In the present research, multiple UHSC mixtures with locally available foundry sand were produced and analyzed for their hydration and alkali silica reactivity.
UHSC, like conventional concrete, can have a broad range of designs.
Additionally, a densified silica fume was used at a 25% replacement by mass of cement in order to produce the UHSC requirements ([greater than or equal to] 70 MPa [10ksi]) .
A reactive (siliceous) and a nonreactive (manufactured limestone) fine aggregate were used as a part of this study to produce two separate control UHSC mixtures.
This means that concrete below 10,000 psi (70 MPa) is NSC and above 14,500 psi (100MPa) is UHSC. S K Al-Oraimi et al states that "in seventies 6000 psi (42 MPa) concrete was considered high strength and recently 8700 psi (60 MPa) is the lower boundary for high strength concrete".
Less than 6000 psi(42MPa) is NSC(Normal Strength Concrete), 6000-12,800 psi(42-90MPa) HSC (High Strength Concrete) and above this level is UHSC (Ultra High Strength Concrete).
Moreover, existing studies have mainly evaluated the shrinkage behavior of NSC and HSC, and there is little research on UHSC [5, 8, 10].
Therefore, in this study, the shrinkage and cracking behavior were evaluated through unrestrained and restrained shrinkage experiments of HSC, VHSC (very-high-strength concrete), and UHSC with water-to-binder ratios (W/B) of 30%, 25%, and 16%, respectively .
In this study, free shrinkage behavior and restrained shrinkage cracking behavior of concrete of three strength levels and the effect of fly ash on shrinkage behavior of UHSC were investigated experimentally.
The tests by Tan and Pu  show that compared with the ordinary CFST, the strength and plastic deformation of UHSC will be significantly improved due to the confinement effect of steel tube, the same as the bearing capacity of UHSCFST.
The steel tube in rigid skeleton filled with UHSC of strength grade up to C100 and a self-compacting concrete of C50 was used in reinforced concrete arch.
Therefore, effective measures should be taken to improve the brittleness of UHSC so as to ensure its safe application in civil engineering.