Seismic Experimental Analysis of a Full-Scale Steel Building with Passive Fire Protections

The paper describes the results of an experimental campaign on the seismic behaviour of a full-scale concentrically braced steel frame designed according the EC8 and equipped with different types of passive fire protection. In this respect, fire protection boards made of calcium silicate and mineral spray-based fire protections were applied to dissipative members, such as the bracings, and to non-dissipative elements, such as one column of the bracing system. Two solutions of calcium silicate fire protection boards were employed: (i) a standard solution and (b) an improved solution conceived for seismic applications. Moreover, the external bays of the specimen equipped with mineral spray-based fire protections were filled with two fire walls both of them made of concrete blocks without and with seismic detailing, respectively. In total 10 tests on 4 frames, that also include a first test of the bare frame, were performed, and for each test different seismicity levels were applied. The hybrid simulation technique was used to maintain the relevance and accuracy of a full-scale test and also to optimize the use of the available test facilities. In this respect, only the ground floor of the prototype structure was physically tested in the laboratory, whereas the remainder of structure was numerically simulated. The tests showed that the fire protections and the fire walls did not suffer major damage owing to cyclic loading. Indeed, the damage was not likely to significantly affect the fire performance. The outcomes of the experimental results of all the tests are thoroughly described in the paper.