Imperial College London
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Dr Adam Jan Sadowski

Faculty of Engineering, Department of Civil and Environmental Engineering

Senior Lecturer
 
 
 
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Contact

 

+44 (0)20 7594 3065a.sadowski Website

 
 
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Location

 

318Skempton BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Liu:2019:10.1061/(ASCE)EM.1943-7889.0001571,
author = {Liu, Q and Sadowski, AJ and Rotter, JM},
doi = {10.1061/(ASCE)EM.1943-7889.0001571},
journal = {Journal of Engineering Mechanics - ASCE},
title = {Ovalization restraint in four-point bending tests of tubes},
url = {http://dx.doi.org/10.1061/(ASCE)EM.1943-7889.0001571},
volume = {145},
year = {2019}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Four-point bending tests have been a staple in many structural engineering experiments as a reliable  way  of  assessing  the  bending  resistance  of  circular  hollow  sections,  tubes  and cylindrical  shells,  and  they  continue  to  be  widely performed.  However,  relatively  little attention appears to have been paid to quantify the effects of different boundary conditions on the test outcome. In particular, the restraint or freedom given to the cross-section at the ends  of  the  specimen  to  ovalize  can  have  a  significant  impact  when  the  specimen  is  in  an appropriate length range. Ovalization is an elastic  geometrically nonlinear phenomenon that is  known  to  reduce  the  elastic  bending  resistance  by  as  much  as  half  in  long  tubes  or cylinders. This  paper  presents  a  short  distillation  of  some  recent  advances  in  understanding  the buckling of cylindrical shells under uniform bending, identifying the strong influence of the cylinder  length  on  cross-section  ovalization.  A  sample  set  of  three-dimensional  load application  arrangements  used  in  existing  four-point  bending  tests  was  simulated  using finite   elements,   allowing   an   assessment   of   the   differences   caused   by   pre-buckling ovalization  and  its  effect  on  the  tested  bending  resistance.  The  study  is  limited  to  elastic behaviour  to  identify  the  effect  of  ovalization  alone  in  reducing  the  stiffness  without material  nonlinearity.  The  outcomes  demonstrate  that  maintaining  circularity  at  the  inner load  application  points  by  appropriate  stiffening  has  a  significant  effect.  With  freedom  to ovalize,  a  significant  reduction  in  stiffness  occurs,  leading  to  much  lower  bending resistance at buckling than may be achievable in practical applications.
AU  - Liu,Q
AU  - Sadowski,AJ
AU  - Rotter,JM
DO  - 10.1061/(ASCE)EM.1943-7889.0001571
PY  - 2019///
SN  - 0733-9399
TI  - Ovalization restraint in four-point bending tests of tubes
T2  - Journal of Engineering Mechanics - ASCE
UR  - http://dx.doi.org/10.1061/(ASCE)EM.1943-7889.0001571
UR  - http://hdl.handle.net/10044/1/63809
VL  - 145
ER  -
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