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Post-tensioned slab systems serve as an effective method to enhance the progressive collapse resistance of concrete flat plate structures by significantly improving the punching shear and post-punching capacities of their slab-column joints. While the existing research mainly focused on the punching shear behaviour of post-tensioned slab-column joints in small deformation stages, the post-punching behaviour in large deformations has been overlooked. This study aims to fill this research gap thorough experimental and numerical studies. Experimentally, four slab-column joints, including three post-tensioned specimens (with varied prestressing levels) and one specimen without tendons, were designed and tested. Detailed failure process and load-resisting mechanisms of the specimens at different deformation stages were discussed. The test results confirmed the efficiency of post-tensioning in improving the punching shear performance. Varying prestressing levels have influenced the development of punching shear capacity but did not affect the growth rate of load resistance in the initial post-punching stage. Numerically, validated finite element models were used to predict the post-punching capacities of the specimens. The numerical results indicated that post-tensioning helped increase post-punching capacities, but such an enhancement was independent of the prestressing levels. Additionally, the influence of the rupture strains of both tendons and reinforcement on the post-punching capacity was investigated through a parametric study. • Completed failure process and load-bearing mechanisms of post-tensioned flat plate slab-column joint specimens were explored. • The post-tensioning systems in improving the punching shear and post-punching performance was investigated. • High-fidelity 3D FEM models of the post-tensioned flat plate slab-column joints were developed and validated. • The influence of the rupture strains of rebars and tendons on the post-punching capacity was qualified. [ABSTRACT FROM AUTHOR]

• Three flat slab-column joints with drop panels and shear studs were tested considering in-plane restraints. • Pre- and post-punching failure mechanisms were analysed. • Punching shear strength was validated against international codes. To investigate the pre- and post-punching failure performances of flat slab-column joints with drop panels and shear studs, static loading tests were conducted on three joint specimens subjected to in-plane restraints. The pre- and post-punching failure modes and load capacities of the joints were analysed. The tests identified successive punching failures at two critical regions (column perimeter and slab-drop panel interface) in all three joints. Compared with the specimen with a drop panel only, installing shear studs within the drop panels contributed to improving the punching shear strength. Although the post-punching capacity was not significantly improved, utilisation of shear studs effectively increased the ductility of the joints, rendering the punching failure around the column area more ductile. Punching shear strength validation against the international design codes reveals that they were conservative for the specimen with a drop panel only but overestimated for specimens with drop panels and shear studs. [ABSTRACT FROM AUTHOR]

In this work, a capacitive flexible tactile sensor based on the composite dielectric layer with a C-type symmetrical structure is proposed to improve the sensing performance through the introduction of a precise structure. Combined with simulations and experiments, the influence of the structural characteristics of the tactile sensor on its sensitivity is investigated, the correlation between the signal output of the sensor and the loading pressure is shown for different structural parameter designs, and the structure of the sensor is optimized. Data results display that the tactile sensor proposed in this work exhibits a lower detection limit (8.6 Pa) and an ultra-wide linear sensing range (8.6–500 kPa). In addition, from the 55 ms response time of the sensor and 2000 cycles of experiments, it can be concluded that the sensor possesses good repeatability and durability, and can achieve more accurate measurement results in motion detection, soft robots, and electronic skin. [ABSTRACT FROM AUTHOR]

Flexible piezoresistive sensors hold a great potential with broad application spectrum in human-computer interaction and wearable electronic devices. Inspired by human touch sensation architecture, we report a new type of flexible piezoresistive sensor with ultrawide sensing range and highrobustness by engineering biomimetic structure and carbon black (CB)/MXene/SR/fiber nanocomposites. The facile fabrication processes, piezoresistive sensing mechanism, and performance of the device are comprehensively investigated. The sensor provides a high sensitivity of 2.18 kPa−1, ultrawide linear sensing range of 0.1–1700 kPa, fast response time (∼100 ms), and reliable durability (>5000 cycles). Furthermore, the developed flexible devices have been effectively implemented as electronic skin, demonstrating potential functions in manipulator soft grabbing and human movement monitoring. Such architecture paves the way for great application in the fields of healthcare, human–machine interface, and extremely large pressure monitoring. [ABSTRACT FROM AUTHOR]