Parametric and feasibility investigation on drone-assisted placement of self-compacting lightweight concrete

This study investigates the feasibility of drone-assisted concrete placement using self-compacting lightweight concrete (SCLC), with an emphasis on enhancing construction efficiency, safety, and accessibility in challenging environments. The research comprises two main components: (1) the development of an optimized SCLC mix suitable for aerial placement, and (2) a parametric evaluation of drone performance in transporting and pouring concrete under varying operational conditions. The optimized SCLC mix, containing 400 kg/m³ of cement and 8% superplasticizer, achieved a slump flow of 660 mm, T50 time of 4.8 seconds, and compressive strength of 26.8 MPa, satisfying EFNARC criteria. Drone-based experiments assessed flight energy, pouring time, and mechanical properties across multiple payloads, flowabilities, drop heights, and wind speeds. Results indicate that flying energy increases by 17.4% per kilogram of payload, while unit energy for concrete pouring is estimated at 1.775 Wh/kg. Concrete flowability significantly affects pouring time, with improved flow reducing energy and time consumption. Additionally, higher drop heights and wind speeds were found to increase splash dispersion, affecting placement precision. Mechanical testing revealed a slight reduction in compressive and flexural strengths for drone-cast specimens—6.6% and 12.2% lower, respectively—compared to conventional casting, highlighting minor challenges in precision placement. Despite these limitations, the findings confirm the technical feasibility of drone-assisted SCLC placement at laboratory scale and identify key operational parameters influencing performance. This study contributes to the emerging field of aerial robotics in construction, offering a foundation for future development of automated, drone-based concrete placement in remote or hazardous environments.