EVALUASI PENYEBAB KEGAGALAN DAN PERBAIKAN STRUKTUR JEMBATAN RANGKA BAJA DENGAN BENTANG 54 M Studi Kasus Jembatan Perusahaan Daerah Air Minum (PDAM) di Sungai Cisadane Kabupaten Bogor

One of the failure indicator of a bridge is a large deflection. As the truss bridge was owned by Regional Water Company (PDAM) Bogor Regency with span 54 m has deflection 42,5 cm. It was occurred when the buffer removed before the bridge load test, where the deflection has exceed the maximum requirement, according to SNI 03 1729 2002 is L/360 or 15 cm. The aims of this research to evaluate the structure performance and determine strengthening method, so that the bridge can be used again. The evaluation of bridge structure include collection secondary data in the form of a preliminary bridges design, steel material test results and primary data consisted of visual inspection in the field, dimensions measurement of the bridge and quality test of steel material. The data were used as input in structure modeling using SAP 2000 in order to calculate a required strength (Ru) of each structural members. Calculations were done to obtain the design strength (�Rn) of structural members and connections. The bridge components are categorized as safe condition if its design strength is greater or equal than required strength or �Rn � Ru, if not, the bridge is categorized as failure and then the repair method and strengthening would be performed. The result showed that all of structural members and connections are safe. Bridge failure is caused by factors of less precise execution in the field, combination of a large bolt holes and tightening bolts that have not reached the minimum tensile strength. The proposed bridge repair method is provide two pieces plates. The plates are welded on the end of the rod and perforated in accordance with the position of the existing bolt holes in order to avoid shifting the bolt