Repair of Beam End Joints Using Steel Rods and Wood Prosthesis in Heritage Buildings: Implantation in the Structure of the Zabala Palace in Ordizia (Basque Country, Spain)

This paper presents the methodology developed in the repair of three oak beam ends in a protected heritage building: the Zabala Palace in Ordizia (Basque Country, Spain). It describes the structural assessment, design, calculation and execution process, as well as the experimental tests carried out in the laboratory to verify and validate the structural capacity of the repair method. The intervention consisted of cutting and removing the beam ends degraded by fungi and replacing them with wooden prostheses. These elements were connected to the beams by means of threaded steel rods and epoxy resin. Calculations based on standards and the literature were verified by laboratory tests where aspects such as the fluidity, filling and pull-out resistance of four commercial epoxy resins were tested. Once the epoxy resin was selected, three samples of the reinforcement design were also flexure tested. The results of the different tests show capacities much higher than those resulting from the application of the calculation procedures in the current bibliography and standards. The implemented solution allowed the conservation of most of the original patrimonial timber, following the criteria of minimum intervention.