Details
| Originalsprache | Englisch |
|---|---|
| Publikationsstatus | Veröffentlicht - 2020 |
| Veranstaltung | 54th U.S. Rock Mechanics/Geomechanics Symposium - Virtual, Online Dauer: 28 Juni 2020 → 1 Juli 2020 |
Konferenz
| Konferenz | 54th U.S. Rock Mechanics/Geomechanics Symposium |
|---|---|
| Ort | Virtual, Online |
| Zeitraum | 28 Juni 2020 → 1 Juli 2020 |
Abstract
The time-dependent system behavior plays an important role in tunnel construction with shotcrete. In addition to the sequential tunneling with a cross-sectional subdivision, the material behavior of the young shotcrete has a special significance. Young shotcrete, freshly applied to the rock mass has a low strength, which develops higher values by increasing time. In addition, young shotcrete is creepable up to an age of about 10 days, which means, the deformations resulting from the tunneling can be absorbed by the shotcrete lining by the time-dependent material behavior. In contrast to building construction in civil engineering, the temporal development of the young's modulus plays an important role in shotcrete construction, as a substantial part of the tunnel lining load during tunneling already occurs at a time when the building material has not yet reached its full stiffness. Once the shotcrete lining has reached an age of about 10 days, it is assumed that with an occurring increase in deformation, an additional stress is set, which can be described sufficiently accurately by the stress-strain behavior of a hardened concrete described in standards. At the Institute of Geotechnical Engineering of the Leibniz University Hannover, a material law for shotcrete has been developed with which the time-dependent strength and deformation behavior (transient creep) can be described. This constitutive law Lubby2-SB is used in three-dimensional numerical simulations to evaluate the stress and strain states in the vicinity of a tunnel structure. Just as in conventional building construction and after a certain built-in quantity of building material, the material parameters are verified with regard to their suitability, the stress-strain behavior of the concrete must be determined individually for each building on site from time to time. This control is particularly important for the young shotcrete, since the tunnel lining has a supporting function even at an early construction stage. The paper presents the formulation of the time-dependent material law for shotcrete and its application for a three-dimensional numerical tunnel model. For this purpose, tunneling with the finite difference program Flac3D is simulated.
ASJC Scopus Sachgebiete
- Erdkunde und Planetologie (insg.)
- Geochemie und Petrologie
- Erdkunde und Planetologie (insg.)
- Geophysik
- Erdkunde und Planetologie (insg.)
- Geotechnik und Ingenieurgeologie
Zitieren
- Standard
- Harvard
- Apa
- Vancouver
- BibTex
- RIS
2020. Beitrag in 54th U.S. Rock Mechanics/Geomechanics Symposium, Virtual, Online.
Publikation: Konferenzbeitrag › Paper › Forschung › Peer-Review
}
TY - CONF
T1 - Application of a time-dependent material law for shotcrete to a three-dimensional tunnel model
AU - Zapf, Dirk
AU - Leuger, Bastian
N1 - Publisher Copyright: © 2020 ARMA, American Rock Mechanics Association Copyright: Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020
Y1 - 2020
N2 - The time-dependent system behavior plays an important role in tunnel construction with shotcrete. In addition to the sequential tunneling with a cross-sectional subdivision, the material behavior of the young shotcrete has a special significance. Young shotcrete, freshly applied to the rock mass has a low strength, which develops higher values by increasing time. In addition, young shotcrete is creepable up to an age of about 10 days, which means, the deformations resulting from the tunneling can be absorbed by the shotcrete lining by the time-dependent material behavior. In contrast to building construction in civil engineering, the temporal development of the young's modulus plays an important role in shotcrete construction, as a substantial part of the tunnel lining load during tunneling already occurs at a time when the building material has not yet reached its full stiffness. Once the shotcrete lining has reached an age of about 10 days, it is assumed that with an occurring increase in deformation, an additional stress is set, which can be described sufficiently accurately by the stress-strain behavior of a hardened concrete described in standards. At the Institute of Geotechnical Engineering of the Leibniz University Hannover, a material law for shotcrete has been developed with which the time-dependent strength and deformation behavior (transient creep) can be described. This constitutive law Lubby2-SB is used in three-dimensional numerical simulations to evaluate the stress and strain states in the vicinity of a tunnel structure. Just as in conventional building construction and after a certain built-in quantity of building material, the material parameters are verified with regard to their suitability, the stress-strain behavior of the concrete must be determined individually for each building on site from time to time. This control is particularly important for the young shotcrete, since the tunnel lining has a supporting function even at an early construction stage. The paper presents the formulation of the time-dependent material law for shotcrete and its application for a three-dimensional numerical tunnel model. For this purpose, tunneling with the finite difference program Flac3D is simulated.
AB - The time-dependent system behavior plays an important role in tunnel construction with shotcrete. In addition to the sequential tunneling with a cross-sectional subdivision, the material behavior of the young shotcrete has a special significance. Young shotcrete, freshly applied to the rock mass has a low strength, which develops higher values by increasing time. In addition, young shotcrete is creepable up to an age of about 10 days, which means, the deformations resulting from the tunneling can be absorbed by the shotcrete lining by the time-dependent material behavior. In contrast to building construction in civil engineering, the temporal development of the young's modulus plays an important role in shotcrete construction, as a substantial part of the tunnel lining load during tunneling already occurs at a time when the building material has not yet reached its full stiffness. Once the shotcrete lining has reached an age of about 10 days, it is assumed that with an occurring increase in deformation, an additional stress is set, which can be described sufficiently accurately by the stress-strain behavior of a hardened concrete described in standards. At the Institute of Geotechnical Engineering of the Leibniz University Hannover, a material law for shotcrete has been developed with which the time-dependent strength and deformation behavior (transient creep) can be described. This constitutive law Lubby2-SB is used in three-dimensional numerical simulations to evaluate the stress and strain states in the vicinity of a tunnel structure. Just as in conventional building construction and after a certain built-in quantity of building material, the material parameters are verified with regard to their suitability, the stress-strain behavior of the concrete must be determined individually for each building on site from time to time. This control is particularly important for the young shotcrete, since the tunnel lining has a supporting function even at an early construction stage. The paper presents the formulation of the time-dependent material law for shotcrete and its application for a three-dimensional numerical tunnel model. For this purpose, tunneling with the finite difference program Flac3D is simulated.
UR - http://www.scopus.com/inward/record.url?scp=85097964274&partnerID=8YFLogxK
M3 - Paper
T2 - 54th U.S. Rock Mechanics/Geomechanics Symposium
Y2 - 28 June 2020 through 1 July 2020
ER -