Non-invasive methods for testing the integrity of bulkheads and/or deckheads during a fire

The project aimed to investigate and evaluate a possible non-invasive test method to assess the integrity of bulkheads and/or deckheads during a fire. Currently there is not an accurate method for determining the integrity of a bulkheads and/or deckheads during a fire on-board a ship. This leads to a higher risk being placed on fire fighters. A literature review was conducted, following which it was determined that Air Coupled Ultrasonics (ACU) was the most viable non-invasive test method for the project. Optimisation of the ACU test method was conducted for use under fire conditions. Aluminium, GFRP and CFRP plates were placed under fire conditions using a LPG bottle and burner. The plates underwent ACU testing at 10ºC increments. Results were evaluated in relation to suitability for use of the chosen non-invasive test method, impact of temperature on results and material properties, and structural integrity issues. The results showed the lamb wave velocity greatly changed as the elastic properties of the material changed due to the thermal loading on the plates caused by the fire. Even though the results showed that the lamb wave velocity greatly changed as the material underwent a significant change in elastic properties, before ACU is suitable for in-service implementation, further research and development is required. Further research and development is required into ultrasonic transducer bandwidth, waveform generator pulse, oscilloscope, depth of penetration and portability to ensure accuracy and reliability in results