Modeling FEBEX Large-Scale In Situ Test

ABSTRACTThis paper reports the coupled thermo-hydro-mechanical (THM) analyses of the “in situ” test carried out during the pre-operational stage of the FEBEX project. The determination of parameters has been performed using the results of the characterization stage and other available information. The results of the analyses provide a good understanding of expected test behaviour. This understanding is enhanced by the performance of a quite extensive programme of 1-D sensitivity analyses in which the values of critical parameters are varied. Two dimensional effects are discussed on the basis of the results of 2-D axisymmetric THM analyses carried out using a longitudinal section that provides a better representation of real test geometry.

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Coupled Thermo-Hydro-Geochemical Models of Engineered Barrier Systems: The Febex Project

MRS Proceedings ◽

10.1557/proc-663-561 ◽

2000 ◽

Vol 663 ◽

Cited By ~ 2

Author(s):

J. Samper ◽

R. Juncosa ◽

V. Navarro ◽

J. Delgado ◽

L. Montenegro ◽

...

Keyword(s):

Large Scale ◽

Reference Model ◽

Numerical Models ◽

Full Scale ◽

Small Scale ◽

Model Parameters ◽

In Situ Test ◽

Wide Range ◽

Engineered Barrier

ABSTRACTFEBEX (Full-scale Engineered Barrier EXperiment) is a demonstration and research project dealing with the bentonite engineered barrier designed for sealing and containment of waste in a high level radioactive waste repository (HLWR). It includes two main experiments: an situ full-scale test performed at Grimsel (GTS) and a mock-up test operating since February 1997 at CIEMAT facilities in Madrid (Spain) [1,2,3]. One of the objectives of FEBEX is the development and testing of conceptual and numerical models for the thermal, hydrodynamic, and geochemical (THG) processes expected to take place in engineered clay barriers. A significant improvement in coupled THG modeling of the clay barrier has been achieved both in terms of a better understanding of THG processes and more sophisticated THG computer codes. The ability of these models to reproduce the observed THG patterns in a wide range of THG conditions enhances the confidence in their prediction capabilities. Numerical THG models of heating and hydration experiments performed on small-scale lab cells provide excellent results for temperatures, water inflow and final water content in the cells [3]. Calculated concentrations at the end of the experiments reproduce most of the patterns of measured data. In general, the fit of concentrations of dissolved species is better than that of exchanged cations. These models were later used to simulate the evolution of the large-scale experiments (in situ and mock-up). Some thermo-hydrodynamic hypotheses and bentonite parameters were slightly revised during TH calibration of the mock-up test. The results of the reference model reproduce simultaneously the observed water inflows and bentonite temperatures and relative humidities. Although the model is highly sensitive to one-at-a-time variations in model parameters, the possibility of parameter combinations leading to similar fits cannot be precluded. The TH model of the “in situ” test is based on the same bentonite TH parameters and assumptions as for the “mock-up” test. Granite parameters were slightly modified during the calibration process in order to reproduce the observed thermal and hydrodynamic evolution. The reference model captures properly relative humidities and temperatures in the bentonite [3]. It also reproduces the observed spatial distribution of water pressures and temperatures in the granite. Once calibrated the TH aspects of the model, predictions of the THG evolution of both tests were performed. Data from the dismantling of the in situ test, which is planned for the summer of 2001, will provide a unique opportunity to test and validate current THG models of the EBS.

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TLS and SfM Approach for Bulk Density Determination of Excavated Heterogeneous Raw Materials

Minerals ◽

10.3390/min10020174 ◽

2020 ◽

Vol 10 (2) ◽

pp. 174 ◽

Cited By ~ 5

Author(s):

Peter Blistan ◽

Stanislav Jacko ◽

Ľudovít Kovanič ◽

Julián Kondela ◽

Katarína Pukanská ◽

...

Keyword(s):

Bulk Density ◽

Laser Scanning ◽

Large Scale ◽

Raw Materials ◽

Terrestrial Laser Scanning ◽

Mineral Resources ◽

Point Clouds ◽

Raw Material

A frequently recurring problem in the extraction of mineral resources (especially heterogeneous mineral resources) is the rapid operative determination of the extracted quantity of raw material in a surface quarry. This paper deals with testing and analyzing the possibility of using unconventional methods such as digital close-range photogrammetry and terrestrial laser scanning in the process of determining the bulk density of raw material under in situ conditions. A model example of a heterogeneous deposit is the perlite deposit Lehôtka pod Brehmi (Slovakia). Classical laboratory methods for determining bulk density were used to verify the results of the in situ method of bulk density determination. Two large-scale samples (probes) with an approximate volume of 7 m3 and 9 m3 were realized in situ. 6 point samples (LITH) were taken for laboratory determination. By terrestrial laser scanning (TLS) measurement from 2 scanning stations, point clouds with approximately 163,000/143,000 points were obtained for each probe. For Structure-from-Motion (SfM) photogrammetry, 49/55 images were acquired for both probes, with final point clouds containing approximately 155,000/141,000 points. Subsequently, the bulk densities of the bulk samples were determined by the calculation from in situ measurements by TLS and SfM photogrammetry. Comparison of results of the field in situ measurements (1841 kg∙m−3) and laboratory measurements (1756 kg∙m−3) showed only a 4.5% difference in results between the two methods for determining the density of heterogeneous raw materials, confirming the accuracy of the used in situ methods. For the determination of the loosening coefficient, the material from both large-scale samples was transferred on a horizontal surface. Their volumes were determined by TLS. The loosening coefficient for the raw material of 1.38 was calculated from the resulting values.

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Multilevel Collapsibility of Loess under Irrigation in Jinya Town, Gansu Province, China

Advances in Civil Engineering ◽

10.1155/2019/2153679 ◽

2019 ◽

Vol 2019 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Xiaozhou Zhang ◽

Yudong Lu ◽

Xin Li ◽

Yangchun Lu ◽

Jianzhong Sun ◽

...

Keyword(s):

Large Scale ◽

Engineering Geology ◽

Observation Time ◽

Gansu Province ◽

The Loess Plateau ◽

Infiltration Process ◽

Continuous Irrigation ◽

Two Peaks

The collapsibility of loess has constantly been a major problem in engineering geology. The determination of the collapsibility process and characteristics of loess are crucial to foundation construction and residents’ life in the Loess Plateau. Thus, a large-scale in situ irrigation collapse experiment was conducted on a 10 m2 test pit. A total of 79 benchmarks are used in this experiment. These benchmarks are divided into three categories, namely, deep-buried steel pipe benchmarks, ground benchmarks inside the pit, and ground benchmarks outside the pit. The irrigation and observation time spanned 40 days. In the entire irrigation experiment, a three-day water suspension period resulted in two peaks on the collapsibility velocity curve, thereby showing a remarkable difference in the collapsibility curve from the standard one. In terms of the microstructural deformation types of loess and infiltration process of irrigation water, we found that the collapsibility of loess is a dynamic process apart from being particularly sensitive to water. That is, even after a full collapse of the irrigation process, new pores will eventually form once the water content in the loess begins to decline, thereby providing conditions for another loess collapse. Therefore, multilevel collapsibility can occur during continuous irrigation, which is a problem that has been unexplored in previous applications.

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Quicker Measurement of Walls’ Thermal Resistance Following an Extension to ISO 9869 Average Method

E3S Web of Conferences ◽

10.1051/e3sconf/201911104019 ◽

2019 ◽

Vol 111 ◽

pp. 04019

Author(s):

Arash Rasooli ◽

Laure Itard

Keyword(s):

Heat Flux ◽

Thermal Resistance ◽

Average Method ◽

Large Scale ◽

Accurate Determination ◽

Acceptable Result ◽

Heat Flux Meter ◽

The Difference

Determination of the thermo-physical characteristics of the buildings’ components is crucial to illustrate their thermal behavior and therefore their energy consumption. Along the same line, accurate determination of the thermal resistance of the building walls falls into one the most important targets. Following the difference between in-lab, and on site thermal performance of walls, in-situ measurements have been highly recommended. The most well-known practice for in-situ measurement of walls’ thermal resistance is the Average Method of ISO 9869, using one heat flux meter and two thermocouples. The method, in comparison with other existing methods is quite straight-forward and therefore, is applied widely in large scale. Despite its simplicity, this method usually needs a relatively long time to reach an acceptable result. The current paper deals with a modification to the ISO 9869 method, making it in many situations much quicker than its original state. Through simulation of walls of different typologies, it is shown in which cases the measurement period becomes longer than expected. It is demonstrated how the addition of a heat flux meter to the aforementioned equipment can lead to a much quicker achievement of the thermal resistance, following the rest of the instructions of the standard method.

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Determination of unsaturated hydraulic conductivity taking account of in-situ test

Groundwater Engineering - Recent Advances ◽

10.1201/9781439833605.ch63 ◽

2003 ◽

Author(s):

T Sugii ◽

T Okumura

Keyword(s):

Hydraulic Conductivity ◽

In Situ Test ◽

Unsaturated Hydraulic Conductivity

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In Situ Determination of Parameters of Hydrogen Isotopes Interaction with Materials Using Dynamic Sorption Method

Fusion Science & Technology ◽

10.1080/15361055.2020.1712006 ◽

2020 ◽

Vol 76 (3) ◽

pp. 333-340 ◽

Cited By ~ 1

Author(s):

T. V. Kulsartov ◽

Zh. A. Zaurbekova ◽

I. E. Kenzhina ◽

M. T. Gabdullin ◽

Yu. V. Ponkratov ◽

...

Keyword(s):

Hydrogen Isotopes ◽

Dynamic Sorption ◽

Sorption Method ◽

Determination Of Parameters

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GMT - A Large Scale In-Situ Test of the Gas Migration Properties of Engineered Barriers

MRS Proceedings ◽

10.1557/proc-663-553 ◽

2000 ◽

Vol 663 ◽

Author(s):

S. Vomvoris ◽

P. Marschal ◽

W. Kickmaier ◽

K. Ando ◽

M. Fukaya ◽

...

Keyword(s):

Radioactive Waste ◽

Large Scale ◽

Swiss Alps ◽

Gas Migration ◽

Laboratory Studies ◽

In Situ Test ◽

Rock Laboratory ◽

Engineered Barriers ◽

Future Plans

ABSTRACTThe GMT experiment (Figure 1) was initiated in the summer of 1997 under the auspices of RWMC (Radioactive Waste Management Center, Japan). It is part of the experiments conducted within Phase V (1997-2002) of Nagra's Underground Rock Laboratory at Grimsel, in the Swiss Alps [1]. The currents status and results from the site characterization activities and laboratory studies are presented. Future plans are also outlined.

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STUDIES IN CYSTIC FIBROSIS: DETERMINATION OF SWEAT ELECTROLYTES IN SITU WITH DIRECT READING ELECTRODES

PEDIATRICS ◽

10.1542/peds.43.5.794 ◽

1969 ◽

Vol 43 (5) ◽

pp. 794-798

Author(s):

Louis Kopito ◽

Harry Shwachman

Keyword(s):

Cystic Fibrosis ◽

Large Scale ◽

Skin Surface ◽

Sweat Glands ◽

Direct Reading ◽

Screening Programs ◽

Cystic Fibrosis Screening ◽

Pilocarpine Iontophoresis

An evaluation is made of newly developed specific-ion electrodes for determining sodium and chloride on the skin surface following the stimulation of the sweat glands by pilocarpine iontophoresis. This procedure offers a rapid (5 to 6 minutes), convenient, and safe means for large-scale cystic fibrosis screening programs for screening infants and children. Caution is urged in the evaluation of the reading since a failure to sweat may result in a misleading value.

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Determination of drugs in plasma by high-performance thin-layer chromatography.

Clinical Chemistry ◽

10.1093/clinchem/24.8.1386 ◽

1978 ◽

Vol 24 (8) ◽

pp. 1386-1392 ◽

Cited By ~ 10

Author(s):

D C Fenimore ◽

C M Davis ◽

C J Meyer

Keyword(s):

Thin Layer ◽

Thin Layer Chromatography ◽

High Performance ◽

Large Scale ◽

Ultraviolet Spectrophotometry ◽

Reflectance Spectrometry ◽

Ultraviolet Reflectance ◽

Layer Chromatography

Abstract High-performance thin-layer chromatography was used to determine chlorpromazine, amitriptyline, nortriptyline, imipramine, desipramine, phenobarbital, and phenytoin in plasma, to demonstrate the utility of this technique for routine analysis. We quantitated the separated components by use of ultraviolet reflectance spectrometry with detection limits as low as 1 microgram/liter. Regressions of psychoactive agents extracted from plasma were linear over the range of 0 to 300 microgram/liter. The anti-convulsant drugs, phenobarbital and phenytoin, were determined over a range of 0 to 50 mg/liter. Analyses were rapid, reproducible, and well-suited to large-scale programs. Separated components also can be identified in situ by ultraviolet spectrophotometry.

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