DEVELOPMENT OF MEASUREMENT EQUIPMENT OF MEMBRANE STRESS FOR MEMBRANE STRUCTURES USING WHITE NOISE SOUND WAVE-Improvement of Measurement Equipment, Verification Experiment and Practical Measurement of Actual Suspension Membrane Structure-

One of the most important issues in keeping membrane structures in stable condition is to maintain the proper stress distribution over the membrane. However, it is difficult to determine the quantitative real stress level in the membrane after the completion of the structure. The stress relaxation phenomenon of the membrane and the fluttering effect due to strong wind or ponding caused by precipitation may cause severe damage to the membrane structure itself. Therefore, it is very important to know the magnitude of the existing stress in membrane structures for their maintenance. The authors have proposed a new method for separately estimating the membrane stress in two different directions using sound waves instead of directly measuring the membrane stress. The new method utilizes the resonance phenomenon of the membrane, which is induced by sound excitations given through an audio speaker. During such experiment, the effect of the surrounding air on the vibrating membrane cannot be overlooked in order to assure high measurement precision. In this paper, an evaluation scheme for the added mass of membrane with the effect of air on the vibrating membrane and the correction of measurement error is discussed. In addition, three types of membrane materials are used in the experiment in order to verify the expandability and accuracy of the membrane measurement equipment.

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Computer-Integrated Manufacturing System for Membrane Structures

MATEC Web of Conferences ◽

10.1051/matecconf/201925802025 ◽

2019 ◽

Vol 258 ◽

pp. 02025

Author(s):

Kazuo Yokobori ◽

Tomo Miura

Keyword(s):

Membrane Structure ◽

Three Dimensional ◽

Numerical Data ◽

3D Models ◽

Space Structure ◽

Computer Integrated Manufacturing ◽

Support Vector ◽

Membrane Structures ◽

Structure Estimation ◽

Steel Panels

A membrane structure is a space structure composed of a membrane material (fabric or film), cables, and steel frames, among others. It reduces the environmental load for transporting materials and constructions; for instance, compared with conventional roofs that have steel panels or tiles, the membrane structure of a roof is lightweight. Computer analysis and three-dimensional (3D) models are required for determining the stable shape of such tensile structures. It is useful to use computer-integrated systems for the design and manufacturing process because these 3D models consist of numerical data. In this study, we developed a system program based on artificial intelligence methods, with a support vector machine instead of human judgment for the membrane structure estimation and for a probabilistic optimization to predict the differences caused by production loss etc. and compare the results after actual production. And we got close predicted results to the person.

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Analysis of Wind-Induced Vibration of a Spoke-Wise Cable–Membrane Structure

Journal of Marine Science and Engineering ◽

10.3390/jmse8080603 ◽

2020 ◽

Vol 8 (8) ◽

pp. 603

Author(s):

Hua Huang ◽

Yaoqiang Xian ◽

Wei Zhang ◽

Mengxue Guo ◽

Kun Yang ◽

...

Keyword(s):

Stress Relaxation ◽

Dynamic Behavior ◽

Damage Assessment ◽

Membrane Structure ◽

Aerospace Industry ◽

Time History ◽

Wind Load ◽

Membrane Structures ◽

Wind Resistance ◽

Wind Induced Vibration

Lightweight cable–membrane structures can span large distances and undertake aesthetically pleasing shapes. They are widely used for roofs and modern structural canopies and in the aerospace industry for large on-board antenna reflectors that are to be deployed in space. This paper studies a wind-induced vibration under different cable stress relaxation conditions based on the wind load time-history to obtain the dynamic behavior of such a structure. Particularly, the focus is put upon its wind resistance in the event of stress relaxation. This research can provide an important reference for the design of wind resistance, damage assessment, and emergency maintenance for the spoke-wise cable–membrane structure (SCMS).

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Membrane structures - an introduction and manual for the design process of membrane structures

10.32920/ryerson.14666409 ◽

2021 ◽

Author(s):

Niclas Hörth

Keyword(s):

Finite Element ◽

Design Process ◽

Membrane Structure ◽

Architectural Design ◽

Modern Society ◽

Design Element ◽

Membrane Structures ◽

Linear Behavior ◽

Numerical Finite Element

Membrane structures are are an unfrequently used architectural design element in the modern society due to their simplicity and elegance. However, these structures require often in their design process the usage of complicated numerical finite element softwares because of their non-linear behavior. Written calculations can only be used for the preliminary determination of the required pretensioning, but not for the whole design process, which includes several different loading cases. Therefore, this work with the title Membrane Structures - An Introduction and Manual for the Design-Process of Membrane Structures intends to develop a possible way of determining stresses in a membrane structure caused by additional loadings.

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Boundary shape design of planar membrane structures based on an airy stress model

Advances in Mechanical Engineering ◽

10.1177/1687814020916039 ◽

2020 ◽

Vol 12 (4) ◽

pp. 168781402091603

Author(s):

Mingjun Liu

Keyword(s):

Stress Field ◽

Membrane Structure ◽

Shape Design ◽

Stress Model ◽

Membrane Structures ◽

Principal Stresses ◽

Accurate Analysis ◽

Simple Method ◽

Edge Structure ◽

Stress Simulation

Maintaining surface accuracy is crucial to realizing the required performance of membrane structure. However, compressive stress inevitably leads to wrinkling, and the accurate analysis of the stresses becomes significant. The present study analyzed membrane structures with discrete loads. First, a simple method was proposed and the stress field was accurately described using an Airy stress model. The first and second principal stresses were obtained, and regions of wrinkling with negative stress were predicted. Second, for a square membrane structure, vertical tensions around the boundary were applied such that in-plane stresses were more evenly distributed. Finally, to reduce the wrinkling areas more effectively, an arc-edge structure was designed by removing some areas of low-stress. Simulation results showed that the in-plane stress field distribution was described accurately and the wrinkling regions were diminished effectively with the proposed method.

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Hailstone-induced dynamic responses of pretensioned umbrella membrane structure

Advances in Structural Engineering ◽

10.1177/1369433220940149 ◽

2020 ◽

Vol 24 (1) ◽

pp. 3-16 ◽

Cited By ~ 5

Author(s):

Changjiang Liu ◽

Fan Wang ◽

Xiaowei Deng ◽

Song Pang ◽

Jian Liu ◽

...

Keyword(s):

Dynamic Response ◽

Membrane Structure ◽

Impact Analysis ◽

Impact Load ◽

Dynamic Responses ◽

Flexible Structure ◽

Membrane Material ◽

Membrane Structures ◽

Characteristic Points ◽

The Impact

The membrane structure is a flexible structure, which is easy to vibrate or even relax under dynamic load. Engineering accident analysis shows that the relaxation of membrane structure is more likely to lead to structural failure. In this article, the impact load problem is combined with the flexible structure to analyze the impact of hailstone impact load on the dynamic response of membrane structure. First, the umbrella membrane stretching device was designed and manufactured, and the hailstone impact test was carried out on the umbrella membrane structure with polyvinyl chloride membrane material. Dynamic response data, tension relaxation of side cables and vibration deformation of umbrella membrane structures impacted by hailstones with different sizes and different characteristic points were obtained. In the numerical analysis, the form-finding analysis of umbrella membrane structure is carried out by finite element method, and the transient impact analysis is conducted in LS-DYNA. Finally, the reliability of the research results is verified by comparing the numerical and experimental results. The general laws and conclusions are drawn and the disaster-causing mechanism of membrane structure impacted by hailstone is revealed. On the whole, although the probability of hailstone destroying the membrane material directly is very small, it will relax the membrane structure and affect the safety of membrane structure. The conclusions of this article provide a theoretical basis for the design and maintenance of membrane structures.

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Tensioned Membrane Structures in the Form of Egg Shape

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.989 ◽

2013 ◽

Vol 405-408 ◽

pp. 989-992 ◽

Cited By ~ 9

Author(s):

Mohd Syazwan Mohd Noor ◽

Hooi Min Yee ◽

Abdul Hamid Haslinda ◽

Ong Chong Yong

Keyword(s):

Computer Program ◽

Stress Analysis ◽

Membrane Structure ◽

Membrane Surface ◽

Surface Shape ◽

Displacement Method ◽

Membrane Structures ◽

Long Span ◽

Egg Shape

Tensioned membrane structures are pre-stressed membrane structures that are appropriate to be used for long span application. Tensioned membrane structures must depend on their shape and internal pre-stress alone to achieve stability and to carry the loads. Some of the largest stadiums, airports, convention halls and commercial places are tensioned membrane structures. It is essential to perform shape-finding analysis while dealing with tensioned membrane structures. In this study, shape-finding analysis is carried out using computer program for stress analysis which is based on theory of nonlinear displacement method. Shape-finding of membrane surface bordered by Egg has been investigated. In this study, the possibility of adopting the form of Egg as surface shape for tensioned membrane structure has been studied.

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