Effect of Casting Position on Mechanical Performance of Ultra-High Performance Concrete

The mechanical performance of ultra-high performance concrete (UHPC) is a function of fiber distribution and orientation, which are affected by the processing of the fresh material. In this study, the influences of two casting positions (mid-cast and end-cast) on strength and fracture properties of UHPCs with different fiber types and fiber contents were investigated. The results show that mid-cast specimens have higher flexural strength and fracture properties than end-cast specimens, while the compressive strength is almost unaffected by casting position. Compared to specimens with straight fibers, the flexural strength of specimens with hooked-end fibers is more likely to be affected by casting position. The residual load-to-peak load ratio is independent of casting position but affected by fiber type and fiber content.

Automated summary

This study investigates the influence of different casting positions on the strength and fracture properties of ultra-high performance concrete, showing that mid-cast specimens have higher flexural strength and fracture properties compared to end-cast specimens. The flexural strength of specimens with hooked-end fibers is more likely to be affected by casting position. The residual load-to-peak load ratio is independent of casting position but affected by fiber type and fiber content.