Building with earth - Gernot MINKE (1)

A simple solution for stabilising rammed
earth walls of lesser thicknesses is to use
L, T, U, X, Y or Z shaped elements (15.17).
Due to their angles, they have better stability
against lateral forces. If a wall is 30 cm
thick, the free ends of the elements should
not be longer than 3 /4 and no shorter than
1/3 of their heights (see 15.19). This minimal
length is necessary to transfer loads diagonally
to the plinth or foundation. If the free
ends are longer than 3 /4 of their heights,
they should be stabilised by another angle.
If the angle is well fixed on the bottom to
the plinth and on the top to a ring beam,
it should be larger or higher. Nevertheless,
height should not exceed the width by
eight times (see 15.6).
The forces perpendicular to the wall are
transferred into the angle parallel to the
direction of force. This means that it is transferred,
instead of creating a concentration
of stress at the inner corner of the angle.
It is advisable, therefore, to enlarge the
section at this corner, as shown in 15.17
and 15.18.
15.17
15.18
15.16
15.16 Simple test to
study the influence of
wall shape on resistance
to seismic shocks (BRL)
15.17 Elements with
correct corner details
15.18 Corner solution
15.19 Recommended
proportions
15.19
I < 0.75h > 0.33h
h
h
33 cm
I < 0.75h > 0.33h
normal solution
optimised solution
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Earthquake-resistant building