Eversafe Marine Moves 4000 tonnes building 100 meters
admin:admin time:2013-10-29
With Eversafe Marine airbags, one 4000 tonnes building, the 26 m high concrete sculpture with 22 m diameter circle base was moved 100 meters to make way for the expansion of a national road by Eversafe Marine. It is the first time in the world to relocate building with marine airbags.
Moving caissons or vessel’s sections with airbags is not rare, those objects all have strong structural strength and low gravity center that ensure the movement safety. Regarding structure relocation, the most used method is steel bar plus concrete girder which needs to do lots of concrete wok and being time consuming. Using airbags to move building is a new try for both owners and Eversafe Marine.
The project feasibility research was performed by Hebei Academy of Building Research, from structure reinforcement plan to relocation procedure , the entire process was proved to be positive. Then Eversafe Marine took the job.
That building was originally located in the traffic circle of one national road. Due to expansion of road, it needed to be moved north 100 meters to its new location. The move path is natural ground with 1.1/100 slope in lengthways and 2 cm level error in width.
In order to lift the sculpture with airbags, people need to place support girder beneath the structure base first. To dig tunnels in 1 m thick lime earth under the structure base was the first difficulty for the team. It took one month to place seven girders and get rid of all earth.
Before airbag lifting, the pulling and holding system were set up to control the structure. One 25 T winch was deployed to pull and 10 Tonnes heavy was attached to act as brake.
Eight airbags were inserted between the 50 cm high girders. At about 0.2 MPa pressure the building was lifted up from the support girders. People removed the blocks and cleaned the pathway for the coming movement.
The first 50 cm move of huge sculpture went smoothly with the winch pulling. When pull stops the brake force from attached 10 T heavy holds the structure tightly. Eversafe team adjusted some airbags’ pressures to keep structure balance. Repeating pull and stop, the building moved from original flat spot to the built ramp gradually.
At that time some problems happened. The eccentric centre of sculpture and ramp level error made it difficult to get building balance. Thus the movement of building deflected. And due to different roughness of building base and the ramp, airbags began to contort in varying degrees. Eversafe team had to adjust every contorted airbags after every stop and took some technical methods to drive building move back to the right way.
After 20 days hard work the sculpture arrived at its final location. People inserted concrete girders between airbags then deflated airbags slowly to let the building sit on the hard support. Then the permanent concrete base was casted for the sculpture.
This very hard project is a rigorous trial for both airbag and Eversafe team. All bags had been heavily compressed for several days, not mention the concrete circle base abraded bags everyday. Eversafe team also withstanded huge pressures from the technical difficulties and practical limitations. Anyway it is a successful try of applying airbag heavy move technology in building field. Comparing with general building relocation method, it saved more than 70% cost and much time. Another advantage of using airbags to move structure is no harm to the environment which is invaluable.
