COMPUTATIONAL METHODS IN ENGINEERING AND SCIENCE
EPMESC X, Aug. 21-23, 2006, Sanya, Hainan, China
©2006 Tsinghua University Press & Springer
Numerical Simulations of the Behavior of Foundations on
Reinforced Soil
C. M. Tou, T. M. H. Lok *
Department of Civil and Environmental Engineering, University of Macau, Macau SAR, China
Email: [email protected], [email protected]
Abstract
Since after the discovery of the improvement of the ultimate bearing capacity of foundations with
geosynthetics such as geotextiles, geogrid, etc., a lot of experimental studies have been carried out to
investigate the optimium configurations of the geosynthetics. In this study, finite element plain strain
numerical model was created to investigate several parameters that would probably affect the behavior of
reinforced foundations. The model used Duncan Hyperbolic model to simulate the foundation soil. Failure
was defined when the settlement of the foundation reached δ = 0.30B. The parametric studies of the
single-layer soil system include the depth to the first reinforcement layer, the length of the reinforcement, the
number of reinforcement layers, spacing between the reinforcement, tensile strength of the reinforcement
and types of soils such as cohesive and cohesionless soil. Based on the numerial simulation, it is shown that
the optimum depth to the first reinforcement layer is at about 0.15B and the result implies that the
reinforcement does not need to be anchored in any way prior to placing the fill, as was previously thought
essential to achieve a completely reinforced soil system. Also, the increase in bearing capacity in
cohesionless soil is much higher than in cohesive soil due to the different mechanisms of interaction between
the reinforcement and the soil.
B
d
u
h
h
h
h
1
2
3
N-1
N
Cohesionless
OR
Cohesive soil
Geosynthetic
reinforcement
layer
Figure: A FE plain strain model with reinforcement for single-layer soil
system & optimum depth to the first reinforcement layer
REFERENCES
1. Kotake N, Tatsuoka F, Tanaka T, Siddiquee MSA, Huang CC. FEM simulation of bearing capacity of
level reinforced sand ground subjected to footing laod. Geosynthetics International, 8(6): 501-549.
2. Shin EC, Das BM. Experimental study of bearing capacity of a strip foundation on geogrid-reinforced
sand. Geosynthetics International, 7(1): 59-71.
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