Membrane structure concept design |
From the structural methods can be roughly divided into skeleton type, tension type, inflatable membrane structure in three forms. 1. Frame Supported Structure 2. Tension Suspension Structure 3. Inflatable membrane structure (Pneumatic Structure) The basic elements of a tensioned membrane structure are usually: membranes, cables, and support structures (stems, arches, or other rigid members). Membranes A new type of building material that has been recognized as the "sixth building material" after brick, stone, concrete, steel and wood. The membrane material itself cannot be pressed or bent, so it is necessary to introduce a proper pretension for the membrane structure to work properly. In addition, another important condition to ensure the normal operation of the membrane structure is to form reciprocal surfaces. In order to reduce the deformation of the structure, the traditional structure must increase the resistance of the structure; while the membrane structure disperses the load by changing the shape, so that the minimum internal force increases. When the membrane structure is deformed near the equilibrium position, two kinds of restoring force can be generated: one is caused by the geometric deformation; the other is caused by the material strain. Generally, the geometric stiffness is much larger than the elastic stiffness. Therefore, for each diaphragm to have good stiffness, a negative Gaussian surface should be formed as far as possible, ie, “high point” and “low point” are formed along the diagonal direction. The "high point" is usually provided by a mast, and perhaps for this reason, some literature also refers to the tensile membrane structure as a suspension membrane. As the elastic boundary of the membrane material, the membrane is divided into a series of diaphragms, thereby reducing the free supporting length of the membrane and making the surface of the membrane easier to form a large curvature. According to the literature, the free support length of the membrane should not exceed 15 meters, and the coverage area of the monolithic membrane should not exceed 500 square meters. In addition, another important role of the cable is to provide additional support for the support structure such as the mast, so as to ensure that the support structure does not collapse due to the damage of the membrane material. |