Search

To address the challenges in predicting the aeroelastic phenomenon and the resulting wind-induced forces on slender bridges, a real-time aeroelastic hybrid simulation (RTAHS) system was developed. The RTAHS system directly measures the aerodynamic and aeroelastic forces through load cells. It controls the next step's position of the deck section model with linear motors by solving the governing equations of motion in real time. Given the complex shape of a bridge deck section geometry, load cells are chosen for force measurement instead of as pressure sensors. In the previous RTAHS system proposed by the authors, the inertial forces of a rectangular section model were eliminated from the measured forces under the assumption of the model's rigid-body motion. However, when conducting RTAHS experiments with a realistic bridge deck section model, increasing the mass ratio between the mass of the model and the target mass input to the hybrid system results in unstable vibrations. This instability is primarily attributed to forces generated by the model's flexibility. This study developed an improved RTAHS system, which took into account the inertial forces arising from the nonrigid motion of the flexible bridge deck section model. An accelerometer was additionally installed at the midpoint of the model, and the inertial forces caused by the nonrigid behavior were compensated using a calibration factor derived from impact hammer tests. This approach was validated by comparing the spring-supported experiments conducted on a realistic bridge deck section model. [ABSTRACT FROM AUTHOR]

The prevalent use of unsustainable polymers in current X‐ray scintillators poses a significant environmental concern. The advancement of biodegradable X‐ray scintillators holds promise in mitigating escalating environmental issues tied to electronic or medical waste and carbon footprints. Herein, a biodegradable and flexible X‐ray scintillation film is presented employing lead‐free 0D Cs3Cu2I5 perovskite nanoparticles integrated into densified‐delignified wood (Cs3Cu2I5@D‐Wood). The Cs3Cu2I5@D‐Wood film demonstrates precise and detailed X‐ray imaging capabilities, achieving a high spatial resolution of 10 line pairs per millimeter (lp·mm−1). To minimize the environmental impact associated with disposal, metal and halide ions (e.g., Cs+, Cu+, I−) from Cs3Cu2I5@D‐Wood can be easily retrieved by a simple solvent extraction process. The approach showcases the potential of biodegradable wood‐based X‐ray scintillation screens as alternatives to conventional, plastic‐based screens. This offers a significant contribution to environmental sustainability by reducing electronic or medical waste. [ABSTRACT FROM AUTHOR]