IMPACT DYNAMIC PROPERTIES OF MAGNESIUM OXYCHLORIDE-DOPED PAPER SLUDGE COMPOSITES

To address the heavy pollution caused by paper sludge, this study investigates a novel approach by incorporating paper sludge into magnesium oxychloride cement to develop a new type of concrete composite material. To achieve waste utilisation, cost savings and pollution reduction, the impact dynamics properties of the concrete specimens were conducted using an electromagnetically driven Hopkinson pressure bar, while a high-speed camera recorded the specimen destruction process, stress-strain curve, destruction morphology, deformation field, and evolution of energy consumption. Results show that as the paper sludge doping increases, the peak stress of the stress-strain curve and the energy consumption gradually increase. Increasing the voltage leads to a gradual rise in peak stress and energy consumption of the specimen. During the impact test, the transverse fissures gradually are developed in the test block, and as the impact stress increases, the fissures are widened until the specimen eventually being fractured. Moreover, the higher impact voltage and paper sludge content result in the increased specimen displacement and strain. It is expected that nearly 50% of paper sludge will be recycled every year by this method, which will save 10%-20% of raw materials. The conclusions obtained in this study provide a reference for the engineering application of the paper sludge concrete composites. Keywords: Paper sludge, Magnesium oxychloride, Digital image correlation, Energy consumption, Impact dynamic properties.