THE NONDESTRUCTIVE INSPECTION OF A 1/2 SCALE CORVETTE HULL TEST SECTION AND A ROYAL NAVY ARCHER CLASS FAST PATROL CRAFT USING THE STRUCTURAL IRREGULARITY AND DAMAGE EVALUATION ROUTINE (SIDER)

摘要

The Naval Surface Warfare Center, Carderock Division has been investigating composite materials for ship hull applications. Four 1/2 scale corvette hull sections were manufactured and their UNDEX performance evaluated. A new nondestructive evaluation technique, which uses vibrational excitation, was utilized to inspect the hull prior to shock and after shock testing. This new technique developed at NSWCCD and the United States Naval Academy, Structural Irregularity and Damage Evaluation Routine (SIDER), was successfully used to determine the as manufactured quality, and changes in the structure caused by UNDEX testing. The SIDER procedure looks at an entire structure and identifies locations where there is variability in structural stiffness. These areas are either due to the variability of the structure itself, or are caused by damage. Areas of damage that resulted in delaminations, debonding of ribs and stringers, bulkhead to hull degradation and localized cracking were successfully identified and correlated with both visual and ultrasonic inspection. The SIDER technique was able to inspect the entire hull section in about 6 hours. In addition, this technique was recently used to inspect sections of two ship structures for the Ministry of Defence, U.K. This paper discusses the SIDER technique and the results of the SIDER testing on these large scale composite structural components.