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本帖最后由 猴子魔君 于 2015-7-18 09:26 编辑
Continuous slip formed gravity base structure supports under construction in a Norwegian fiord. The tower cranes delivered concrete to the support cylinders during the continuous pour of concrete to create seamless walls.
The Troll A platform has an overall height of 472 metres (1,549 ft), weighs 683,600 tons (1,2 million tons with ballast)[2] and has the distinction of being the tallest structure ever moved by mankind. The platform stands on the sea floor 303 metres (994 feet) below the surface of the sea and one of the continuous-slip-formed[3] concrete cylindrical legs (the leg containing the import and export risers) has an elevator that takes over nine minutes to travel[3] from the platform above the waves to the sea floor. The walls of Troll A's legs are over 1 metre thick made of steel reinforced concrete formed in one continuous pour (slip forming)[3] and each is a mathematically joined composite of several conical cylinders that flares out smoothly to greater diameters at both the top and bottom, so each support is somewhat wasp-waisted viewed in profile and circular in any cross-section (see picture at right). The concrete legs must be able to withstand intense pressure so are built using a continuous flow of concrete, a lengthy process that takes 20 minutes per 5 cm laid.
The four legs are joined by a "chord shortener", a reinforced concrete box interconnecting the legs, but which has the designed function of damping out unwanted potentially destructive wave-leg resonances by retuning the leg natural frequencies.[3] (Not present in the picture at right.) Each leg is also sub-divided along its length into compartments a third of the way from each end which act as independent water-tight compartments.[3] The legs use groups of six 40 metres (130 ft) tall[3] vacuum-anchors holding it fixed in the mud of the sea floor. |
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狗仔卡
发表于 2015-4-18 17:20:46
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这是什么啊！！！！