Predictive Methods for the Fire Resistance of Single Skin and Sandwich CompositeMaterials

摘要

Polymer composite materials are becoming increasingly popular in many engineeringstructures in the civil, aerospace, marine and automotive industries. The increasedstrength and stiffness to weight ratios which are possible with certain types ofcomposites make them particularly attractive to many high performance applicationssuch as military aircraft, offshore lifeboats and formula one racing cars.One aspect of composite materials which is preventing more widespread use is theperceived poor performance in fire. The perception is due to the fact that organiccompounds used in polymer composites are combustible. The loss of the NorwegianNavy’s composite mine hunter vessel Orkla in 2002 to a fire did much to preventfurther widespread use of such materials.The work presented here describes the research that has been conducted into assessingand predicting the performance of single skin and sandwich composite materialssubjected to fire and mechanical load. The materials that were investigated wererepresentative of the materials used in the construction of Royal National LifeboatInstitution (RNLI) lifeboats.A new method has been developed to assess the response both thermally andmechanically of single skin and sandwich panels subjected to combined fire andmechanical load. This has been done by the construction of a small scale fire and loadtesting apparatus. An empirical relationship was developed to predict the stiffness ofsingle skin and sandwich panels during a fire and load test.Numerical models have also been generated to predict the thermo-mechanical responseof single skin and sandwich panels to fire and load. Testing of single skin and sandwichpanels on the newly developed apparatus has been conducted to verify the numericalmodels.The numerical models and the empirical relationship were used to predict the responseof a full scale composite sandwich panel, representative of a lifeboat deck, to a standardcellulosic fire and mechanical load.