Peri technology for LNG liquid gas tanks in Cameron, USAadmin
In the US state of Louisiana, three enormous liquid gas tanks are currently being built at the same time using Peri know-how. Each of the structures has an 80 m diameter and, after completion, a wall height of 44 m. In the bottom third, the wall cross-section tapers externally from 90 cm at the base to 75 cm. The reinforced concrete wall then runs vertically up to the top with a constant thickness of 75 cm on both sides. Four buttresses, each 1.70 m thick and 4.50 m long, have been integrated into the ring wall to act as vertical bracing elements.
Engineers from the Fort Worth office of formwork and scaffolding manufacturer, Peri, provided the contractors with a cost-effective climbing formwork solution using the Vario GT 24 girder wall formwork system together with CB climbing scaffold. With a permissible fresh concrete pressure of 45 kN/mÂ², only two DW 20 tie points are required with a concreting height of 4.65 m. However, numerous steel installation elements in the shear walls have had to be taken into consideration when determining the tie positions.
Together with the type-tested CB climbing scaffold system, the formwork and climbing scaffold can be moved in only one crane lift from cycle to cycle. With the Peri solution, the contractors are in the position is to climb the circular-shaped containers in two-week cycles. For each container, 80 climbing units are in use. The tanks will be fully operational in 2008. Two additional containers are already being planned.
LNG stands for liquefied natural gas that has been processed to remove either valuable components e.g. helium, or those impurities that could cause difficulty downstream, e.g. water. The volume of the natural gas can be reduced through liquefaction to approximately two parts per thousand of the original state. Thus storage and transportation over long distances where pipelines do not exist is much more cost-efficient.