Experimental and analytical assessment on rubberized concrete interlocking grouted masonry walls under eccentric loading

Abstract

In this study, the concept of interlocking masonry is modified by introducing waste materials, fly ash (FA) and crumb rubber (CR), to overcome the issues of mortared walls and conventional interlocking walls. Therefore, this research is aimed to investigate the behavior of rubberized concrete interlocking grouted masonry walls (RCIGMWs) subjected to eccentric compression loading experimentally. Twelve RCIGMWs of size 1260 mm height × 625 mm width × 125 mm thickness were constructed, by stacking RCIBs in running bond on top of one another without the use of mortar layers, however, the center cores (holes) of the wall panels were filled by pouring the concrete grout into. RCIGMWs were then tested under four axial compression eccentric loading levels including e=0, e=t/6, e=t/3, and e=t/2.5 where the top of the wall panels was considered for eccentricity while the end was maintained flat as a fixed. The bottom support was fixed while the upper end was free. The structural responses including the efficiencyof the walls, axial displacement and lateral deformation, and failure mechanisms were investigated. The experimental findings show that higher compressive eccentricities adversely impacted the behavior responses of RCIGMWs. Under eccentricities greater than kern distance, walls suffered significant loss of their load-bearing capacity. Moreover, higher lateral deflection was recorded at higher eccentricity levels as a result of the developed wall’s bending moment. Vertical splitting failure was observed between the webs and brick shells, which was followed by localized spalling. A global buckling was formed at higher eccentricity levels where the wall bent and the dry bed joint at the upper height of the wall opened and failed prematurely. Analytically, the EC-6 and ACI-530 are able to calculate the load-bearing capacity of the RCIGMWs, however, they tend to underestimate it with increasing the eccentricity while BS 5628–1 provides approximately 90 % precision.