Civil Engineering Reference
In-Depth Information
frame. The lateral earth pressure developed behind the shear wall structure (Fig
7.25) is more than 25% larger than its counterpart found behind the rigid frame.
7.3 Conclusions
The parametric numerical analysis of rigidly framed earth retaining structures
(RFERS) with varying lateral stiffness, bay lengths, number of bays, number of
stories simulating the addition of the backfill soil with varying properties using
staged construction computation indicates that the magnitude of lateral earth
pressure developed behind the rigid frames varies with the magnitude of the lateral
stiffness of the frames.
In general, it was found that for rigid frames with relatively lower stiffness, the
magnitude and distribution of the lateral earth pressure developed behind the
frames at the end of the backfill stage is comparable to the lateral earth pressure
obtained from the Coulomb's active earth pressure theory, and is also in line with
the soil loads stipulated by some of the national building codes adopted in the
United States, such as the International Building Code and the BOCA code. The
soil loads prescribed by ASCE 7-98 were found to slightly overestimate the
pressure developed behind the more flexible frames.
On the other hand, for the stiffer frames, the lateral earth pressure was found to
be reasonably comparable to Coulomb's active earth pressure for the top half of
the retained soil height, and increasing linearly thereafter to reach the magnitude
of the lateral earth pressure at rest at the bottom of the retained height.
This conclusion may not be extended however to encompass framed structures
braced against lateral sway such as shear wall or braced frame structures where
the lateral earth pressure was found to be even larger than that for rigid frames.
