15285

1487 دكتري

دكتري

سازه

اصفهان : دانشگاه صنعتي اصفهان

1398

هشت، 218، 13ص.: مصور (رنگي)، جدول، نمودار

مجتبي ازهري، محمد مهدي سعادت‌پور

سعيد صرامي فروشاني

بيژن برومند، محمود كدخدايي، حميد بهشتي، بشير موحديان عطار

1398/08/21

كتابنامه

عمران

مهندسي عمران

1398/08/22

2577584

Abstract In recent decades many studies have been done on combining the finite element FE method with meshfree methods but there is few research on combining the finite strip FS and mesh free methods Therefore in this thesis the combination of the classical FSmethod with the element free Galerkin EFG method is expressed For this purpose aftergiving an overview in Chapter 1 the EFG method are described in Chapter 2 with threeshape functions Then in the third chapter FS methods are described In this thesis theclassical FS with three trigonometric functions have been used in the longitudinal directionof strips In Chapter 4 using Lagrangian multipliers and penalty functions two strategiesare presented to combine the EFG and classical FS methods The coupling method is usedto solve linear and nonlinear static problems The results compared with other referencesshowed that the coupling method has good accuracy and the time of analysis can bereduced more than 50 Also for simply supported boundary condition the time ofanalysis reduced more than others Moreover the accuracy of the results can be increasedby connecting the strips transversely to the EFG sub domain than their longitudinalconnection In the fifth chapter the free vibration analysis of plates with differentgeometries is presented The results show that this method is suitable for the analysis ofsuch problems One of the disadvantages of the EFG method for solving the final system ofalgebraic equations is ill conditioned that occurred to solve eigenvalue problems with highratios of length to width approximately 10 It can be solved using improved EFG method This method increases the analysis time and is therefore best used if needed Finally inChapter 6 the coupling method is applied to the buckling and postbuckling problems ofplates and channel sections with web openings The results of this chapter not only confirmthe results of previous seasons but also show that the coupling method is effective foranalyzing channel sections The results also showed that the presence of openings reducedthe critical loading of the channel so that in the local distortion and general bucklingareas the critical moment were reduced approximately 9 to 34 3 to 21 and 3 to 13 percentin the channel with web openings than the channel without web openings respectively Keywords Finite strip method Eelement free Galerkin method Coupled element freeGalerkin finite strip method Lagrangian multiplier method Penalty function method

مجتبي ازهري، محمد مهدي سعادت‌پور

سعيد صرامي فروشاني

بيژن برومند، محمود كدخدايي، حميد بهشتي، بشير موحديان عطار