The Main Content of Membrane Structure Design Analysis

The membrane structure has a unique architectural style, strong artistry, a strong modern atmosphere, good mechanical properties, and excellent optical thermal performance

The design analysis of the membrane structure mainly includes three aspects: shape determination, load analysis and cutting analysis.

1. Determining the shape of membrane architecture

(1) The problem of determining the shape of a given prestress distribution: presuppose the distribution of stress in the membrane structure, and then analyze and calculate according to the reasonable force or economic principles to obtain the initial geometric state of the membrane.

(2) The problem of determining the shape of a given geometric boundary condition: determine the geometric boundary conditions of the membrane structure in advance, and then calculate and analyze the prestress distribution and spatial shape.

Commonly used computer form-finding methods are: force density method, dynamic relaxation method, and finite element method.

2. Load analysis of membrane structure

The load analysis of the membrane structure is carried out on the basis of the appearance and initial stress distribution obtained from the shape analysis to check whether the strength and stiffness of the structure meet the predetermined requirements under the load combination.The nonlinear finite element method is basically adopted in the load analysis of the membrane structure, which divides the structure into discrete elements and nodes. The elements and elements are connected through the nodes, and the external load is applied on the nodes. The solution is obtained by establishing the equilibrium equation of the nodes.

The characteristics of light, soft and floating membrane structure determine the content of wind resistance calculation of membrane structure has its own characteristics.

(1) Determination of static wind pressure coefficient

The shape coefficient of wind load is an important parameter to describe the uneven characteristics of wind pressure on the structure.However, due to the different shapes of membrane structures, the wind compression coefficient cannot be obtained directly from the load specification.Therefore, wind tunnel tests are basically required for larger membrane structures to obtain the correct local wind pressure net pressure coefficient and average wind carrier shape coefficient. Because the wind tunnel test needs to meet a series of similarity criteria, such as geometric similarity, Reynolds number similarity, etc., it is usually impossible to satisfy these similar conditions, so the wind tunnel simulation results sometimes exceed the measured values by a large amount.

Membrane Architecture

(2) determination of pulsating wind pressure coefficient

Membrane constructionhas a large displacement under load, and the change of configuration will affect the wind field around it. Therefore, the wind dynamic response process of membrane structure is a fluid-solid coupling process. The wind tunnel test of this dynamic process must adopt aeroelastic model, so it is difficult to realize. In recent years, more and more attention has been paid to the development of "numerical wind tunnel". Simply put, it combines computational fluid mechanics and computational structural mechanics, USES computational fluid mechanics to simulate the wind field around the structure, USES computational structural mechanics to simulate the membrane structure, and realizes the coupling effect between the two by means of the transmission of some parameters. However, this method is still in the experimental stage.