Actes du colloque - Volume 2 - page 804

1686
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
8 CONCLUSIONS
We calculate static and dynamic displacements, accelerations
and stresses over 50 year period.
Regarding displacements, our results show that these will be
admissible and should not promote damages and difficulties on
the section of Metro Line 12 studied here.
Shear and normal stresses will increase in the future at
section of the tunnel supported by the thicker clay strata or at
section where the direction of the tunnel changes. The structure
design of these stations must account for these changes bearing
in mind that estimated stress increments in the future can be far
from negligible.
Figure 7. Evolution of the displacementover time.
7.2.1
Evolution of normal stress
Normal stresses at the connection of the tunnel with the Zapata
Station increase around 30 to 40% over the 2042-2062. These
increases occur at elbow zones; especially those on soft deposits
of greater thickness (see Fig. 8).
9 REFERENCES
ICG 2009.
FLAC3D V4.0: Fast Lagrangian Analysis of Continua in 3
Dimensions
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NTC 2004. Normas Técnicas Complementarias para el Reglamento de
Construcciones del Distrito Federal.
Gaceta Oficial del Distrito
Federal.
Tome II, 55-78.
Ovando E. and Romo M. P. 1991. Estimación de la velocidad de ondas
S en la arcilla de la ciudad de México con ensayes de cono”.
Sismodinámica
2, 107-123.
Ovando E, Ossa A and Romo M.P. 2007. The sinking of Mexico City:
Its effects on soil properties and seismic response.
Soil Dynamics
and Earthquake Engineering
, Vol. 27, 333-343.
Figure 8. Evolution of the normal stresses over time. Case of Y
direction.
Ovando E, Ossa A. 2004 Modelo elastoviscoplático para la
consolidación de los suelos y su aplicación al hundimiento regional
de la ciudad de México. In: Memorias, XXII Reunión Nacional de
Mecánica de Suelos. México, Guadalajara, Vol. 1, 291–299.
Santoyo E., Lin R. and Ovand, E. 1989. El cono en la exploración
geotécnica.
TGC Geotecnia
. México.
7.2.2
Evolution of shear stress
The shear stresses increase around 30 to 60% for the 2042-2062
period of analysis, only in the connections supported on thicker
soft material, as are elbow 2 and Tunnel- Parque de los Venados
station zone. Shear stresses remain constant with time at other
connections upon the occurrence of seismic events (see Fig. 9).
Yin J. H., Graham J. 1996. Elastic visco-plastic modelling of one
dimensional consolidation.
Geotechnique
46 (3,5). 15-527
Figure 9. Evolution of the shear stresses over time. Case of XY shear
stress.
1...,794,795,796,797,798,799,800,801,802,803 805,806,807,808,809,810,811,812,813,814,...913