Analysis of Structural Response And Member Utilization For The Lower Deck And Wellhead Access Platform- Nfq14 Topside During SPMT Transportation

Abstract

Transporting large offshore structures requires rigorous safety analysis. This research examines the structural response of the Lower Deck and Wellhead Access Platform (LD&WAP) for the NFQ14 Topside, part of Qatar's North Field Expansion Project, during its transport via Self-Propelled Modular Transporters (SPMTs). The study verifies the platform's integrity under static loads, including the impact of a shifted Center of Gravity (COG). A 3D model was developed in SACS using dead loads from TEKLA models and the Weight Control Report (WCR). Load combinations simulated worst-case scenarios. A static linear analysis determined maximum joint reactions and member utilization (Unity Check), with results benchmarked against the AISC design code. The analysis confirmed the platform's system is robust. The maximum joint reaction was 159.83 metric tons under a shifted CoG, within the SPMT's capacity. The highest member utilization was 0.99, indicating an efficient but near-capacity design that requires monitoring. These findings validate the transportation plan and static analysis approach, ensuring the safe transport of the LD&WAP and offering a framework for future projects.