It is a judgment call by the engineer to determine the level of pre-stress (预张力).
Usually his judgment is based on 2 criteria, deformation & constructability.
If the deformation of the membrane/cable will result in ponding of water or snow, damage of fabric because of abrasion, distortion of clamping plates because of large geometry change or fluttering of fabric under the wind and may be other issues. The pre-stress level should be increased to mitigate these problems.
In fabrication the fabric is compensated according to the pre-stress level which can be between 1% and 6% depends on the material. This compensated membrane panel will require you to pull the edge a distance to its clamping position, this may increase the difficulty of installation. It is an issue with cost, time and safety. You may want to lower the pre-stress level if the jacking distance is too long.
I recommend 3.5 KN/m pre-stress as a starting point for your project. 作者:
hhux 时间: 2003-1-9 06:45 标题: 回复： 张拉薄膜结构中膜的常用合理预张力范围是多少
