Seismic Assesment Of Simply Supported Vs Continuous Concrete Girder Bridges (case Study Of Selected Bridges)

Seismic evaluations of typical concrete girder bridges are conducted for two existingrnsimply supported bridges, which are common to the Ethiopian highway construction, andrnfor their counterpart continuous girder bridges. These evaluations are performed for anrnapproximate hazard level of 0.1g ground acceleration by performing linear modalrnresponse spectrum analyses on three-dimensional analytical models. The results showrnresponses in the deck girder, reinforced concrete columns and bearings at the supports ofrnthe girders. In general, the longitudinal loading of the continuous bridges results in largerrndemands than the transverse loading. Consequently, the continuous nature of the deckrntends to transfer seismic demand to different structural components. Therefore, therndemands of piers for continuous girder bridges become larger. The simply supportedrnbridges sustain bearing deformations in the transverse direction which are of the samernvalue as the longitudinal response. These results suggest that both longitudinal andrntransverse loading are significant and should be considered when performing seismicrnassessment of these bridges. And also the modal response spectrum analysis result showsrnthat the contribution of higher modes in seismic response of the continuous bridges isrninsignificant. Whereas it is noted that, the contributing higher modes should be consideredrnto obtain the seismic responses of simply supported girder bridges.

Get Full Work

Report copyright infringement or plagiarism