Tensile creep of macro-synthetic fibre reinforced concrete (MSFRC) under uni-axial tensile loading

The increased energy absorption capacity of fibre reinforced concrete (FRC) is well known. Much, however, remains unknown about the time-dependent behaviour of FRC under sustained loading let alone the mechanism causing the phenomenon. This paper reports a study of the time-dependent behaviour of pre-cracked macro-synthetic fibre reinforced concrete (MSFRC) subjected to uni-axial tensile sustained loading. To fully understand the creep behaviour, investigation of the time-dependent fibre pull-out and fibre creep was also conducted. For the purpose of in-service simulation, the MSFRC specimens were pre-cracked before testing. Stress levels investigated were 30-70% of the residual, post crack, uni-axial tensile strength of the MSFRC. The experimental investigations revealed that cracked MSFRC shows significant creep and the fibre creep and the time-dependent fibre pull-out are the major sources of the creep behaviour.