evaluasi jembatan di sungai boyong yogyakarta pasca erupsi gunung merapi 2010

Mount Merapi is one of 129 active volcanoes in Indonesia with high frequent of eruptions. The 2010 Mount Merapi eruption on October 26th was the biggest disaster compare to similar disasters in the five previous period before. Cold lava flow as the continous impact of the eruption potentially could damaging the bridges along the rivers that disgorge at Mount Merapi, one of them is Boyong river. The Boyong river downstream was crossing the center of Yogyakarta city. The fears of after eruption damage againts bridges along the Boyong River channel and limited government funds on restoring the bridges function and condition encourage the preparation of priorities scale to determine which bridge should be addressed first. Both primary and secondary data were collected and a comprehensive damage assessment refers to the Bridge Management System standard was conducted in order to compile further evaluation and bridges priorities formulation. The impact of Mt. Merapi eruption in 2010 against the bridges along Boyong river resulted in the highly increasement of riverbed sediment and cause damage againts the Ngentak, Plemburan, Boyong and Gemawang bridge’s retaining wall. In terms of safety on structure, all bridges along the Boyong river still can be passed safely except Wonosobo bridge and Kemiri bridge. The order of bridge jandling priority on A class bridges, ie the bridges of Tungkak, Boyong, Sudirman, and Code; while on B class bridges, ie the bridges of Ngentak, Guava, Sayidan, Wirosaban, Juminahan, Sardjito I, Wirosaban, Kewek, Wreksodiningrat and Krikilan Pulowatu; On C class bridges, ie the bridges of Pecan, Wonosobo, Plemburan, Gemawang and Rejodani