On the structural behavior of reinforced concrete walls exposed to fire

The present work deals with numerical simulations concerning the international benchmark "Vulcain tests on 3 Walls" regarding fire tests conducted in CSTB in Paris, France. To this aim, sequentially-coupled thermo-mechanical analyses have been performed on three reinforced concrete walls, characterized by different load levels and boundary conditions. The numerical results show that the imposed compressive load and boundary conditions significantly influence the magnitude of the displacements. In the case of simply supported walls, the wall with the lower load level exhibited a gradual and monotonic increase of the displacements at mid-height (both in the tests and in the numerical analyses), while the wall with the higher load level exhibited a displacement reversal due to second-order effects after approximately 60 minutes of fire exposure. This reversal, which was obtained in the analyses, was not observed in the test. Load bearing capacity of all the three specimen walls was maintained in such a way that the collapse did not take place during two hours of fire exposure.