Computational Aspects in Retrofitting Cracked Stone Structures by SMA Devices

The problem of retrofitting ancient stone or brick structures or structural components relies on the benefic role of the crack on the system response due to their dissipation ability. On the other side, cracks should not open indefinitely, otherwise the system itself fails. Such a problem characterizes the old Victorian brick bridges in UK, the dome of many Romanic and Gothic European churches, the accessibility to archaeological sites as well as the preservation of monuments made of monolithic stone blocks. For all these structural systems a well promising technology is to sew the cracked parts by pre-stressed elements in shape memory alloys (SMA). The alloys available for this purpose are discussed at the end of this paper which focuses its attention on the computational aspect related with such an implementation. It requires finite element displacement analyses, within the framework of contact problems, and the implementation of a suitable constitutive law for the selected shape memory alloy. Details on the different topics will be discussed with reference to the Southern Memnon Colossus, located in Luxor, Egypt. The study is part of the project CHIME (Conservation of historical monuments in the Mediterranean area) funded by EU.