Analisis Perilaku Girder Akibat Jacking serta Peninjauan Keselamatan Pekerjaan pada Pelaksanaan Erection Girder Fase 2 Proyek Tol Becakayu Seksi 2A Ujung

Idam Setiadi, Dr. Ir. Inggar Septhia Irawati, S.T., M.T., IPM.

2025 | Skripsi | TEKNIK SIPIL

Dalam pekerjaan erection girder parameter keselamatan pekerjaan menjadi perhatian utama sehingga setiap langkah pekerjaan perlu dilakukan kajian dan analisis secara menyeluruh. Pekerjaan erection Steel Box Arch (SB Arch) girder Ahmad Yani terbagi ke dalam tiga fase dimulai dari erection girder fase 1, fase 3, dan diakhiri oleh fase 2. Pelaksanaan erection girder fase 3 mengalami penundaan selama 10 bulan sehingga girder fase 1 yang telah terereksi sebelumnya mengalami pergeseran ke arah backwall karena faktor kemiringan girder dan gravitasi bumi. Untuk mengembalikan posisi girder fase 1 ke posisi semula dilakukan pekerjaan adjust untuk setiap girder menggunakan hydraulic jack kapasitas 50 ton.  Analisis perilaku girder SB Arch akibat jacking dilakukan untuk memastikan keselamatan girder akibat gaya jacking yang sifatnya terpusat. Pekerjaan erection girder dilakukan dengan menggunakan single crane kapasitas 800 ton sehingga diperlukan landasan crane untuk menjaga stabilitas crane saat beroperasi. Selain itu, untuk memastikan keselamatan pekerjaan adjust girder fase 1 serta erection girder fase 2 dilakukan identifikasi bahaya, penliaian risiko, dan bentuk pengendalian risiko pekerjaan yang disusun dalam tabel Hazard Identification Risk Assesment and Determining Control (HIRADC).
SB Arch girder memiliki bentuk penampang anisotropic sehingga diperlukan software berbasis metode elemen hingga untuk melakukan analisis perilaku girder akibat proses jacking. Software yang digunakan untuk proses modeling dan analisis adalah Solidworks. Analisis perilaku girder dilakukan pada sampel uji berupa girder dengan berat sendiri maksimum. Penentuan dimensi landasan crane dilakukan dengan analisis kuat dukung tanah serta analisis penurunan segera. Analisis tersebut dilakukan berdasarkan data hasil uji beban pelat di lapangan. Penyusunan bentuk pengendalian risiko pekerjaan dalam tabel HIRADC dilakukan berdasarkan hasil pengamatan di lapangan dan mengacu pada Permen PUPR Nomor 10 Tahun 2021.
Berdasarkan hasil analisis menggunakan software Solidworks, didapatkan nilai Von Misses stress maksimum sebesar 84,447 MPa yang terletak pada bagian crossbeam dengan nilai safety factor sebesar 2,309. Dengan nilai safety factor miminum sebesar 1,51 yang diambil dari kondisi batas elastis material baja sebesar 0,66 dari nilai tegangan lelehnya maka perilaku girder sepenuhnya masih berada dalam batas elastis. Berdasarkan hasil analisis kuat dukung tanah dan nilai penurunan segera digunakan landasan crane ukuran 6x18 meter dengan nilai SF sebesar 12,251 dan penurunan maksimum yang terjadi sebesar 0,392 mm serta batas penurunan izin sebesar 1,138 mm pada titik PBT 5. Selain itu, berdasarkan tabel HIRADC, risiko akhir dari setiap item pekerjaan berada pada kategori low risk sehingga pekerjaan adjust girder fase 1 dan erection girder fase 2 telah memenuhi standar keselamatan kerja.

In girder erection work, safety parameters are the main concern so that every step of the work needs to be thoroughly studied and analyzed. The Ahmad Yani Steel Box Arch (SB Arch) girder erection work is divided into three phases starting from phase 1 girder erection, phase 3, and phase 2. The erection of phase 3 girder postponed for over 10 months so that the phase 1 girder that had been erected previously experienced a slide towards the backwall due to the earth's gravity and the girder’s orientation. To return the phase 1 girder to its original position, girder adjust was carried out for each girder using a hydraulic jack with a capacity of 50 tons. Analysis of the SB Arch girder performance due to jacking was carried out to ensure girder safety due to the jacking force. Girder erection work is carried out using a single crane with a capacity of 800 tons so that a crane pad is needed to maintain its stability. In addition, to ensure the girder adjust phase 1 and erection girder phase 2 safety, hazard identification, risk assessment, and risk control forms are composed in the Hazard Identification Risk Assessment and Determining Control (HIRADC) table.
SB Arch girder has anisotropic section properties so that finite element method-based software to analyze girder behavior due to the jacking process is needed. Solidworks is used for modeling and analysis process with a maximum self-weight girder is being used as a sample in the analysis of girder behavior. The design of the crane pad is performed by analyzing the ground bearing capacity and the immediate settlement of the soil. The analysis was carried out based on the plate bearing test data. The formulation of HIRADC table is performed based on the author’s observations and refers to Permen PUPR Nomor 10 of 2021.
Based on the analysis results using Solidworks, the maximum Von Misses stress value of 84.447 MPa which is located in the crossbeam section and thus a safety factor value of 2.309 is obtained. With a miminum safety factor value of 1.409 taken from the elastic limit condition of steel material by 0.66 of its yield stress value, the girder behavior is still within the elastic limit. Based on the analysis results of the bearing capacity of the soil and the immediate settlement, a crane pad with a size of 6x18 meters is used with a safety factor of 12.251 and maximum settlement of 0,392 mm with allowable settlement of 1.138 mm. Based on the HIRADC, the final risk for each work items are on the low risks category so that the adjust girder phase 1 and erection girder phase 2 satisfy work safety standards.

Kata Kunci : Steel Box Arch girder, Von Misses stress, faktor keamanan, landasan crane, uji beban pelat, HIRADC