EXPERIMENTAL INVESTIGATION OF PERFORATING MASONRY BRICK WALLS IN CENTER CORE REHABILITATION METHOD; DEVELOPMENT OF TECHNIQUES AND EQUIPMENT

An advantageous method for retrofitting of brick unreinforced masonry buildings is center core. In this method vertical holes with given intervals are perforated through the brick walls to the footing and then reinforcing steel bars are embedded in the holes and grout will be injected finally to create bond strength between wall and bars. This method would not affect inner and outer appearance of the building; therefore it would be suitable for historical buildings. It could be also achieved without thorough evacuation of the building from residents and furniture. However, the difficulty of conducting such deep boreholes in weak and thin brick walls especially of older buildings remains a serious challenge in the method. So a practical investigation was designed to investigate the feasibility of the method and develop the techniques and equipment needed. This article aims to report the results of the experiment. However, the main contribution of the study has been finding new drilling techniques, designing and testing of the best suited drilling bit which is particularly appropriate for boring brick walls without deterioration and cracking.