The characteristic compressive strength of masonry walls with reconstituted limestone blocks from building waste

Abstract

Maltese Globigerina Limestone (GL) structures have distinctive aesthetical and traditional features which are immediately recognised from their colour, texture and construction method used. This makes GL the most common source of structural elements in local constructions. Malta has been experiencing an increase in construction in the last couple of decades. This means that not only new constructions are being built but, also, older buildings are being demolished in order to make way for new constructions which are able to adapt to the new demand. This means that a great amount of Construction and Demolition (C&D) waste is being generated every year with no intended reuse apart from being used as infill. The use of concrete blocks for masonry constructions has been the alternative construction material replacing natural stone blocks as it is a cheaper solution and provides more flexibility with respect to its manufacturing abilities. It is also an ever-evolving material which can adapt to new demands for the construction industry. This aforementioned statement leads to the initiation of the research by Buhagiar & Montesin (2010) for the use of C&D waste limestone powder subjected to a compression force inside different sized and shaped moulds for different testing procedures. Multiple studies for different aspects of this produced material have been explored. Since then the reconstituted stone mix has been adapted with respect to results achieved. This study is a continuation of research undertaken by Gatt (2011), Formosa (2012), Genovese (2013), Falzon (2013), Davison (2014) and Gatt (2016), where casts of reconstituted stone blocks are assembled into representative masonry walls and tested for their characteristic compressive strength. These are then to be compared with identical replicas of masonry walls constructed with natural stone blocks retrieved from the same quarry location that have been used for the previously conducted studies. Furthermore, a new variable, being different mortar mixes, are introduced as the binder in the construction of the masonry walls.