Author : Shu Yan
Publisher : Open Dissertation Press
ISBN 13 : 9781361289976
Total Pages : pages
Book Rating : 4.2/5 (899 download)
Book Synopsis Bolted and Screwed Connections of Thin Sheet Steels at Elevated Temperatures by : Shu Yan
Download or read book Bolted and Screwed Connections of Thin Sheet Steels at Elevated Temperatures written by Shu Yan and published by Open Dissertation Press. This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Bolted and Screwed Connections of Thin Sheet Steels at Elevated Temperatures" by Shu, Yan, 閆澍, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: The structural behaviour of single shear bolted connections, double shear bolted connections and single shear screwed connections of thin sheet steels at elevated temperatures has been investigated in this study. The current design rules on bolted and screwed connections of thin sheet steels for cold-formed steel structures are applicable for ambient temperature condition only. These design rules may not be applicable for elevated temperature conditions. Therefore, design guidelines should be prepared for bolted and screwed connections of cold-formed steel structures at elevated temperatures. A total of 30 tensile coupon tests were conducted to investigate the material deterioration of the thin sheet steels at elevated temperatures, and also to determine the critical temperatures for connection tests. A total of 510 tests on single shear bolted connections, double shear bolted connections and single shear screwed connections of thin sheet steels at elevated temperatures was performed in the temperature ranged from 22 to 900?C using both steady state and transient state test methods. The test results were compared with the predicted values calculated from the North American, Australian/New Zealand and European specifications for coldformed steel structures. In calculating the nominal strengths of the connections, the reduced material properties of the thin sheet steels were used due to the deterioration of material at elevated temperatures. It is shown that the design strengths predicted by these specifications are generally conservative at elevated temperatures. Finite element models for single shear bolted connections, double shear bolted connections and single shear screwed connections were developed and verified against the experimental results. Explicit dynamic analysis technique was used in the numerical analyses. Extensive parametric studies that included 490 finite element specimens were carried out using the verified finite element models to evaluate the bearing strengths of bolted connections as well as the tilting and bearing strengths of screwed connections of thin sheet steels at elevated temperatures. Design equations for bearing strengths of bolted connections as well as design equations for tilting and bearing strengths of screwed connections were proposed based on both the experimental and the numerical results in the temperature ranged from 22 to 900?C. The bearing strengths of bolted connections as well as the tilting and bearing strengths of screwed connections obtained from the test specimens and the finite element analyses were compared with the predicted strengths calculated using the proposed design equations and also compared with the design strengths calculated using the current North American, Australian/New Zealand and European specifications with consideration of the reduced material properties at elevated temperatures. It is shown that the proposed design equations are generally more accurate and reliable in predicting the bearing strengths of bolted connections as well as the tilting and bearing strengths of screwed connections of thin sheet steels at elevated temperatures than the current design
