000020269 001__ 20269
000020269 005__ 20170118182406.0
000020269 04107 $$aeng
000020269 046__ $$k2017-01-09
000020269 100__ $$aDailamani, Shadi Ostovari
000020269 24500 $$aAccuracy of Modal Combination Methods in Seismic Design of Barrel Vault Cylindrical Roof Shells

000020269 24630 $$n16.$$pProceedings of the 16th World Conference on Earthquake Engineering
000020269 260__ $$b
000020269 506__ $$arestricted
000020269 520__ $$2eng$$aThe design of a structure using modal analysis is usually based on finding the maximum responses using one of the two combination methods of square-root-of -sum-of-squares (SRSS) and complete quadratic combination (CQC). It is generally accepted that the predicted approximate responses would be conservative and accurate enough for practical structural design analysis. However, in this paper it is shown that for barrel vault cylindrical roof shells the modal combination methods may not result in conservative results. In this paper a semianalytical method, which has been previously verified using a finite element modelling, is used to find the time history response when barrel vault cylindrical shells are subject to synchronous vertical motions from typical earthquake records. The analytical method adopts an explicit solution based upon the Love-Timoshenko straindisplacement relationships and employs a Lagrangian approach to the derivation of the equations of motion. The investigation on the accuracy of modal combination methods using the two methods of square-root-of-sumof-squares (SRSS) and complete quadratic combination (CQC) shows that both methods estimate the maximum displacement and axial membrane stresses within the practically acceptable percentage of error. However, the stress resultants other than the axial membrane stress cannot be accurately estimated using these modal combination methods and they do not always provide conservative results. It is concluded that performing a modal combination methods could lead to serious underestimation of responses for large roof shells subjected to earthquake loading.

000020269 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000020269 653__ $$aRoof shells; modal combination methods; seismic design; higher modes; earthquake loading

000020269 7112_ $$a16th World Conference on Earthquake Engineering$$cSantiago (CL)$$d2017-01-09 / 2017-01-13$$gWCEE16
000020269 720__ $$aDailamani, Shadi Ostovari$$iCroll, James
000020269 8560_ $$ffischerc@itam.cas.cz
000020269 8564_ $$s533871$$uhttps://invenio.itam.cas.cz/record/20269/files/877.pdf$$yOriginal version of the author's contribution as presented on USB, paper 877.
000020269 962__ $$r16048
000020269 980__ $$aPAPER