Structural curved metal dampers are implemented in various applications to mitigate the damages at a specific area efficiently. A stable and saturated hysteretic behavior for the in-plane direction is dependent on the shape of a curved-shaped damper. However, it has been experimentally shown that the hysteretic behavior in the conventional curved-shaped damper is unstable, mainly as a result of bi-directional deformations. Therefore, it is necessary to conduct shape optimization for curved dampers to enhance their hysteretic behavior and energy dissipation capability. In this study, the finite element (FE) model built in ABAQUS, is utilized to obtain optimal shape for the curved-shaped damper. The effectiveness of the model is checked by comparisons of the FE model and experimental results. The parameters for the optimization include the curved length and shape of the damper, and the improved approach is conducted by investigating the curved sections. In addition, the design parameters are represented by B-spline curves (to ensure enhanced system performance), regression analysis is implemented to derive optimization formulations considering energy dissipation, constitutive material model, and cumulative plastic strain. Results determine that the energy dissipation capacity of the curved steel damper could be improved by 32% using shape optimization techniques compared to the conventional dampers. Ultimately, the study proposes simple optimal shapes for further implementations in practical designs.

Globally, as human population and industries grow, so does the creation of agricultural, industrial, and demolition waste. When these wastes are not properly recycled, reused, or disposed of, they pose a threat to the environment. The importance of this study lies in the beneficial use of coconut fibre and mineral wool in the form of fibres in cement mortar production. This study examines the use of coconut and mineral wool fibres in the production of fibre-reinforced mortar. Five different mortar mixtures were prepared, having one control mortar along with four fibre-reinforced mortars. The control mortar is denoted as CM while 1% and 1.5% of mineral wool are incorporated into this mortar mix and denoted as RMM-1.0 and RMM-1.5, respectively. Additionally, the mortar sample configurations contain 1% and 1.5% coconut fibers, designated as RCM-1.0 and RCM-1.5. These samples were subjected to different strength and durability tests to determine their suitability for use in mortar production. The testing findings show that mortar containing 1.5% mineral wool has better compared flexural strength and durability properties. The investigation results will form part of the database for the efficient utilization of natural and waste fibres in the construction and building sectors.

In this study, new steel material classes were added to the OpenSees 3.0.0 library to model their behavior within cold-formed profiles under high temperatures. The new material classes that were added are capable of modeling G-450 and G-550 grade galvanized steels under mechanical and thermal loads. Gypsum panel, a nonstructural material within walls, significantly contributed to the lateral resistance of cold-formed structures. For the first time, the relevant material class was added to OpenSees. First, heat transfer analysis was performed to determine the temperature distribution within different parts of the frame structure. Second, the structure was analyzed under gravity loads, followed by thermal loads. Results from the first step were applied to the structure, and a transient thermomechanical analysis was performed. The output of this analysis included the deformation and force of the members of the structure. The behavior of each new material class was compared with the experimental results to determine the accuracy of the developed OpenSees scripts. Moreover, the results related to modeling with this material class were compared with those of the material classes available in OpenSees. The results exhibited high accuracy with the new material class, and the difference in the results obtained with the current material classes in OpenSees was significant.