Pre cast concrete tanks
The key design elements of the galglass
post-tensioned pre cast concrete tank system are
as follows:
Design and manufacture of the pre cast concrete
tank wall units complies with the general provisions
of BS8110 and BS8007, and the nominal design life
in normal operation can therefore be taken as 60
years.
The major stresses encountered during the life of
units are handling stresses induced during
offloading and erection, and the units are therefore
designed to withstand such stresses without
permanent damage, in accordance with the
requirements of BS8110 Cl.5.1.3.
As standard, galglass pre cast concrete
post-tensioned tank wall units have internal
unbonded tendons.
Tendons are typically 15.2mm dia. multi-strand, grease-impregnated cables with 1.5mm
thick plastic sheathing, all in accordance with BS5896. For further enhanced corrosion
protection, each tendon is installed with a sacrificial zinc anode which will corrode in
preference to the tendon in the extremely unlikely event that all the other protective s
ystems fail at once. The zinc anode is sized to provide a nominal tendon protection
period of 100 years.
This provides corrosion protection for external tendons in exposed environments
equivalent to that specified in BS8007 Cl.4.3, and is a system, which has been
extensively used in pre cast concrete tank construction in similar environmental
conditions throughout mainland Europe for many years.