## 1 Introduction  
The global increase in aging infrastructure has become a significant concern in recent decades [1, 2, 3]. Structures constructed during periods of rapid industrialization and urban development are now experiencing deterioration beyond their originally intended service lives [2, 4]. Over time, materials degrade due to environmental exposure, fatigue, chemical reactions, and other aging-related mechanisms [5, 6]. This degradation leads to the reduction of structural integrity, stiffness, and load-bearing capacity, compromising the overall safety and performance of the structures [7, 8]. Without timely intervention, the progressive deterioration of aging structures can result in serious functional deficiencies, higher maintenance costs, and eventual structural failures [9, 10]. Therefore, understanding the mechanisms of structural deterioration and developing strategies to mitigate their effects are essential to extending the service life and ensuring the reliability of existing infrastructure. This trend is also evident in South Korea, where the aging of buildings has become a growing concern. As of 2020, approximately 38.8% of all buildings in South Korea--equivalent to 7.27 million structures--had exceeded 30 years of age, and this proportion is projected to rise sharply to 62% by 2030 [11]. Many buildings constructed before the late 1980s were designed without comprehensive seismic considerations, as South Korea's first mandatory seismic design code was only introduced in 1988 [12]. Although modern seismic design regulations are now well established, a substantial portion of the building stock remains vulnerable to seismic and other structural risks. In particular, in Seoul, masonry structures account for approximately 60.3% of buildings over 30 years old, underscoring the urgent need for proactive maintenance and targeted retrofitting strategies to enhance the safety and resilience of aging structures [13]. Among various construction components, the structural performance of masonry buildings is highly dependent on the strength of the mortar joints. Due to the inherently low tensile strength of mortar, masonry structures are significantly more susceptible to seismic forces compared to reinforced concrete (RC) structures [14; 15]. As a result, considerable attention has been directed toward developing effective repair techniques and strengthening materials, aimed at enhancing the earthquake resistance of older masonry buildings [16]. Accordingly, not only is strengthening necessary, but the establishment of an efficient finite element modeling framework for accurately evaluating the structural stability of aged masonry buildings is also critically required. Recent advancements in the retrofitting of masonry structures have emphasized the integration of strengthening and energy efficiency improvements. Various studies have evaluated different retrofitting techniques to improve the structural performance of masonry walls. [PERSON] et al. [17] introduced an integrated seismic and energy retrofitting system utilizing TRM and insulation materials, demonstrating through experimental, analytical, and finite element analysis (FEA) that significant improvements in structural behavior and thermal performance could be achieved. Similarly, [PERSON] et al. [18] evaluated the in-plane mechanical behavior of masonry walls strengthened with TRM and insulation layers, confirming their effectiveness in increasing the structural capacity under seismic loading. [PERSON] [19] applied an open-source FEA platform to simulate masonry elements strengthened with TRM, showing good agreement between numerical predictions and experimental results. In addition, [PERSON] et al. [20] investigated the blast response of masonry walls strengthened with glass-fiber-reinforced polymer (GFRP) sheets. Through experimental studies and FEM simulations using ANSYS-AUTODYN, they demonstrated that GFRP strengthening effectively enhanced the blast resistance of masonry walls by increasing flexural capacity and reducing debris scattering.