ABSTRACT
This research focuses on the high performance wet-mix sprayed concrete (HPS) with compressive strength of over 95MPa at 28 days, developed as one of the solutions for supportive system in tunnel construction. To the best of our knowledge, this will be the highest achieved compressive strength in such an application once commercialized. To achieve ultra-high strength after application, it is essential to reduce the water to binder ratio (W/B) with enough margin of the final strength after the addition of accelerator. With such low W/B, the fresh concrete is often too viscous to be pumped and sprayed. To resolve this problem, we have developed a new binder material which will allow fresh concrete properties with good workability and ultra-high strength, suited for sprayed concrete. This paper reports the various material properties of HPS and verification results on manufacturing and workability conducted at a tunnel project.
