Structural Integrity of an Onshore Oil & Gas Platform due to Increasing Seismic Effect in Malaysia

The increasing seismic activity form the Sumatran fault line raises uncertainties as most of the current structure in Malaysian Oil and Gas Industry are designed for seismic hazard in Zone 1 (Ground Acceleration = 0.075g) according to Uniform Building Code 1997 (UBC 1997) due to the factor that Malaysia is in the low seismic hazard zone. This study is to determine and compare the connection design for steel structure if the seismic zone in Malaysia increases from Zone 1 to Zone 2A (0.015g) and Zone 2B (0.2g). This study is carried out by simulating and modelling the existing Packinox gas vessel steel support structure in StaadPro V8i. By manipulating the seismic ground acceleration coefficient, the most critical joint resulting from the increasing ground acceleration factor is obtain. These critical forces induced on the joints are then used to design a simple bolted connection and used to compare the difference in the connection for higher seismic zones. As a result, it was found that the increasing ground acceleration factor from zone 1 to zone 2A does not effect the most joints with increase up to 9.42% and 5.23% for axial and tie force respectively. However, for Zone 2B, there are significant increase in the forces induced at the critical joints with increase up to 38.35% and 12.61% for axial force and tie force respectively.