Post Construction and Long Term Settlement of an Embankment Dam Computed with Two Constitutive Models

A. H. Bhutto, S. Zardari, G. S. Bhurgri, M. A. Zardari, R. Bhanbhro, B. A. Memon

Abstract


For the settlement computation of an embankment dam, the soil stiffness is of great importance. Unfortunately, due to the lack of funds allocated for geotechnical investigation, stiffness parameters are commonly not evaluated as compared to strength properties. As a result, this may create hindrance in the use of advanced constitutive models such as Hardening Soil Model (HSM). In this study, the settlement with respect to depth and long term settlement of an embankment dam computed with Mohr-Coulomb Model (MCM) is compared with that of HSM applied to foundation soil only with limited data on stiffness. The results show that the MCM overestimated settlement in comparison with HSM. The settlement increment of MCM, in comparison with HSM, at the crest and at the depth of 120m was 53% and 82% respectively after the filling of the reservoir. The settlement computed with MCM and HSM were 2.9% and 1.35% of the dam height. It can be interpreted that the settlement predicted with MCM is unrealistically high due to the single constant value of modulus of elasticity (MOE), while the predictions of HSM are in agreement with the literature. In addition, the long term settlement computed using MCM is about 59% higher than that of HSM for the condition after the filling of the reservoir. This paper shows that the settlement of an embankment dam could be predicted reliably by using HSM even when a limited number of stiffness data is available.


Keywords


long term settlement; embankment dam; settlement with respect to depth; stiffness; crest

Full Text:

PDF

References


V. Gikas, M. Sakellariou, “Settlement analysis of the Mornos earth dam”, (Greece): Evidence from numerical modeling and geodetic monitoring”, Engineering Structures, Vol. 30, No. 11, pp. 3074-3081, 2008

R. Y. Liang, B. O. Nusier, A. H. Malkawi, “A reliability based approach for evaluating the slope stability of embankment dams”, Engineering Geology, Vol. 54, No. 3-4, pp. 271-285, 1999

A. D. Penman, “Instrumentation monitoring and surveillance”, in: Embankment Dams, Routledge, 2018

R. M. Roosta, A. Alizadeh, ”Simulation of collapse settlement in rock fill material due to saturation”, International Journal of Civil Engineering, Vol. 10, No. 2, pp. 93-99, 2012

R. Mahinroosta, A. Alizadeh, B. Gatmiri, “Simulation of collapse settlement of first filling in a high rockfill dam”, Engineering Geology, Vol. 187, pp. 32-44, 2015

T. Schanz, P. A. Vermeer, P. G. Bonnier, “The hardening soil model: formulation and verification”, in: Beyond 2000 in Computational Geotechnics, pp. 281-296, CRC Press, 1999

Y. Hejazi, D. Dias, R. Kastner, “Impact of constitutive models on the numerical analysis of underground constructions”, Acta Geotechnica, Vol. 3, No. 4, pp. 251-258, 2008

R. B. Brinkgreve, “Selection of soil models and parameters for geotechnical engineering application”, Geo-Frontiers Congress 2005, Austin, USA, January 24-26, 2005

R. F. Obrzud, “On the use of the Hardening Soil Small Strain model in geotechnical practice”, Numerics in Geotechnics and Structures, pp. 15-32, Elmepress International, 2010

R. B. J. Brinkgreve, S. Kumarswamy, W. M. Swolfs, Plaxis Reference Manual, PLAXIS, 2017

N. Janbu, “Soil compressibility as determined by oedometer and triaxial tests”, Proceedings of the European Conference on Soil Mechanics and Foundation Engineering (ECSMFE), Vol. 1, pp. 19-25, 1963

P. V. Soos, “Properties of Soil and Rock”, in: Grundbau Taschenbuch Part 4, Ernst & Sohn, 1990 (in German)

A. H. Bhutto, S. Zardari, M. A. Zardari, G. S. Bhurgri, B. A. Memon, R. Bhanbhro, M. M. Babar, “Mohr-Coulomb and Hardening Soil Model Comparison of the Settlement of an Embankment Dam”, Engineering, Technology & Applied Science Research, Vol. 9, No. 5, pp. 4654-4658, 2019

G. Hunter, R. Fell, The Deformation Behaviour of Embankment Dams, The University of New South Wales, 2003

A. Araei, “Artificial neural networks for modeling drained monotonic behavior of rockfill materials”, International Journal of Geomechanics, Vol. 14, No. 3, Article ID 04014005, 2013

ASCE Task Committee on Instrumentation and Dam Performance, Guidelines for Instrumentation and Measurements for Monitoring Dam Performance, ASCE, 2000




eISSN: 1792-8036     pISSN: 2241-4487