A new sort of high performance concrete is introduced which combines most advantages
of prestressed concrete and steel fiber concrete, named steel fiber reinforced self-stressing
concrete(SFFRSSC for short). Self-stressing concrete is actually a kind of expansive concrete which
self-stresses, namely pre-compressive stresses, are induced by dint of some restrictions generally
provided by steel bars to concrete expansion after hydration of expansive cement. As a result of
chemical reaction, concrete archived prestresses by itself different from mechanical prestressed
concrete, so called self-stressing concrete. By distributing short-cut steel fibers into self-stressing
concrete at random, prestresses( self-stress) are created in concrete under combined restriction of
steel bars and steel fibers. Thank to the pre-stresses tensile strength of concrete are significantly
increased as well as cracking strength. In addition, expansive deformation of SFFRSSC can
compensate the shrinkage of concrete to decrease shrinkage crack, and the steel fibers play an
important role in post-crack behavior. On the other hand, self-stressing concrete can avoid the
troubles of construction compared with conventional mechanical prestressed concrete. For purpose of
understanding the properties of SFFRSSC, in this paper some researches were carried out to
investigate the special expansive behaviors of restrained expansive deformation with restriction of
steel bar as well as steel fiber. The test results indicated that steel bar and steel fiber both provide
effective restrict to self-stressing concrete as result of forming prestresses in concrete.
OPTIMIZATION OF UHPFRC BEAMS SUBJECTED TO BENDING USING GENETIC ALGORITHMS
