Electronic Theses and Dissertation

Tangki penyimpanan banyak digunakan dalam dunia industri dan memiliki peranan penting untuk kelancaran bisnis. Tangki eksisting umumnya ditemukan kerusakan berupa korosi setelah tidak beroperasional selama bertahun – tahun, begitu pula yang dialami oleh tangki HSD (High Speed Diesel). Agar dimanfaatkan kembali, maka perlu untuk melakukan evaluasi kekuatan, kestabilan, dan kelayakan perilaku struktur tangki ini guna menghindari resiko kegagalan dan bahaya. Penelitian ini bertujuan untuk menyelidiki kekuatan, kestabilan, dan perilaku struktur tangki dengan pedoman dan syarat standar tangki Internasional API 650:2020, juga standar nasional SNI 1727:2020 dan SNI 1726:2019. Objek penelitian adalah tangki eksisting HSD F-6302 berlokasi di Lhokseumawe. Analisis dilakukan dengan cara simulasi metode elemen hingga untuk berbagai kondisi pembebanan. Simulasi diimplementasikan pada tiga kondisi, yakni inspected, manufactured, dan redesign serta mengakomodasi dua jenis model matematis, yakni add load approach dan add mass approach. Hasil penelitian memperlihatkan bahwa tangki kondisi inspected dan manufactured sudah tidak aman dengan nilai tegangan ekuivalen maksimum sebesar 276,32 MPa dan 271,30 MPa melebihi tegangan izin sebesar 182,62 MPa. Kedua model ini stabil terhadap angin, namun tidak stabil terhadap gempa dimana rasio pengangkuran masing–masingnya sebesar 3,21 dan 3,18 melebihi batas kestabilan sebesar 1,54. Kedua model awal ini masih memenuhi syarat perilaku struktur, dimana secara berturut – turut perpindahan lateral maksimum mereka sebesar 13,218 mm dan 12,921 mm kurang dari perpindahan izin sebesar 60,96 mm. Direkomendasikan tangki redesign dengan penggantian konfigurasi ketebalan cangkang dan penambahan angkur. Hasil ini telah memberikan kondisi yang memenuhi kriteria API 650:2020 dan tangki dapat digunakan kembali.

Storage tanks are widely used in the industrial world and have an important role in the smooth running of the business. Existing tanks are generally found damaged in the form of corrosion after not operating for many years, as is experienced by the HSD (High Speed Diesel) tank. In order to be reused, it is necessary to evaluate the strength, stability, and feasibility of the structural behaviour of this tank to avoid the risk of failure and danger. This research aims to investigate the strength, stability, and behaviour of the tank structure with the guidelines and requirements of the API 650:2020 International tank standard, as well as the national standards SNI 1727:2020 and SNI 1726:2019. The object of research is the existing tank HSD F-6302 located in Lhokseumawe. The analysis was carried out by simulating the finite element method for various loading conditions. The simulation was implemented in three conditions, namely inspected, manufactured, and redesigned, and accommodated two types of mathematical models, namely the add load approach and add mass approach. The results showed that the inspected and manufactured condition tanks were unsafe with maximum equivalent stress values of 276.32 MPa and 271.30 MPa exceeding the allowable stress of 182.62 MPa. Both models are wind stable, but earthquake unstable with anchorage ratios of 3.21 and 3.18, respectively, exceeding the stability limit of 1.54. Both initial models still meet the structural behaviour requirements, as their maximum lateral displacements of 13.218 mm and 12.921 mm are less than the allowable displacement of 60.96 mm, respectively. It is recommended that the tank be redesigned by changing the shell thickness configuration and adding anchorages. These results have provided conditions that fulfil API 650:2020 criteria and the tank can be reused.