Building with earth - Gernot MINKE (1)

Domes
In order to construct a structurally optimised
dome without formwork, the BRL developed
a rotational guide that is fixed to a
vertical mast. An angle is fixed at the end of
the rotating arm, against which the mason
lays the adobe or soil block, allowing block
to be positioned with precision. Illustrations
15.33 to 15.36 show the application of this
construction technique for an earthquakeresistant
dome with an 8.8 m free span that
is 5.5 m in height, built in La Paz, Bolivia, in
2000. The dome is stabilised by two reinforced
concrete ring beams, one at the bottom
of the dome, another at the top of the
foundation. In order to provide good sound
distribution within the dome, the adobes
were made by hand in a special mould with
rounded edges. The acoustic behaviour of
the dome was further refined by deepening
the vertical joints in order to achieve some
sound absorption and by a slight cantilevering
position, which prevents the sound from
being focused towards the centre of the
dome.
15.34 15.33
15.33 to 15.34 Rotational
guide
15.35 to 15.36 Finished
dome
15.37 Wrongly designed
plinth with eccentric
thrust line, which collapses
easily when hit by
seismic shocks
15.38 Earthquakeresistant
design for a lowcost
housing project in
Gujarat, India
15.39 to 15.40 Dangerous
shapes of vaults,
Bam, Iran
15.41 Vault which withstood
earthquake at Bam,
Iran, Dec. 2003
15.35
15.36
144
Earthquake-resistant building