Analytical and numerical models for evaluation of tunnel excavation stability in a multi layered soil profile with groundwater flow

2017 ◽  
pp. 223-232
Author(s):  
L.E. Sozio
Keyword(s):  
Groundwater Flow ◽  
Soil Profile ◽  
Numerical Models ◽  
Layered Soil ◽  
Tunnel Excavation ◽  
Excavation Stability

scholarly journals A model ensemble generator to explore structural uncertainty in karst systems with unmapped conduits

2020 ◽  
Author(s):  
Chloé Fandel ◽  
Ty Ferré ◽  
Zhao Chen ◽  
Philippe Renard ◽  
Nico Goldscheider
Keyword(s):  
Data Collection ◽  
Groundwater Flow ◽  
Spatial Information ◽  
Numerical Models ◽  
Flow Behavior ◽  
Spring Discharge ◽  
Generation Process ◽  
Model Ensemble ◽  
Long Term Study ◽  
Conduit Networks

Abstract Karst aquifers are characterized by high-conductivity conduits embedded in a low-conductivity fractured matrix, resulting in extreme heterogeneity and variable groundwater flow behavior. The conduit network controls groundwater flow, but is often unmapped, making it difficult to apply numerical models to predict system behavior. This paper presents a multi-model ensemble method to represent structural and conceptual uncertainty inherent in simulation of systems with limited spatial information, and to guide data collection. The study tests the new method by applying it to a well-mapped, geologically complex long-term study site: the Gottesacker alpine karst system (Austria/Germany). The ensemble generation process, linking existing tools, consists of three steps: creating 3D geologic models using GemPy (a Python package), generating multiple conduit networks constrained by the geology using the Stochastic Karst Simulator (a MATLAB script), and, finally, running multiple flow simulations through each network using the Storm Water Management Model (C-based software) to reject nonbehavioral models based on the fit of the simulated spring discharge to the observed discharge. This approach captures a diversity of plausible system configurations and behaviors using minimal initial data. The ensemble can then be used to explore the importance of hydraulic flow parameters, and to guide additional data collection. For the ensemble generated in this study, the network structure was more determinant of flow behavior than the hydraulic parameters, but multiple different structures yielded similar fits to the observed flow behavior. This suggests that while modeling multiple network structures is important, additional types of data are needed to discriminate between networks.

Evaporation from homogeneous and heterogeneous soil systems: Modeling approaches and experimental data

2020 ◽  
Author(s):  
Shmuel Assouline ◽  
Tamir Kamai
Keyword(s):  
Experimental Data ◽  
Soil Profile ◽  
Numerical Models ◽  
Water Losses ◽  
Ongoing Research ◽  
Fundamental Limitations ◽  
Soil Systems ◽  
Heterogeneous Soil ◽  
The Impact ◽  
Numerical Approaches

<p>Accurate estimates of water losses from the soil by evaporation are important for hydrological, agricultural, and climatic purposes. Different analytical and numerical approaches were developed to provide the capability to simulate and predict the dynamics of the evaporation process in terms of fluxes, and water and thermal distributions in the soil profile. Experimental investigation of the process under different boundary conditions is also possible by means of columns and weighing lysimeters. As part, these experimental setups allow addressing the impact of heterogeneity in the drying soil profile. Experimental data resulting from evaporation experiments under natural and laboratory conditions with homogeneous and heterogeneous soil profiles are presented and analyzed. These data are also compared to results from available analytical and numerical models. This comparison points out fundamental limitations of the approaches that assume hydraulic connectivity up to the surface, as well as those that suppose monotonic drying when unsteady conditions prevail. Differences between experimental data and model prediction emphasize challenging knowledge gaps that are part of ongoing research.</p>

Centrifuge Testing on Suction Anchors: Double-Wall, Over-Consolidated Clay, and Layered Soil Profile

2006 ◽  
Author(s):  
P. Jeanjean ◽  
D. Znidarcic ◽  
R. Phillips ◽  
H. -Y. Ko ◽  
S. Pfister ◽  
...  
Keyword(s):  
Soil Profile ◽  
Layered Soil ◽  
Centrifuge Testing ◽  
Double Wall

Simulation of carrier-facilitated transport of phenanthrene in a layered soil profile

2002 ◽  
Vol 56 (3-4) ◽  
pp. 209-225 ◽  
Author(s):  
Alexander Prechtel ◽  
Peter Knabner ◽  
Eckhard Schneid ◽  
Kai Uwe Totsche
Keyword(s):  
Soil Profile ◽  
Facilitated Transport ◽  
Layered Soil

A Simple Approach for Estimating the First Resonance Peak of Layered Soil Profiles

2018 ◽  
Vol 12 (01) ◽  
pp. 1850005 ◽  
Author(s):  
Haizhong Zhang ◽  
Yan-Gang Zhao
Keyword(s):  
Soil Profile ◽  
Single Layer ◽  
Resonance Peak ◽  
Layered Soil ◽  
Soil Profiles ◽  
Simple Method ◽  
Amplification Ratio ◽  
Local Site ◽  
The One ◽  
Input Motion

The first resonance peak, Gs1, represents the amplification ratio of seismic motion when resonance between input motion and the local site occurs. The Gs1 is important for understanding amplification characteristics of local site, thus it has been adopted for evaluating site effects in the Japanese Seismic Code. Herein, a simple method for estimating the Gs1 of layered soil profiles is proposed. By replacing a multi-layer soil profile on bedrock with an equivalent one-layer soil profile, the Gs1 and fundamental period are easily obtained. To realize the one-layer profile, we develop a procedure to replace a two-layer soil profile on bedrock with an equivalent single-layer profile. This procedure is then applied successively to a multi-layer soil profile to obtain an equivalent single-layer soil profile. The validity of the proposed method is demonstrated by evaluating 67 representative sites. The results obtained using the proposed procedure agree well with those produced by the wave propagation method.

scholarly journals Digitalization of hydrogeological processes in mining industry

2020 ◽  
pp. 95-100
Author(s):  
E. V. Leontieva ◽  
◽  
V. N. Kvachev ◽  
Keyword(s):  
Groundwater Flow ◽  
Pore Pressure ◽  
Information Technologies ◽  
Numerical Models ◽  
Control Point ◽  
Mining Industry ◽  
Drainage Water ◽  
Anthropogenic Activity ◽  
Influence Zone ◽  
Flow Gradients

The groundwater monitoring reconstruction and hydrogeological digitalization are discussed on the ground of the past and modern mine flooding protection technologies and geo-information technologies. According to the authors, it is of the current concern to advance digitalization technologies for hydrogeological processes in the mining industry to be focused on: – operative and episodic control and display of water condition at the control point in the x, y, z, t coordinates, including pore pressure, temperature, mineralization, flow rate of drainage water intake devices, productivity of pumping equipment of mine and quarry drainage, water-development in pit walls, in underground mines, in the influence zone of mining production; – creation of permanent hydrogeological models of groundwater flow, pore pressure distribution, flow gradients and transport of pollutants within the framework of conceptual and numerical models of subsoil, mining facilities, terrain, natural environment and anthropogenic activity in the influence zone of mining. The article discusses the working cycles of digitalization of operational and occasional monitoring data on the status of groundwater at the control points and 3D representations of groundwater flow, distribution of pore pressure, pressure gradients and movement of pollutants using constantly operating models to ensure safe and competitive development of flooded mineral deposits in modern conditions. The relevance of the digitalization technologies for hydrogeological processes based on the latest achievements in the field of geoinformatics and automation of hydrogeological work is substantiated.

scholarly journals Modeling groundwater flow and salinity evolution near TSF Żelazny Most. Part I – groundwater flow

2018 ◽  
Vol 54 ◽  
pp. 00036
Author(s):  
Waldemar Świdziński
Keyword(s):  
Numerical Model ◽  
Groundwater Flow ◽  
Chloride Transport ◽  
Numerical Models ◽  
General Information ◽  
Water Mixture ◽  
Groundwater Environment ◽  
Gold Silver ◽  
Copper Gold ◽  
System Part

Tailings which are by-product of the extraction of various metals (copper, gold, silver, molybdenum, etc.) are often stored in so called Tailings Storage Facilities (TSF), where they are deposited as a soil-water mixture by spigotting. In many cases the water discharged together with tailings to the TSF is rich in salts and other chemical compounds imposing negative pressure to the groundwater environment. Even in the case of total or partial lining of such facilities and well-developed drainage systems to control leaching, some portion of contaminated water often seeps either through the surrounding dams or the bed into adjacent groundwater bodies. Numerical models can be very helpful tools to assess the extent of the contamination and particularly to predict its potential development in the future. This paper and the companion one describe such a numerical model developed for Żelazny Most Tailings Storage Facility (south-west Poland), one of the world’s largest tailings sites. In the first part general information about the facility is provided and a 3D hydrogeological numerical model of the structure is described. Groundwater flow pattern near the facility obtained from numerical simulations is confronted with the measurements from a comprehensively developed monitoring system. Part II will be focused on the modelling of chloride transport in groundwater.

Sign in / Sign up

Export Citation Format

Share Document