Experimental study of reinforced masonry using veneer in steel frames

Abstract

This work aims to analyze the behavior of steel frames filled with concrete block masonry and reinforced using the jacketing technique, employing welded or bolted beam-column connections and subjected to cyclic lateral loading.  The load capacity, stiffness, and energy dissipation are compared based on data from previous tests conducted at the Housing Research Center of the National Polytechnic School. Two different prototypes were used: Prototype I consisted of two columns made of concrete-filled rectangular tubes, an I-section beam, and welded connections, while Prototype II consisted of I-section columns and beam with bolted connections. For both prototypes, one case involved applying moderate pre-damage to the original masonry, equivalent to that produced by a medium-intensity earthquake, followed by reinforcement. In the other case, the masonry was initially reinforced without any prior damage. This reinforcement consisted of placing a welded wire mesh on each face of the masonry and anchoring it to the surrounding frame, then covering it with a layer of mortar. These prototypes were subjected to quasi-static lateral load tests, obtaining capacity curves, stiffness, and energy dissipation data. Finally, the comparison showed that the undamaged variant of Prototype I had a capacity 1.34 times greater than that of Prototype II, while the pre-damaged variant of Prototype I had a capacity 1.18 times greater than that of Prototype II.