Fall
2002
Importance
of Settlement During Foundation Design
Md. Anwarul Hoque
The overall safety of the
foundation depends on the following two factors q
It must be safe against shear failure, and q
It must not exceed tolerable settlement.. It is observed that most of the
company give their recommendation on the basis of shear failure, but they
don’t consider or take cautionary steps regarding settlement failure of the
foundation. Foundation settlement under
loads can be classified into three types, q
Immediate settlement (Si) q
Consolidation settlement (Sc) q
Secondary consolidation settlement (Ss) In this study the Ss
is assumed zero. Because the secondary settlement is not significant for
inorganic clays and silly soils. Thus, Total Settlement= Immediate (Si)
+ Consolidation (Sc) An intensive study is carried
out on 2 (two) renowned company on their suggested are report. It is observed
that the settlement of the individual column footings foundation are greater
then the allowable values and thus may cause damage to the structure in future.
But as immediate settlement is much less than the allowable value there is less
chance of immediate affect. For Raft Foundation, settlement of the raft
foundation is within the range of the allowable values, thus casing no future
damage. As it is observed in our
study that settlement has a significant affect on the stability of foundation in
the future so during foundation design sufficient safety measure should be taken
regarding settlement failure of the foundation. |