2787
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
THREE-DIMENSIONAL MODELS OF BEARING CAPACITY – CASE STUDY
Models tridimensionnels de capacité de portant- Etude de cas.
Carlos Petrônio Leite da Silva, DSc.
Federal Institute of Brazilia, Brazilia, Brazil,
Newton Moreira de Souza, DSc.
University of Brasília, Brazilia, Brazil,
Carlos Medeiros Silva, DSc.
Embre- Brazilian Engineering and Foundations, Brazilia, Brazil,
ABSTRACT: To mitigate risk in geotechnical constructions by making borings and pile load tests that enable the elaboration of bi
and three-dimensional models, which assure the correct analysis and evaluation of the associated risks to design and to the
construction execution should be one of the targets of a Geotechnical Engineering. Generally, the analyses done in terms of design
level are conducted under some uncertainties, especially concerning geological-geotechnical formation which has a great influence on
the soil-foundation system, however, it has been looking for techniques that assure a good evaluation of such constructions, by the
elaboration and usage of three-dimensional models, based on data from geotechnical and geological survey. The organization,
treatment and specialization of soil data furnish models that help in the decision and mitigating process of risks involved in those
constructions. The obtained results by the usage of the referred methodology show that data interpolation during the three-
dimensional modeling process decrease uncertainties that come from the natural variability of the soil.
RÉSUMÉ : Pour atténuer les risques dans les constructions géotechniques en faisant des essais de chargement sur pieux et des tests de
forages qui permettent l'élaboration de modèles bi et tridimensionnels, qui assurent la bonne analyse et la bonne évaluation des risques
associés à la conception et à l'exécution de la construction devraient être l'un des objectifs de
l’
ingénierie géotechnique. En général,
les analyses effectuées en terme de niveau de conception sont menés malgré certaines incertitudes, notamment en ce qui concerne la
formation géologique-géotechnique qui a une grande influence sur le système sol-fondation, cependant, on a effectué des recherches
de techniques qui assurent une bonne évaluation de ces constructions, par l'élaboration et l'utilisation des modèles en trois dimensions,
à partir des données de l'enquête géotechnique et géologique. L'organisation, le traitement et la spécialisation des données du sol
fournissent des modèles qui aident dans le processus de décision et d'atténuation des risques liés à ces constructions. Les résultats
obtenus par l'utilisation de cette méthode montrent que l'interpolation des données pendant le processus de modélisation
tridimensionnelles diminue les incertitudes qui proviennent de la variabilité naturelle du sol.
KEYWORDS: bearing capacity, three-dimensional model, geotechnical risk.
MOTS CLES : capacité de portant, model tridimentionnel, risque géotechnique.
1 INTRODUCTION
The estimation of the bearing capacity, the definition of the
resistant surface, the tip elevation of the bases and the execution
control of the foundations are in many times defined under
uncertain conditions which are caused by nature and by the
intrinsic characteristics of the soil and by the deficiencies and
limitations of the preliminary studies which are the support for
the elaboration of a design.
The ideal would be that the foundation could offer a
minimum risk concerning the safety and the maximum economy
about the costs. The satisfy such dual idea it is necessary to
have wide range and consistent preliminary studies for the
understanding of the geological-geotechnical behavior of the
soil and its interaction with the foundation and the
superstructure Silva (2011).
To handle such problem, the elaboration and the usage of
three-dimensional models, based on data from geotechnical,
geological and geo-physical surveys start to gain a space in civil
engineering constructions, especially in foundation and
excavation constructions. Based on such philosophy, firstly the
design forces (loads) were defined; secondly, the sub-surface
model (resistant surface) (soil layers) that would be used in the
foundation solution was set.
It is known that to solve the referred problem there are
many dimensioning methods which result in many possible
foundation solutions. However not even the best method , that
is, the one that best adapts itself to the local soil and to the
construction’s expectations can skip from the natural variability
of the soil. Therefore, to understand such variability is the great
task of the geotechnical engineering, which is the key point of
this article, which proposes a way, for not saying a new one, but
efficient to organize, treat and specify in a bi or tridimensional
way the soil data, to furnish information that help in the
decision making process and in the mitigation of the risks which
take part in the foundation constructions.
To validate and measure the quality of the three-
dimensional methods, results from load testes were used which
decreased in a good way the uncertainties concerning the real
execution condition and the foundations’ behaviors, in terms of
bearing capacity and deformability.
At the end, the obtained results from the three-dimensioning
spacialization are shown throughout the proposed methodology.
The results obtained from the application of the methodology
show that on the contrary of the traditional methods, the data
interpolation during the three-dimensional modeling process
reduced the uncertainties of the natural variability of the soil.
Three-Dimensional Models of Bearing Capacity – Case Study
Modèles tridimensionnels de capacité de portante – Étude de cas.
Leite da Silva C.P.
Federal Institute of Brazilia, Brazilia, Brazilr
Mor ira de Souza N.
University of Brasília, Brazilia, Brazil
M deiros Silva C.
Embre- Brazilian Engineer ng and Fo
, Brazil
