COMPARISON OF EXPERIMENTAL ARCHING PHENOMENA RESULTS OF SANDY SOIL WITH LIMIT EQUILIBRIUM METHOD

9th International Multidisciplinary Scientific GeoConference - SGEM2009, www.sgem.org, SGEM2009 Conference Proceedings/ ISBN 10: 954-91818-1-2, June 14-19, 2009, Vol. 1, 187-196 pp

ABSTRACT

The ratio of observed vertical stress to its theoretical value in a soil mass which has
settlement potential could be defined as arching ratio. This phenomenon could be
observed in some projects, such as earth-fill dams, tunnels, and piles. Arching in earthfill
dams may results in hydraulic fracture due to increase of pore water pressure, is the
most important result of arching. Hydraulic fracture causes internal cracking of clay
core which in turn results in more water seepage.

To evaluate the arching effect, an apparatus has been designed and manufactured which
is called Arching Force Measurement Apparatus (AFMA).Several tests have been
carried out to assess this phenomenon in a sandy-soil and to study the effective
parameters on the problem such as relative density, height of soil sample in
experimental soil container, and vertical overburden pressure. Finally, arching factor
has been defined and calculated, and comparison has been made with limit equilibrium
method.

Keywords: Arching, sandy soil, Arch Force Measurement Apparatus, (AFMA), Limit equilibrium.