CONSTRUCTION AND OPTIMIZATION OF THE ANTI-VIBRATION MEGA-FRAME PLATFORMS

摘要

A new 16-leg mega-frame platform (MFP) was constructed based on an actual jacket platform (W12-1) using the mega-frame theory. Two control platforms, traditional jacket platform and jacket platform with upright column, were also built based on principle that all the platforms had the equal or similar weight, the same upper deck structure and the same function. Every column of the MFP had the most equal load and the smallest stress under the same horizontal and vertical unequal loads. So the MFP had the best loads bearing ability of all the three types' platforms above. In order to find out the effect of the structure parameters' change to the platforms' static performance, many types of MFPs were constructed by changing the number, the height and the stiffness of the major beams and/or by changing the stiffness and the angle of the major columns on the basic model MFP-313707. The analyses of all types of MFPs with different parameters under the same horizontal and vertical unequal loads show that: 1) The increase of the major beams' height makes the platforms' columns bear more equally than the increase of the major beams' number; 2) The increase of major columns' stiffness has better effect on the platform's maximal deformation decrease and the columns' loads equality. And the effect of the increase of the major beams' and columns' stiffness on the MFP's static capability has the optimal values. Beyond the optimal values, the increase of the platforms' weight caused by the increase of the stiffness is much bigger than the decrease of the platform's deformation and the increase of the columns' loads' equality. The analyses also show that the slope angle of the platforms' columns must be set around 10°.