Prediction of the bearing capacity and behavior of monitored soft soil embankment foundations
Authors:
A. Aissi, University of Annaba, Annaba, Algeria
S. Bensehamdi, Dr. Sci. (Tech.), National School of Mining and Metallurgy, Head of Mining Engineering Department, Annaba, Algeria
Abstract:
Purpose. This research aims to identify and analyse the bearing capacity and subsidence of a monitored embankment clay foundation through the data exploitation of the in situ monitoring results (settlement plates). The results are then compared to the theoretical calculations used the pressure-meter test toward evaluating its reliability. Thus, the present research highlights the importance of understanding the method of bearing capacity evaluation as well as the recent orientation towards numerical simulation by finite element method using software PLAXIS 8.2 to evaluate the stability and to perform a more realistic analysis of the soft soil foundation behaviour beneath embankments.
Methodology. The analysis is based on the in situ monitored by the settlement plates with different depths to understand the real behaviour of the foundation under loading, and the exploitation of the geotechnical investigation by pressure-meter test. The loading programme and numerical modelling via finite element method was also used.
Findings. Major experimental results and findings were related to the role of the in situ monitored used in this analysis and the conformity of the results between the different techniques for the bearing capacity evaluation. In addition, the loading program of the embankmentand the curve of loading with settlement have shown to affect the best understanding of the bearing capacity analyses.
Originality. This variety of techniques helps us to understand the foundation behaviours under loading. The ability of the pressure-meter tests and the numerical modelling via finite element method to identify the bearing capacity in these conditions was evaluated, and can be generalized to the remaining zones that are closer and that share the same geotechnical characteristics. To better understand the feasibility and the reliability of each technique of the bearing capacity evaluation, the results were confronted to the real behaviour (instrumentation) through the exploitation of the loading programme data.
Practical value. The instrumentation results can be useful as a database for the behaviours models validation, as well as theoretical technique for the bearing capacity evaluation. The results of monitoring obtained can also be generalized to the other zones that share the same geotechnical characteristics. The importance of the loading programs effectsthe staged construction technique presented in the results of the analysis can also be exploited.
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