Testing, simulation and design of high strength steel tubular elements
File(s)
Author(s)
Meng, Xin
Type
Thesis
Abstract
High strength steel tubular elements combine the merits of both high strength steel and tubular profiles and are being increasingly used in the construction industry. However, more widespread use is inhibited by current structural design provisions, which are limited in scope and hindered in their development by a scarcity of experimental and numerical data. The primary aim of this study is therefore to expand the test and numerical data pool for high strength steel tubular elements and to develop more efficient yet safe structural design rules for use in practice.
Four standard tubular profiles – circular, elliptical, square and rectangular hollow sections, are considered in this study. An experimental investigation into the cross-sectional behaviour of hot-rolled and cold-formed high strength steel hollow sections was conducted, including eleven stub column tests, twelve beam tests and 45 short beam-column tests; 3D laser-scanning and digital image correlation were employed in these experiments. Finite element (FE) models were established to replicate the test results and to generate supplementary numerical data. Shortcomings in the existing codified design rules were highlighted through comparisons of design predictions with the obtained test and FE data, and suitable amendments to the Eurocode 3 (EC3) design provisions were proposed accordingly.
The member buckling behaviour of high strength tubular elements was subsequently examined through an experimental study, which consisted of 24 column buckling tests and twenty long beam-column tests, and a parallel numerical simulation programme. Modified EC3 design rules, featuring a yield strength-dependent imperfection factor and re-calibrated buckling and interaction curves, were developed and shown to yield greatly improved design predictions over the current approaches in terms of accuracy and consistency.
In addition to the improvements within the EC3 design framework, a novel approach incorporating the generalised slenderness and reference resistances was proposed for the structural design of steel tubular sections to further enhance the ease of use and design efficiency. The benefits were clearly shown through comparisons of predicted resistances with the available test and FE results.
Four standard tubular profiles – circular, elliptical, square and rectangular hollow sections, are considered in this study. An experimental investigation into the cross-sectional behaviour of hot-rolled and cold-formed high strength steel hollow sections was conducted, including eleven stub column tests, twelve beam tests and 45 short beam-column tests; 3D laser-scanning and digital image correlation were employed in these experiments. Finite element (FE) models were established to replicate the test results and to generate supplementary numerical data. Shortcomings in the existing codified design rules were highlighted through comparisons of design predictions with the obtained test and FE data, and suitable amendments to the Eurocode 3 (EC3) design provisions were proposed accordingly.
The member buckling behaviour of high strength tubular elements was subsequently examined through an experimental study, which consisted of 24 column buckling tests and twenty long beam-column tests, and a parallel numerical simulation programme. Modified EC3 design rules, featuring a yield strength-dependent imperfection factor and re-calibrated buckling and interaction curves, were developed and shown to yield greatly improved design predictions over the current approaches in terms of accuracy and consistency.
In addition to the improvements within the EC3 design framework, a novel approach incorporating the generalised slenderness and reference resistances was proposed for the structural design of steel tubular sections to further enhance the ease of use and design efficiency. The benefits were clearly shown through comparisons of predicted resistances with the available test and FE results.
Version
Open Access
Date Issued
2020-05
Date Awarded
2020-11
Copyright Statement
Creative Commons Attribution NonCommercial No Derivatives Licence
Advisor
Gardner, Leroy
Sponsor
European Commission. Community Research and Development Information Service
Grant Number
RFCS-2015-709892
Publisher Department
Civil and Environmental Engineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)