Restoration and strengthening of the old building of Aland Maritime Museum in Mariehamn, Finland

Original slabs with low strength concrete formed and poured in 1946 were tested in 2010 by several practical methods. The failure capacity of the tested slabs was analyzed by yield line theory. Results illustrated that one slab was disintegrated, in a deteriorated state and needed to be replaced. The remaining four slabs had to be strengthened by special concrete topping in order to increase their stiffness against floor vibration. The building of Aland Maritime Museum and its cultural resource and value were taken into account in decisions related to the restoration work to retain integrity and authenticity of the structure.