Hybrid effect of basalt fiber textile and macro polypropylene fiber on flexural load-bearing capacity and toughness of two-way concrete slabs

This paper presents an experimental study on the two-way concrete slabs with steel-free reinforcements. These include basalt fiber textile, macro polypropylene (PP) fiber and a combination of both. The plain concrete (PC) slab and steel reinforced concrete (RC) slab are studied as references. Furthermore, a comparative analysis on load bearing capacity, toughness and failure pattern of the slabs is performed. The test results indicate that the incorporation of basalt fiber textile and macro PP fibers can significantly improve load bearing capacity and toughness, and there is a positive synergetic effect between basalt fiber textile and macro PP fiber in the hybrid system. Similar to PC slab, the concrete slab reinforced with only 1-layer basalt fiber textile (BTRC1) demonstrates clearly brittle behavior. The addition of macro PP fibers may enhance the load bearing capacity in the post-peak region and convert the brittle failure pattern into a ductile one. In addition, BTRC1 slab with 8 kg/m3 macro PP fibers shows higher flexural capacity than those of RC slab with a steel ratio of 0.31%, and this implies that the combination of basalt fiber textile and macro PP fiber can be used to replace the steel mesh as a new type of durable reinforcement in structural members.National Natural Science Foundation of China (Grant No. 51578109

An overview of chemical additives present in plastics: Migration, release, fate and environmental impact during their use, disposal and recycling

Over the last 60 years plastics production has increased manifold, owing to their inexpensive, multipurpose, durable and lightweight nature. These characteristics have raised the demand for plastic materials that will continue to grow over the coming years. However, with increased plastic materials production, comes increased plastic material wastage creating a number of challenges, as well as opportunities to the waste management industry. The present overview highlights the waste management and pollution challenges, emphasising on the various chemical substances (known as “additives”) contained in all plastic products for enhancing polymer properties and prolonging their life. Despite how useful these additives are in the functionality of polymer products, their potential to contaminate soil, air, water and food is widely documented in literature and described herein. These additives can potentially migrate and undesirably lead to human exposure via e.g. food contact materials, such as packaging. They can, also, be released from plastics during the various recycling and recovery processes and from the products produced from recyclates. Thus, sound recycling has to be performed in such a way as to ensure that emission of substances of high concern and contamination of recycled products is avoided, ensuring environmental and human health protection, at all times