Lightweight structures are characterized by having a rather small mass relative to the applied load, which include tensile (or tension) structures, frame supported structures , air supported structures , air inflated structures, cable network structures, tensegrities (cable-and-strut) , geodesic domes and grid shells.
For lightweight structures, the structural forms (shapes) need to be determined through a tedious optimization process.
To view the structure definitions and images of lightweight structures, please visit the website of Lightweight Structures Association.
How was I involved in lightweight & tensile structures?
I was involved in the research for lightweight & tensile structures from the late 1980s to early 1990s, when I worked for Hohai University. At beginning, I joined Prof. Qian Ruojun’s research group to develop a program for analyzing space truss. Then, I got a chance to join a research project, “Research on the Strength, Stability and Limit Performance of New Type Space Structures”, which was sponsored by National Natural Science Foundation of China, from 1991 to 1994. Four state key universities cooperated for this project. They are, namely, Zhejiang University, Tongji University, Southeast University and Hohai University. My role was to study the structural behavior of tensile membrane structures, method for form-finding and load state analysis. I developed the theory and analysis model, and coded the program for analysis of membrane structures by finite element method. However, due to the lack of enough information at that time, the work was very difficult.
After that, I was involved in a few research projects related to lightweight structures. When I was studying at The National University of Singapore, I had a chance to read more books and look up on research papers about lightweight & tensile structures. At that time, there were a growing number of lightweight & tensile structure projects being built. Later, even as my main work became the analysis and design for high-rise building structures when I worked as a Civil & Structural Engineer for DE Consultants(s) Pte Ltd, my interest was still kept in tensile structures.
In 2003, I joined my current employer – Right Tech(s) Pte Ltd, a specialist company in membrane structures. Ever since I have joined the company, an in-house design department has been set up. My career in designing and building tensile structures started since then.
What is the purpose of this website?
I set up the TensileWorld website, hoping to provide a platform to others who also have an interest in lightweight & tensile structures. This website would be a platform for them to share ideas & exchange experiences each other.
This website can also serve as a window for those who want to know more about lightweight and tensile structures in China.
Any comments and/or suggestions on this website are welcome. Please feel free to drop me an email.
Design Process for Tensile Structures
For light-weight & tensile structures, the design process differs greatly from those for traditional building structures. Let's take tensile membrane structures for example. There are two essential features differ from conventional structures, i.e. membrane structures need form-finding and cutting pattern generation. The design of a membrane structure is a complex procedure consisting of many parts which results in an iterative process. This process may include: conceptual design; physical modelling; computer modelling; form-finding; analysis; and cutting pattern generation.
Form-Finding
Generally the form-finding is to provide the exact shape of structure. The design usually commences with a sketch drawn by the architect. This sketch provides the basis for further conceptual design. Because the membrane is flexible, the surface shape and structural stability is mainly governed by the stresses, either physical modelling or computer simulation of the structure is required to help the designer to find realistic shapes.
Load State Analysis
Due to the large deflections to which membrane structure is inherently subjected, geometrically non-linear analysis need to be performed. Additionally, given the large amount of data required to model membrane structures, the graphical representation of the deformation, force and stress results must be able to be easily controlled to highlight the relevant data.
Cutting Pattern Generation
Cutting pattern generation includes the determination of the distortion- and stress-free lengths of all cable and membrane pieces as a prerequisite for the cutting of cable or membrane materials and their knotting and sewing together to form a structure. In the cutting pattern generation real material values are used. Moreover this step becomes important because the slack lengths determine the prestress in the structure when the structure is analysed & checked under different loading conditions.
More detailed information & some beautiful pictures
If you are interested in reading more on lightweight & tensile structures, such as material properties of fabric/membrane (including structural, thermal, visual, acoustics and fire properties for Teflon/PVC/ETFE/Tenara materials), design theory and engineering practices, engineering detailing, fabric patterning, fabrication and installation, or want to see some more project pictures, or would like to talk with me and others on tensile structures, please click here to join our Forum.
TensileWorld.com © Xu Chuanxi. All Rights Reserved.
No part of this website may be used elsewhere without written permission from the webmaster.
Design v4 © Xu Jia Kun.