Project COSA

European Commission Directorate-General For The Information Society And Media Directorate-General For Research And Innovation

Description

Comparison of geomechanical computer codes for salt - Addendum to COSA I Report
Nuclear energy and safety
Energy research

Informations

• Publié par: EUROPEAN-COMMISSION-DIRECTORATE-GENERAL-FOR-THE-INFORMATION-SOCIETY-AND-MEDIA-DI
• Nombre de lectures: 12
• Langue: English
• Poids de l'ouvrage: 3 Mo

Extrait

Commission of the European Communities
Project COSA:
Comparison of geomechanical
computer codes for salt
Addendum to COSA I Report Commission of the European Communities
;a
Project COSA:
Comparison of geomechanical
computer codes for salt
Addendum to COSA I Report
D. Piper,1 M. J. S. Lowe,1 G. Vouille2
' W. S. Atkins Engineering Sciences
Woodcote Grove, Ashley Road
Epsom, Surrey KT18 5BW, United Kingdom
2 École des mines
Centre de mécanique des roches
35, rue Saint Honoré
F-77305 Fontainebleau
Contract No FI1W/0054/UK
Final report
Work performed under the European Communities' research programme
'Management and storage of radioactive waste'
Part A, Task 4: Geological disposal studies
Directorate-General
Science, Research and Development
1989 EUR 12134 EN Published by the
COMMISSION OF THE EUROPEAN COMMUNITIES
Directorate-General
Telecommunications, Information Industries and Innovation
L - 2920 Luxembourg
LEGAL NOTICE
Neither the Commission of the European Communities nor any person acting
on behalf of then is responsible for the use which might be made of
the following information
Cataloguing data can be found at the end of this publication
Luxembourg: Office for Official Publications of the European Communities, 1989
ISBN 92-825-9947-7 Catalogue number: CD-NA-12134-EN-C
© ECSC-EEC-EAEC, Brussels · Luxembourg, 1989
Printed in Belgium TABLE OF CONTENTS
Page
1. INTRODUCTION 1
2. EMP - CREEP TESTS (G-VOUILLE) 3
3. RWTH - VARIANT SOLUTIONS 17
4. FORAKY - FLORA RESULTS 31
5. ENRESA/ETSIM - MINIMEF AND ADINA RESULTS 4
6. LGC - PLACRE RESULTS 6 5
7. REFERENCES 7 3
8. ACKNOWLEDGEMENTS 5 1. INTRODUCTION
The first phase of the COSA project (COSA I) covering the period
1984-86 was reported in Reference 1. Since its publication a
number of additional items relating to COSA I have become
available. They are presented herein. They are not intended to be
completely self-explanatory and the document as a whole should be
read in association with Reference 1.
The additional items fall into three categories:
(i) Details of the creep tests conducted by EMP for their
variant solution of the second benchmark (as summarised in
section 7.1.1 of Reference 1).
(ii) Further presentation of the variant solutions submitted
by RWTH and included in sections 7.1.3 and 7.2.2 of
Reference 1.
(iii) Solutions of the first and second benchmarks by 'new' codes
(and/or participants) which were introduced to the COSA
project after publication of Reference 1.
This addendum was originally issued in April 1987 and has been
raised to issue 02 with the incorporation of the ENRESA/ETSIM and
LGC solutions in sections 5 and 6. 2. EMP - CREEP TESTS
Two triaxial creep tests were performed by EMP on Asse rock salt
cored from the same blocks as those used by TH Delft in its heating
experiments, one of which formed the experimental basis for the
second benchmark. The tests are described in the following pages
which are a copy of the relevant EMP report.
The report shows that a form of the Lemaitre law accurately
reproduces the experimental behaviour. EMP subsequently carried
out calculations of the second benchmark problem using this law and
the results are given in chapter 7 of the final report. CREEP TESTS ON ASSE ROCK SALT
I- INTRODUCTION
Within the framework of the COSA project, it has
been decided to carry out two creep tests on ASSE Rock Salt
cored from the same blocks as those used by DELFT University
in its heating experiments. In the following report, the
results of these tests are given and a comparison is done
between the various rhéological models which are proposed to
represent the behavior of this salt.
II- DESCRIPTION OF THE CREEP TESTS
These tests are carried out under triaxial stress
conditions : the confining pressure is kept constant with a
value of 15 HPa and the axial pressure is fixed to 19 MPa
during a week; at the end of this week,it is increased up to
23 MPa an kept constant during a new week, then to
27 MPa and 31 MPa with the same time schedule.
During the test the axial strain is monitored and
then, plotted versus time.
Two tests are performed in the same way,with the
only difference that for one test the temperature is 40' C
while it is QO°C for the other.
The realization of the whole program could not be
done, due to various problems which took place during the
last week of test : on one hand,leaks of oil occured on
circuit which delivered the axial pressure and it was neces­
sary to readjust this pressure frequently, on the other
hand, the current was cut off several times and thus, the
temperature could not be kept constant during this week.