Recent advancements in seismic retrofit strategies have focused on low-impact, rapid, and reversible interventions, with self-centering rocking dual-frame (SCR-DF) systems demonstrating strong potential for enhancing the seismic resilience of reinforced concrete (RC) buildings. These systems, typically integrated as exoskeletons, improve seismic resistance by combining dissipative devices with post-tensioning and column uplift mechanisms to provide self-centering capability, thereby limiting residual deformations and facilitating rapid post-earthquake recovery. This research examines the development and effectiveness of a SCR-DF system applied as an external dissipative exoskeleton to enhance the seismic resilience of a real case study RC building. The expected seismic behavior of the SCR-DF system is validated through simulation results. Equations predicting the load-deformation behavior of the rocking systems are developed, ensuring accurate control of key limit states for reliable performance. Design parameters—such as frame configurations, overturning moment resistance, fuse properties, and post-tensioning stress—are optimized based on the inelastic behavior of the existing structure using a displacement-based design procedure. Nonlinear computational analyses are used to validate these designs. The peak interstory drift ratios (IDR) of the retrofitted building are significantly reduced compared to those of the existing structure, reaching approximately 0.69
Waste tire rubber has been widely investigated as a modifier for concrete and mortar. However, its combined effects on the flowability of fresh grout and the energy dissipation and failure behavior of hardened cement grout containing fine rubber particles remain insufficiently quantified. This study therefore links mixture composition with material performance for cement-based grout containing waste-tire-rubber particles as compliant viscoelastic inclusions. A rubber-modified cement-based grouting material (RMCG) was prepared with surface-treated waste tire rubber particles. Then, orthogonal and single-factor experiments were conducted. These experiments evaluated the effects of water-cement ratio (WCR), rubber content (RC) and rubber particle size (RPS) on fluidity, flexural strength, compressive strength, flexural-compressive ratio, deformation modulus, energy dissipation and failure characteristics. Range analysis generally yielded a relative effect ranking of WCR > RC > RPS. Variance analysis further confirmed that WCR and RC significantly affected most investigated properties, while the effect of RPS was mainly reflected in fluidity. Increasing RC from 0
As materials for impervious facing and core walls, hydraulic basalt fiber–reinforced asphalt concrete (HBFAC) is prone to cracking damage under the combined effects of temperature and creep. To investigate the influence of temperature on the creep performance of HBFAC, this study established a numerical model by integrating basic mechanical tests and uniaxial creep test data, employing the discrete element method (DEM) coupled with a temperature-modified Burgers constitutive model. Subsequently, three-dimensional scanning and cluster generation techniques were used to reconstruct the realistic structure of HBFAC, enabling analysis of the temperature-dependent mesoscopic crenep characteristics and elucidation of the corresponding failure mechanisms. The results indicate that temperature significantly affects the creep behavior of asphalt mixtures. Under a confining pressure of 0.2 MPa, the creep failure rates at 0 °C, 4 °C, and 8 °C increased by 53
To address the performance deterioration of polycarboxylate superplasticizer (PCE) in mud-containing aggregate concrete (10
