Experimental and numerical investigation on reserve strength of jackets with single diagonal and X brace configurations

Jacket framing arrangement X, K, V and single bracing systems used in jackets influence the ultimate strength and redundancy in the system. Experimental investigation was conducted on a 2D frame (1:20) with two different bracing patterns (2D-1 and 2D-2) the results are compared with that obtained from nonlinear pushover analysis. Parametric assessment of Reserve Strength Ratio has been carried out on three bracing patterns, namely 3D-A, 3D-B and 3D-C using non-linear pushover analysis including pile-soil interaction. It is observed that RSR increases by 15% for X brace configuration (2D-2) compared to single brace configuration (2D-1). The RSR for 3D-B is found to be higher by be 35 % and 12% compared to bracing patterns 3D-A and 3D-C respectively. The brace pattern 3D-C exhibits similar strength to 3D-B, illustrating the insignificance of the brace at the top bay and this leads to reduction in wave loads on the system.