摘要(英) |
A constitutive model
for silty sand named “SHASOVOD” combined FLAC3D software was used to
study the anchorage behavior of tied-back anchors in silty sand. A field
test program was conducted to verify the applicability of the numerical
program; the parametric studies were then carried out by numerical
analyses. It was found that the numerical results are in a good
agreement with those by field tests. The friction force dominates the
anchorage capacity of a shaft tension anchor. Whether the yielding zone
of an anchor develops to ground surface and structural wall or not
depending on the overburden depth H and the embedded depth Z, this study
have been suggested the minimum overburden depth Hmin and minimum
embedded depth Zmin herein. It can be found, as the relative density of
soil or the fixed length of an anchor increased, the yielding zone also
expanded. When the embedded depth, the overburden depth or the fixed
length of an anchor increased, the anchorage capacity also increased.
Increasing fixed length should be a better method to increase the
anchorage capacity; ultimate load per unit fixed length was about
55kN/m. However, when the fixed length of an anchor is greater 30 m, the
incremental of anchorage capacity per unit fixed length was decreased
due to progressive yield of friction stress along fixed end. According
to the numerical results, when the inclination angle, overburden depth,
embedded depth, or fixed length increased, the coefficient of lateral
earth pressure Kf decreased. The coefficient Kf always less than the
coefficient of passive earth pressure Kp; however, it was greater than
the coefficient of earth pressure at rest K0. |