A Hybrid Particle Swarm Optimization and Genetic Algorithm for Model Updating of A Pier-Type Structure Using Experimenta

  • PDF / 1,873,662 Bytes
  • 11 Pages / 595 x 842 pts (A4) Page_size
  • 116 Downloads / 211 Views

DOWNLOAD

REPORT


rticle Swarm Optimization and Genetic Algorithm for Model Updating of A Pier-Type Structure Using Experimental Modal Analysis Alireza MOJTAHEDIa, *, Shahriar BAYBORDIb, Amin FATHIb, Aliakbar YAGHUBZADEHb a Department of Water Resources Engineering, Faculty of Civil Engineering, University of Tabriz, Tabriz 51666-

16471, Iran b Department of Maritime Engineering, Amirkabir University of Technology, Tehran, Iran

Received March 5, 2020; revised June 16, 2020; accepted July 20, 2020 ©2020 Chinese Ocean Engineering Society and Springer-Verlag GmbH Germany, part of Springer Nature Abstract Conventional  design  of  pier  structures  is  based  on  the  assumption  of  fully  rigid  joints.  In  practice,  the  real connections  are  semi-rigid  that  cause  changes  in  dynamic  characteristics.  In  this  study,  quality  of  the  joints  is investigated  by  considering  changes  in  natural  frequencies.  For  this  purpose,  numerical  and  experimental  modal analyses  are  carried  out  on  related  physical  model  of  a  pier  type  structure.  When  numerical  results  are  evaluated, natural  frequencies  generally  do  not  match  the  expected  experimental  results.  Uncertainties  in  different  aspects  of engineering  problems  are  always  a  challenge  for  researchers.  The  numerical  models  which  are  constructed  on  the basis of highly idealized scheme may not be able to represent all of the physical aspects of the physical one. For this study,  determination  of  percentage  of  semi-rigid  joints  is  considered  as  an  optimization  problem  based  on  the numerical and experimental frequencies. Probabilistic sensitivity analysis is also used to determine the search space. A new technique of optimization problem is solved by a combination of smart particle swarm optimization (PSO) and  genetic  algorithms,  and  a  complicated  and  efficient  system  for  model  updating  process  is  introduced.  It  is observed that the hybrid PSO-Genetic algorithm is applicable and appropriate in model updating process. It performs better than PSO algorithm, considering the good agreement between theoretical frequencies and experimental ones, before and after model updating. Key words: pier structure, probabilistic sensitivity analysis, hybrid PSO-Genetic algorithm, dynamic characteristics Citation: Mojtahedi, A., Baybordi, S., Fathi, A., Yaghubzadeh, A., 2020. A hybrid particle swarm optimization and genetic algorithm for model updating of a pier-type structure using experimental modal analysis. China Ocean Eng., 34(5): 697–707, doi: https://doi.org/10.1007/s13344-0200060-2

1 Introduction Investigation  on  the  behavior  of  the  coastal  structures needs an accurate study on the complicated dynamic conditions  arise  from  the  harsh  marine  environment.  Inadequate knowledge of the dynamic conditions in different situations may  lead  to  major  structural  damages.  About  the  coastal structures,  in  view  of  the  unexpected  aspects  arising  from the  marine  environment,  there  are  numerous