Perpustakaan Digital ITB

This study models the static load behavior of a High-Pressure Jack-up Drilling Riser (HPJDR) in the Natuna Sea to develop a transparent, spreadsheet-based alternative to finite element (FE) software. Top tension, bending moment, and von Mises stress unity ratio were calculated using fundamental solid mechanics. The static bending moment was calculated using the shooting method, while dynamic environmental effects were incorporated using a Dynamic Amplification Factor (DAF) derived from cubic polynomial regression. Results demonstrate that a 267.54 kips top tension prevents compressive buckling by maintaining a positive effective tension. Although pure static calculations underestimated the FE benchmarks, applying the calibrated DAF brought the profiles into high mathematical correlation with the software benchmark, achieving R 2 values ranging from 0.9810 to 0.9983. Sensitivity analyses established the model's domain of validity. Increasing the overpull from 50 kips to 100 kips reduced the maximum static bending moment by 2.8 kN.m and required DAF recalibration. Conversely, varying the internal mud weight from 11.0 ppg to seawater density only altered the maximum static bending moment by 0.24 kN.m and successfully maintained the calibrated DAF. Ultimately, despite limitations regarding deflected case and fatigue, this simplified model is an accurate and efficient tool for rapid crosschecking in field drilling operations.