## 1 Introduction  
For millennia, masonry has been a foundational construction material globally, contributing significantly to the built environment. Evidenced in some of the most notable historical structures, masonry stands as a testament to the ingenuity and enterprise of ancient cultures throughout history. Masonry has evolved significantly over time, witnessing numerous enhancements in both the constituent materials and the functional role of masonry elements as structural components. Nevertheless, the application of infill panels constructed from traditional Unreinforced Masonry (URM) is constrained in seismic regions due to inadequate ductility. Masonry is a composite material comprising solid or hollow blocks, mortar or mortar-less joints, grout, and reinforced bars, each exhibiting distinct material properties [1, 2]. The interfaces between masonry units serve as vulnerable planes due to their limited tensile and shear bond strength in traditional masonry [3]. This susceptibility can result in failures, often yielding catastrophic consequences such as loss of life and irreparable damage to structures, as shown in Figure 1. Damage is observed in traditional masonry structures during earthquakes due to their inefficiency in dissipating the seismic energy introduced [2]. To enhance the energy dissipation capacity of masonry, certain researchers explore investigations involving mortarless constructions (dry-stacked masonry), while others introduce interlocking mechanisms between brick units (interlocking masonry). Dry-stacked masonry consists of assembling bricks or blocks without mortar, resulting in a distinct contact behavior between masonry units compared to traditional masonry with mortar. Noteworthy ancient dry-stack masonry structures, such as the pyramids in Egypt and the ruins in Zimbabwe, continue to exist [4]. These structures, having withstood numerous seismic events, demonstrate ongoing structural stability and integrity, affirming the resilience of dry-stacked masonry against seismic forces. [PERSON] et al. [5] and [PERSON] et al. [4] conducted research on both in-plane and out-of-plane seismic behavior of masonry walls, culminating in the development of an interlocking block termed Hydraform Interlocking Dry-Stack Block. Their findings suggest that the strength of dry-stack units does not significantly impact the resistance to lateral loads. Instead, the lateral load-bearing capacity of dry-stack masonry is contingent upon the effectiveness of the interlocking mechanism and inter-brick friction within the infill panels. To enhance the energy dissipation capabilities of framed masonry structures, a novel concept in framed masonry panels constructed with mortar-less semi-interlocking units has been developed at the University of Newcastle, Australia [8]. It is referred to as a Semi-Interlocking Masonry (SIM) system, which introduces units in masonry infill panels (SIM panels) designed for relative sliding in-plane while interlocking to prevent relative sliding out-of-plane. As a result, the SIM panel exhibits reduced stiffness and susceptibility to damage, simultaneously amplifying its ability to dissipate seismic energy. Two distinct types of SIM units (230 mm long, 100 mm thick, and 76 mm high) have been created: topological and mechanical, as illustrated in Figure 2[9]. Topological SIM units leverage the natural contours of the units to facilitate in-plane movement, while mechanical SIM units employ a system of slots and sockets to allow controlled in-plane movement [10; 11]. The initial design of the SIM system envisioned it as a dry stack, meaning the structure would be assembled solely with blocks without mortar. However, practical concerns emerged, particularly related to water penetration and thermal properties. [PERSON] et al. [11] conducted an investigation into the water penetration and thermal insulation performance of SIM panels using various joint fillers, such as linesed oil-based putty and tape, between the units.