EVALUASI KINERJA STRUKTUR JEMBATAN INTEGRAL DARI PERUBAHAN STRUKTUR JEMBATAN PARSIAL

Abstract

The Serpong-Balaraja Section 1A toll road construction project's Foresta bridge structure had a modification in span length from 40 meters to 41,386 meters without changing the girder's specifications. The structural system switches from partial bridges to integrated beams to reduce the number of field moments caused by span changes. With the change in the structural system, it is necessary to evaluate the performance of the bridge structure with an integral system by checking the cross-sectional capacity, comparing the negative moment resisting reinforcement from the analysis with the existing conditions, and determining the reinforcement that can be used if the integral bridge is inadequate. With the help of software, evaluation is carried out by checking the ability of the cross section to withstand moments and checking its deflection and shear forces. Based on the results of the analysis, the moment capacity of the middle section is 18198.38 kN.m., and the moment of the load capacity is 7829.824 kN.m. This indicates that the middle capacity has been in service. With a load moment capacity of 11335.04 kNm and an end cross-sectional capacity of 9401.26 kN.m, the performance of the cross section is not serviceable. In addition, the bridge deflection meets the allowable deflection limit of 51.73 mm after the bridge is integrated because previously the partial bridge deflection was 79.83 mm, and after being integrated, it became 23.28 m. Furthermore, the shear forces of the partial bridge (1599,162 kN) and the integral bridge (1585,009 kN) are less than the maximum shear force that can be carried, which is 6934,12 kN. Based on the analysis results, D32-100 negative moment resisting reinforcement is needed, while the existing condition reinforcement uses D32-150. This indicates that the structure requires reinforcement. Fiber-reinforced polymer (FRP) was chosen as reinforcement in reference to 022/BM/2011 because it is superior in several ways.