Development of a novel cleaner construction product: Ultra-high performance concrete incorporating lead-zinc tailings

This paper addresses a development for a novel sustainable Ultra-High Performance Concrete (UHPC) incorporating lead-zinc tailings. The modified Andreasen & Andersen particle packing model is utilized to achieve a densely compacted cementitious matrix and the lead-zinc tailings are utilized to replace cement by 10%, 20%, 30% and 40% (wt.), while the packing densities of all the designed UHPC mixtures are almost keep the same. Then, the impact of added lead-zinc tailings on the fresh and hardened behaviors of the developed UHPC is investigated. The obtained experimental results reveal that the workability, compressive strength and chlorine anion penetration resistance of the UHPC decrease with the addition of lead-zinc tailings. However, it is possible to develop self-compacting UHPC with up to 30% replacement of cement by lead-zinc. Moreover, it is noteworthy that the addition of lead-zinc tailings could significantly decrease the early autogenous shrinkage of UHPC, which is beneficial for its microstructure development and application. Additionally, the leaching toxicity of heavy metals for this developed sustainable UHPC is far lower than that of the National Standard of China. The ecological evaluation demonstrates that replacing cement by lead-zinc tailings in the production of UHPC can significantly reduce its environmental impact, which provides a promising view for developing and applying a novel cleaner construction product with advanced properties.