Folding of membrane structure refers to the out of plane or out of curved deformation of membrane material under the condition of unidirectional tensile stress. Generally, it can be divided into two types: one is caused by the relaxation of membrane material due to the disappearance of tension on the membrane surface in one direction, which is called structural folding; The other is caused by defects in the production process of membrane materials, improper heat sealing or improper packaging folding, which is called material folding.

1、 Structural fold

The influence of wrinkles on membrane structure and structure performance cannot be ignored, which is not only reflected in the visual effect. The appearance of wrinkles will lead to the redistribution of membrane surface pretension, so that the stress in some areas of the membrane surface is lower than the design value, while the stress in other areas is higher than the design value. When the membrane surface stress is higher than the design value, it will lead to greater strain and mutation of the membrane material, and even local tearing of the membrane material. In addition, wrinkles will also affect the beauty and drainage performance of the structure. Therefore, during the construction of membrane structures, wrinkles of membrane materials under the long-term load combination of normal use should be avoided as far as possible.

2、 Material fold

There are few material folds, which are permanent and cannot be treated. In actual production, membrane structure processing and membrane structure installation are the main reasons that affect the membrane surface wrinkles of membrane structures. Constructors should pay more attention to these two aspects and strengthen specific measures to reduce the membrane surface wrinkles of membrane structures, so as to realize the beauty of membrane structures.