2D Finite Element Method on the Scaling Law for Strip …onlinepresent.org/proceedings/vol120_2015/137.pdf2D Finite Element Method on the Scaling Law for Strip Footing Myungjae Lee
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2D Finite Element Method on the Scaling
Law for Strip Footing
Myungjae Lee1 and Heejung Youn1
1 Department of Civil Engineering, Hongik University, Sangsu-dong, Mapo-gu, Seoul,
Republic of Korea.
Abstract. This paper investigates the similitude law for strip footing resting on
cohesionless soils using a 2D finite element analyses. The 2D finite element
analyses were conducted considering three different conditions: laboratory
model test under 1-g, centrifuge test under n-g, and full scale test under 1-g.
The scaling relations in stress and displacement among the tests were examined
for varying internal friction angle. The friction angles used were 32, 35, 38,
41 and 44°. The cohesionless soils were simulated using the Hardening Soil
model, which enables the increase in shear strength and stiffness with depth.
Based on series of numerical results, the scaling relations were suggested for
bearing pressure and settlement of strip footing
Keywords: friction angle, strip footing, similitude law, scaling relation, unit
bearing capacity, 2D finite element
1 Introduction
It is possible to easily predict the bearing capacity of shallow foundation in sandy soil
through an indoor experiment. However, the bearing capacity as to the foundation in
sandy soil is largely affected by confining pressure. Moreover, an indoor experiment
can hardly simulate an increase in confining pressure in relation to depth. On that
account, it is hard to make an accurate prediction in regard to the full scale. To solve
the aforementioned problem, Ko (1988) presented the scaling relation of each of the
following tests in Table 1: full scale test, centrifuge test and laboratory model test. Ko
(1988) leveraged geometric scale ratio as n and stress scale ratio as N.
This paper calculated the scaling relations between the 1g laboratory model test,
centrifuge test and full scale test by means of the 2D finite element program called
‘PLAXIS’. Moreover, this paper analyzed which impact this scaling relations would
create with the changes in friction angle, elastic coefficient and fitting parameter ‘m’.
This paper leveraged gravitational acceleration of 1g (9.81 m/s2) and 20-g (196.2
m/s2).
1 Heejung Youn, Assistant Professor, School of Urban and Civil Engineering, Hongik