall-Effect transducer, an internal Linear Variable Differential Transformer (LVDT), an external LVDT, and the actuator LVDT. The application of a Hall-Effect transducer directly mounted on the specimen and the three LVDTs permits the comparative study of alternative deformation measurements for the determination of an accurate and reliable resilient modulus value. By comparing tests results obtained with each transducer, the relative capability of each measurement is determined and a reference transducer for deformation measurement is identified. A constitutive model is then used to carry out a regression analysis and to predict the resilient modulus of the four tested materials.
Understanding deep aquifer responses to interseam materials of brown coal mines
- Authors: Rastogi, Sid , Barton, Andrew , Mackay, Rae , Kandra, Harpreet , Tolooiyan, Ali
- Date: 2018
- Type: Text , Conference proceedings , Conference paper
- Relation: 2018 Hydrology and Water Resources Symposium: Water and Communities, HWRS 2018; Melbourne, Australia; 3rd-6th December 2018 p. 711-722
- Full Text: false
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- Description: Brown coal deposits in the Latrobe Valley form part of the tertiary coal system of the Gippsland Basin, which is one of three major tertiary basins in Victoria, Australia. There are currently two operating brown coal mines in the Latrobe Valley (Yallourn and Loy Yang Mines) where coal is mined for power generation, with a third mine (Hazelwood) having recently ceased operations. An ongoing challenge in the mines is the management of geotechnical stability of the open pit batters. This includes the management of significant issues such as instability due to floor heave which is directly related to groundwater pressures of the underlying confined aquifers. The time dependent pressure distributions in the interseam layers are complex due to the complex heterogeneous stratigraphy of these layers. A model of the fine scale stratigraphy using Minescape has been developed to explore how pressure redistribution occurs and how the groundwater flow systems impact the interseam pore pressures due to pumping activity, leading to potential impacts on the mine batter movements. The objective of the preliminary groundwater modelling presented in this paper is to examine the hydraulic connectivity between the lower pumped aquifer layers and the upper sandy layers. The goal is to assess whether the connections are solely through vertical flows through the interbedded aquitard layers or whether there are lateral connections of the sandy layers that govern the vertical connections. A one-dimensional vertical flow model has been used for this purpose in conjunction with high quality groundwater head data from multiple depths in vertically sealed bores. The results suggest that the pressure redistributions vertically cannot be explained by vertical flows alone and that lateral exchange between layers is also occurring. This work will inform the next stage of modelling that will use the detailed stratigraphic modelling in three dimensions.
Unconfined Expansion Test (UET) for measuring the tensile strength of organic soft rock
- Authors: Tang, Zhan , Tolooiyan, Ali , Mackay, Rae
- Date: 2017
- Type: Text , Journal article
- Relation: Computers and Geotechnics Vol. 82, no. (2017), p. 54-66
- Full Text: false
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- Description: An Unconfined Expansion Test (UET) is presented for measuring the tensile strength of Intermediate Geotechnical Materials (IGM). The test is performed by generating radial cavity expansion inside a cylindrical specimen. Pressure redistributes evenly around the cavity wall during the test. Tensile failure initiates on the weakest plane around the cavity and radially propagates across the specimen. By also capturing the stress-strain relationship and deriving the shear modulus, a UET is also capable of measuring the tensile elastic modulus of the material. An eXtended Finite Element Method (XFEM) analysis using Abaqus/Standard has been carried out to verify the UET test results. © 2016 Elsevier Ltd
Effects of recycled aggregate growth substrate on green roof vegetation development: A six year experiment
- Authors: Bates, Adam , Sadler, Jon , Greswell, Richard , Mackay, Rae
- Date: 2015
- Type: Text , Journal article
- Relation: Landscape and Urban Planning Vol. 135, no. (2015), p. 22-31
- Full Text: false
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- Description: Green roofs have the potential to address several of the environmental problems associated with urbanisation, and can be used as mitigation for habitats lost at ground level. Brown roofs (a type of green roof) can be used to mitigate for the loss of brownfield habitat, but the best way of designing these habitats remains unclear. This paper reports an experiment to test the effects of different types of recycled aggregate on the development of vegetation assemblages on brown roof mesocosms. Five recycled aggregates were tested: (1) crushed brick, (2) crushed demolition aggregate, (3) solid municipal waste incinerator bottom ash aggregate, (4) a 1:1 mix of 1 and 2, and (5) a 1:1 mix of 3 and 2. Each was seeded with a wildflower mix that also included some Sedum acre and vegetation development was studied over a six-year period. Species richness, assemblage character, number of plants able to seed, and plant biomass were measured. Drought disturbance was the key factor controlling changes in plant assemblage, but effects varied with substrate treatment. All treatments supported a similar plant biomass, but treatments with a high proportion of crushed brick in the growth substrate supported richer assemblages, with more species able to seed, and a smaller amount of Sedum acre. Crushed brick, or recycled aggregates with a high proportion of crushed brick, are recommended as good growth substrate materials for encouraging brown roof plant diversity. This investigation demonstrates the importance of multi-year studies of green roof development for the generation of robust findings.
Effects of varying organic matter content on the development of green roof vegetation: A six year experiment
- Authors: Bates, Adam , Sadler, Jon , Greswell, Richard , Mackay, Rae
- Date: 2015
- Type: Text , Journal article
- Relation: Ecological Engineering Vol. 82, no. September (2015), p. 301-310
- Full Text: false
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- Description: Green roofs can potentially be used to tackle a variety of environmental problems, and can be used as development mitigation for the loss of ground-based habitats. Brown (biodiversity) roofs are a type of green roof designed to imitate brownfield habitat, but the best way of engineering these habitats requires more research. We tested the effects of altering organic matter content on the development of vegetation assemblages of experimental brown (biodiversity) roof mesocosms. Three mulch treatments were tested: (1) sandy loam, where 10 mm of sandy loam mulch (about 3% organic matter by dry weight) was added to 100 mm of recycled aggregate; (2) compost, where the mulch also contained some garden compost (about 6% organic matter by dry weight); and (3) no mulch, where no mulch was added. Mesocosms were seeded with a wildflower mix that included some Sedum acre, and vegetation development was investigated over a six-year period. Species richness, assemblage character, number of plants able to seed, and above-ground plant biomass were measured. Drought disturbance was an important control on plant assemblages in all mulch treatments, but there were significant treatment response interactions. The more productive compost treatment was associated with larger plant coverage and diversity before the occurrence of a sequence of drought disturbances, but was more strongly negatively affected by the disturbances than the two less productive treatments. We suggest that this was due to the over-production of plant biomass in the more productive treatment, which made the plants more vulnerable to the effects of drought disturbance, leading to a kind of 'boom-bust' assemblage dynamic. The 'ideal' amount of added organic matter for these green roof systems was very low, but other types of green roof that have a larger water holding capacity, and/or more drought resistant plant floras, will likely require more organic matter or fertiliser. Nonetheless, nutrient-supported productivity in green roof systems should be kept low in order to avoid boom-bust plant assemblage dynamics. Research into the best way of engineering green roof habitats should take place over a long enough multi-year time period to include the effects of temporally infrequent disturbances. © 2015 Elsevier B.V.
Creep due to chemical alteration of rocks - A Case study in brown coal
- Authors: Mackay, Rae , Wight, B. J. , Kim, Sungho
- Date: 2014
- Type: Text , Conference paper
- Relation: AusRock 2014: Third Australasian Ground Control in Mining Conference p. 61-64
- Full Text: false
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Experimental study of brown coal hydraulic behavior at low confining stress
- Authors: Liu, Kan , Mackay, Rae , Xue, Jianfeng , Tolooiyan, Ali
- Date: 2014
- Type: Text , Conference paper
- Relation: 6th International Conference on Unsaturated Soils p. 1125-1130
- Full Text: false
- Reviewed:
- Description: The hydraulic behavior of Victorian brown coal has been studied under low pressure confining conditions. A triaxial constant head permeameter was constructed to carry out permeability tests under alternative confining conditions. Test results from alternative constant head test methods were found to be different indicating higher than expected internal storage due to the possible existence of gas in the coal matrix and/or compressibility of the coal grains. A conceptual model of brown coal with disconnected gas bubbles was proposed to explain the observed variation of hydraulic behavior. In this model, the compressible gas bubbles are assumed to be trapped between compressible coal particles. A numerical model was developed to gain insights into the hydraulic influence of these factors and the model was used to simulate the test process. Constant hydraulic conductivity was assumed. The results from the model and the tests are found to compare well. The model explains most but not all of the observed behavior.
Measurement of pore water pressure properties of unsaturated brown coal using triaxial test
- Authors: Couling, Catherine Elizaebth , Tolooiyan, Ali , Mackay, Rae , Xue, Jianfeng
- Date: 2014
- Type: Text , Conference paper
- Relation: 6th International Conference on Unsaturated Soils, UNSAT 2014 p. 1531-1535
- Full Text: false
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- Description: Skempton's B parameter characterises the effect of fluid compressibility on the time dependent deformation of materials during isotropic loading. The Skempton B-parameter has been determined for a sample of Victorian brown coal for a range of confining pressures, corresponding to the range of conditions which the coal experiences below the ground water table. The relationship between the change in the B-parameter with respect to time and pressure has also been examined. It has been found that a high back pressure (more than 400 kPa) is required in the material to achieve a degree of saturation close to 100+ACU-. The set of data from these tests is able to provide important evidence of the depth and stress dependent behaviour of the coal.
Measurement of residual shear strength using a modified direct shear apparatus
- Authors: Tatnell, Luke , Tolooiyan, Ali , Mackay, Rae
- Date: 2014
- Type: Text , Conference paper
- Relation: AusRock 2014: Third Australasian Ground Control in Mining Conference p. 425-434
- Full Text: false
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Measurement of the tensile strength of organic soft rock
- Authors: Tolooiyan, Ali , Mackay, Rae , Xue, Jianfeng
- Date: 2014
- Type: Text , Journal article
- Relation: Geotechnical Testing Journal Vol. 37, no. 6 (2014), p.
- Full Text: false
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- Description: Understanding all potential slope failure mechanisms is a pre-requisite for predicting the likelihood of batter movements during excavation in open cut mines. The tensile behavior of soils and rocks may be a significant contributor to a slope failure and must be known in order to quantify the risks of slope failure. The contribution can be particularly significant for Intermediate Geotechnical Materials (IGMs) that possess characteristics of both soils and rocks and where the failure mechanisms are complex due to the interplay between ductile and brittle behavior. Brown coal is such an intermediate Geotechnical Material. Recent batter movements in the brown coal mines in the Latrobe Valley, Australia have raised doubts about the current understanding of the mechanisms of slope failure in this material. Research is underway to re-evaluate all properties of the brown coal applicable to slope failure. This paper describes the investigation of brown coal tensile strength. There are alternative test methods available to determine the tensile behavior of materials, including direct tensile tests, beam bending tests and Brazilian compression tests. The applicability of each test method is material dependent, as such, it is necessary to confirm the validity of the methods for each material. Beam bending tests have achieved mixed results for both rocks and IGMs previously. Thus, the present work has explored only the use of Direct tensile and Brazilian test methods. Both methods were implemented using a modified direct shear apparatus and valid test procedures for both test methods were developed. Each test procedure has been verified by Finite Element Modelling (FEM) using ABAQUS 6.12.1 FEM code. The results from the laboratory test methods are in good agreement and show that brown coal is a predominantly brittle material with a peak tensile strength slightly greater than 100 kPa. The finite element analyses confirm that non-uniformity of the tensile stresses during sample loading tends to lead to the underestimation of tensile strength for both tests, but the Brazilian test has less bias for brown coal. It is observed that the rate of loading of low stiffness, low permeability, and saturated samples in the Brazilian test is an important test design parameter for the accurate determination of tensile strength of IGMs in the laboratory.
Measurement of water pressure properties of unsaturated brown coal using triaxial test
- Authors: Couling, Catherine Elizabeth , Xue, Jianfeng , Tolooiyan, Ali , Mackay, Rae
- Date: 2014
- Type: Text , Conference paper
- Relation: Unsaturated Soils: Research & Applications Vol. 1
- Relation: Proceedings of the 6th International Conference on Unsaturated Soils, UNSAT 2014
- Relation: Sydney, Australia, 2-4 July, 2014
- Full Text: false
- Reviewed:
- Description: Skempton used the B-parameter (see Equation 1) to represent the degree of saturation of a material, such that, B → 0, when the degree of saturation = 0 and, B → 1, when the degree of saturation = 1 Δ Δ Δu B[ (Δ A+ )]σ3 1σ 3 (1) where, Δu is change in pore water pressure, A and B are pore-pressure coefficients, and σ3 and σ1 are minor and major principal stresses.
Impacts of nonuniform flow on estimates of vertical streambed flux
- Authors: Cuthbert, M. , Mackay, Rae
- Date: 2013
- Type: Text , Journal article
- Relation: Water Resources Research Vol. 49, no. 1 (2013), p. 29-28
- Full Text: false
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- Description: [1] The use of inverse one-dimensional (1-D) analytical methods for estimating vertical stream-aquifer exchange flux is now commonplace. However, the application of such simple models can lead to significant errors in estimates of vertical exchange flux where the model assumptions are violated in real systems. An idea that is gaining acceptance in the literature is that the presence of nonvertical flow is such a violation. However, it is shown here that nonvertical flow by itself will not necessarily lead to errors in vertical flux estimation but rather that significant errors can stem from nonuniform (convergent/divergent) flow fields and/or hydrodynamic dispersion even within uniform flow fields. Nonuniform flow may also be expected, in some cases, to create discrepancies between flux estimates made on the basis of vertical head gradient measurements and those made using 1-D analytical heat tracer methods. Significant differences are observed in the estimates of heat-derived fluxes obtained by the amplitude ratio and phase-shift time-series methods when convergent and divergent flows are apparent. Such differences may potentially be used to infer that convergent or divergent flow is occurring and that a 1-D analysis is inappropriate.
Vegetation development over four years on two green roofs in the UK
- Authors: Bates, Adam , Sadler, Jon , Mackay, Rae
- Date: 2013
- Type: Text , Journal article
- Relation: Forestry sciences Vol. 12, no. 1 (2013), p. 98-108
- Full Text: false
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- Description: Carefully designed green roofs have the potential to be used as mitigation for habitats lost at ground level. The development of plant assemblages on two green roofs designed to emulate diverse brownfield habitats (brown roofs), by using recycled demolition aggregate as part of a low-fertility growth substrate, were studied over the first four years of their development. The cover-abundance of flowering plants and habitat structural components (e.g. bare ground, moss) were measured on the Domin-Krajina scale within all identified microhabitats. Drought disturbance was one of the main controlling factors on assemblage development. Annual plants were abundant and successful in the first growth season, and thereafter only re-appeared in any numbers following drought disturbances in subsequent years. Moss and Sedum acre L. increased through the study period until these plants dominated coverage. The cover-abundance of perennial wildflower species was strongly influenced by drought disturbance. The influence of drought disturbance varied between different brown roof microhabitats, with plant assemblages in coarser and less fertile microhabitats more resistant to these disturbances. Observed responses to drought were consistent with the following two hypotheses: (i) Areas of coarse substrate can act as disturbance refugia for plants during drought by helping preserve pockets of water under large clasts and within absorbent materials such as brick. (ii) The plant assemblages living in areas of more fertile substrates, which grow more luxuriantly when water availability is high, are more vulnerable to drought disturbance. Green roofs should be designed to include a range of substrate types to create several microhabitats that will collectively support more species than any single microhabitat.
A new ring shear apparatus for determination of the residual shear resistance of remoulded brown coal
- Authors: Mackay, Rae , Xue, Jianfeng , Powrie, William , Dent, B.
- Date: 2012
- Type: Text , Conference paper
- Relation: p. 79-84
- Full Text: false
- Reviewed:
- Description: Victorian brown coal is a typical intermediate geomaterial, whose behaviour falls between that of soft rock and engineering clay. The intact material exhibits lower permeability and higher tensile strength compared to overconsolidated clay. Large, shallow open cuts are used to mine the coal in the Latrobe Valley, Victoria, Australia, predominantly as fuel for Victoria's power stations. For batter design the brown coal is treated as clay with high values of cohesion and friction angle. Composite rotational and block sliding is a recognised failure mode for this material and it is apparent from recent observations that failure risk increases with time. During long-term movements of the brown coal behind and below the batters it is anticipated that the material will be crushed and remoulded along sliding surfaces as a result of progressive pre-failure displacements. After periods of decades, the assumption is that for large sections along any incipient failure surface, shear strength will be at or close to the residual shear strength of the material. Thus, it is important to understand whether this assertion is correct and the processes leading to the weakened state. A new ring-shear test apparatus has been designed to determine the variation of shear strength of this material for a range of shear strains under essentially drained conditions. In this paper the design considerations and the resulting form of the test apparatus are presented. The equipment is also applicable to the testing of the interseam clays, silts and fine sands that are also found in the mines.
Controls on the rate of ureolysis and the morphology of carbonate precipitated by S. Pasteurii biofilms and limits due to bacterial encapsulation
- Authors: Cuthbert, M. , Riley, Michael , Handley-Sidhu, Stephanie , Renshaw, Joanna , Tobler, Dominique , Phoenix, Vernon , Mackay, Rae
- Date: 2012
- Type: Text , Journal article
- Relation: Ecological Engineering Vol. 41, no. (2012), p. 32-40
- Full Text: false
- Reviewed:
- Description: Despite the potential contribution of microbially induced carbonate precipitation (MICP) to a range of environmental technologies, little is known about the controls on the rate of ureolysis and precipitate size and morphology using attached bacterial communities. This paper presents results of experiments using Sporosarcina pasteurii biofilms, of varying density, grown on perspex and granite surfaces then immersed in fluids comprising calcium chloride and urea of varying concentrations. Denser biofilms resulting from higher nutrient conditions led to faster nucleation of calcite and higher rates of ammonium production found to be related to crystal size via a power law. The observed morphology of the precipitates was variable depending on precipitation rates and nucleation of calcite was independent of the substrate mineralogy. In some cases the calcite layer became non-porous, and the bridging of pores within the granite was also observed. We show how ureolysis is limited eventually by the encapsulation of the biofilm by calcite and present a novel model that enables the reaction to be optimised to yield maximum calcite precipitation over a desired timescale. Slower reaction rates may in some circumstances be desirable for maximum reaction efficiency. The results have important implications for the design of engineering solutions involving MICP
Evaluation of simple beam experiments to determine the long-term deformation characteristics of brown coal
- Authors: Dent, B. , Mackay, Rae
- Date: 2012
- Type: Text , Conference paper
- Relation: 11th Australia - New Zealand Conference on Geomechanics: Ground Engineering in a Changing World p. 914-919
- Full Text: false
- Reviewed:
- Description: 0905 Civil Engineering
Linking soil moisture balance and source-responsive models to estimate diffuse and preferential components of groundwater recharge
- Authors: Cuthbert, M. , Mackay, Rae , Nimmo, J.
- Date: 2012
- Type: Text , Journal article
- Relation: Hydrology and Earth System Sciences Discussions Vol. 9, no. 7 (2012), p. 8455-8492
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- Description: Results are presented of a detailed study into the vadose zone and shallow water table hydrodynamics of a field site in Shropshire, UK. A conceptual model is developed and tested using a range of numerical models, including a modified soil moisture balance model (SMBM) for estimating groundwater recharge in the presence of both diffuse and preferential flow components. Tensiometry reveals that the loamy sand topsoil wets up via macropore flow and subsequent redistribution of moisture into the soil matrix. Recharge does not occur until near-positive pressures are achieved at the top of the sandy glaciofluvial outwash material that underlies the topsoil, about 1 m above the water table. Once this occurs, very rapid water table rises follow. This threshold behaviour is attributed to the vertical discontinuity in the macropore system due to seasonal ploughing of the topsoil, and a lower permeability plough/iron pan restricting matrix flow between the topsoil and the lower outwash deposits. Although the wetting process in the topsoil is complex, a SMBM is shown to be effective in predicting the initiation of preferential flow from the base of the topsoil into the lower outwash horizon. The rapidity of the response at the water table and a water table rise during the summer period while flow gradients in the unsaturated profile were upward suggest that preferential flow is also occurring within the outwash deposits below the topsoil. A variation of the source-responsive model proposed by Nimmo (2010) is shown to reproduce the observed water table dynamics well in the lower outwash horizon when linked to a SMBM that quantifies the potential recharge from the topsoil. The results reveal new insights into preferential flow processes in cultivated soils and provide a useful and practical approach to accounting for preferential flow in studies of groundwater recharge estimation.
A multi-scale agent-based distributed simulation framework for groundwater pollution management
- Authors: Schmidt, Susanne , Picioreanu, Cristian , Craenen, Bart , Mackay, Rae , Kreft, Jan-Ulrich , Theodoropoulos, Georgios
- Date: 2011
- Type: Text , Conference paper
- Full Text: false
- Reviewed:
- Description: Groundwater is like dark matter - we know very little apart from the fact that it is hugely important. Given the scarcity of data, mathematical modelling can come to the rescue but existing groundwater models are mainly restricted to simulate the transport and degradation of contaminants on the scale of whole contaminated field sites by averaging out the effect of spatial heterogeneity on the availability of the pollutant to the degrading organisms. These coarse-scale mean-field models therefore tend to rely on fitting to data rather than being predictive. Also, they are less suited to incorporate spatial variability and non-linear kinetics and feedbacks. We propose to solve the two mutually exacerbating problems of environmental patchiness and data scarcity by developing a flexible and robust distributed simulation framework that uses an ensemble of small scale simulations running on different processors/computers to scale-up, i.e. to feed the effect of small-scale patchiness into a concurrent site-scale simulation of the dynamics of groundwater pollutant degradation. Our scaling approach solves problem #1 by simulating dynamics also on the small scale where some of the patchiness resides, and problem #2 by enabling rigorous validation of our small-scale model and scaling approach with laboratory data, which are high quality at low cost.
- Description: 2014061150