## 2 Geometrical and Mechanical Characteristics of the Specimens--Materials
The placement of the longitudinal C-FRP ropes in the grooves along the height of the column is presented in Figure 4a, whereas the application of the C-FRP ropes as external shear reinforcement in X-formed grooves at the two sides of the joint panel is presented in Figure 4b. Supplementary compression tests of concrete were conducted for the evaluation of the concrete strength. The mean value of the compressive concrete strength was almost 34 MPa, whereas the tensile strength of the steel reinforcement was 550 MPa. The modulus of elasticity and tensile strength of the used C-FRP fibers of the applied ropes, as specified by the manufacturer, were 240 GPa and 4 GPa, respectively. Carbon Fiber-Reinforced Polymers (C-FRPs) ropes and sheets tend to have a higher initial material cost per unit compared to traditional construction materials like concrete and reinforcing steel bars. However, the installation procedure for C-FRP ropes is faster and less labor-intensive than traditional methods; it is stressed that they are lightweight and easy to handle and to apply, while fewer workers and lighter equipment are required,  
Figure 4: Application of the C-FRP ropes on the specimen JC0V2X2c. The ropes are placed deep in U-shaped notches. The incision of the notches takes place at the design positions of the C-FRP ropes. (**a**) Application of the longitudinal C-FRP ropes as external flexural reinforcement of the column and (**b**) application of the C-FRP ropes as external stirrups diagonally placed for the shear strengthening of the joint body of the specimen. leading to lower labor costs. A major advantage of the C-FRP ropes is the substantial reduction in construction time and the speed and ease of their application, especially in difficult or confined areas, minimize downtime and disruption, which can translate to significant cost savings in projects where time is critical. Further, C-FRP materials are durable and more resistant to corrosion, reducing long-term maintenance costs. On the other hand, it is widely accepted that concrete is relatively inexpensive as a material, making concrete jacketing a lower-cost option in terms of raw materials. However, significant quantities of concrete and additional reinforcing bars are required to provide sufficient structural strengthening. The installation process for concrete jacketing is labor-intensive, time-consuming, and concrete jacketing often involves significant disruption to the existing structure. Thus, the character of this structural intervention can increase project downtime, especially in occupied buildings. Further, concrete is susceptible to cracking, spalling, and corrosion of embedded steel, especially in aggressive environments, and over time, the maintenance costs for concrete jackets can be substantial. Steel is moderately priced and more expensive than concrete; it requires specialized labor, heavy lifting equipment, and precise installation techniques. The labor-intensive nature of the work can drive up costs significantly. Installing steel jackets usually involves welding and bolting, which can be time-consuming and disruptive to the existing structure. Steel is highly susceptible to corrosion, especially in moist or salty environments, and, obviously, the necessary maintenance to prevent rust increases the long-term costs. In general, although the upfront costs of C-FRP ropes are higher, the overall life cycle cost including installation, long-term maintenance and durability may be proved to be lower than traditional methods, especially for projects requiring fast execution and high-performance standards. While the study focuses primarily on short term effectiveness during seismic excitations, the importance of aging, durability, and environmental impact are also stressed. Previous research has demonstrated that the C-FRP materials exhibit excellent long-term durability due to their resistance to corrosion and chemical attacks.