ESTIMATION OF FAILURE MECHANISM OF RC HOLLOW BRIDGE COLUMN WITH RUBBER BEARING DAMAGED BY THE 2016 KUMAMOTO EARTHQUAKE

Abstract

 The 2016 Kumamoto earthquake caused severe damage of civil infrastructures, including bridges which were constructed after 1995 Kobe Earthquake. The aim of this study is to estimate the failure mechanism of RC hollow bridge columns with rubber bearings. In our field survey, the typical crack pattern of the RC hollow columns and a land slide in the mountain beside the bridge were observed. In order to clarify whether the main factor causing the damage is the strong ground motion or the land slide, static analysis was conducted and the results were compared with the measurement after the earthquake. This research revealed that the main factor is the inertial force acting on the bridge column and it has the possibility to rupture the rubber bearing on the column.