STUDI PERENCANAAN STRUKTUR BAWAH MELIPUTI ABUTMENT, PILAR, DAN PONDASI TIANG PANCANG PADA JEMBATAN NGADI KABUPATEN KEDIRI

The Ngadi Bridge is planned with a span on the north side of 12 meters and on the south side of 35 meters. This Ngadi Bridge has a total span of 47 meters consisting of 2 abutments and pillar with the main structure being reinforced concrete with a 35 meter span girder using (PCI Girger) while at a span of 12 meters using WF 700.300.13.24 Steel girder. This Ngadi Bridge uses a concrete pile foundation (concrete Piles), and the pile diameter dimensions are 80 cm. In this re-planning there will be changes in foundation dimensions and depths by looking at the existing conditions above to obtain an adequate and efficient soil bearing capacity. Calculation of upper structure loading refers to SNI 1725-2016. SPT testing is carried out to a depth of 30 m and it is known that the existing soil type is dominantly silt. In this design, a spun pile type abutment foundation with dimensions of 0.8 m and a depth of 16 m is used as many as 15 pieces, while the abutment dimensions are planned to have a height of 6 m with a length of 12 m. The breast wall uses 60D25 bending reinforcement and D19-250 shear reinforcement. The pile cap dimensions are 12 m long and 6 m long with D25-100 flexural reinforcement and D19-250 shear reinforcement. Meanwhile, the pillars are 10 m high and 12 m long. The bearing capacity of the foundation is declared safe with the obtained value of Qu = 165.151 tons > Pmax = 163.126 tons. The total decrease that occurred was 5.27 cm. In this design, 15 spun pile pillar foundations with a dimension of 1 m and a depth of 13 m were used. Pier head used 2D25-100 flexural reinforcement and D16-250 shear reinforcement. Pier wall uses 88D25 flexural reinforcement and D16-250 shear reinforcement. The pile cap dimensions are 12 m long and 6.2 m wide. Flexural reinforcement D25-100 with reinforcement for D19-200 is used. The bearing capacity of the foundation is declared safe with the obtained value of Qu = 229.783 tons > Pmax = 215.591 tons. The total settlement that occurred was 2.76 cm.