The book presents the work of the RILEM Technical Committee 261-CCF, which organized the challenging International Round Robin Test (RRT) on the creep behaviour of Fibre Reinforce Concrete (FRC) cracked specimens. Although different creep test methodologies have been developed in recent years, the absence of a standardised creep methodology hindered general comparisons. Therefore, the RILEM TC 261-CCF launched an ambitious international RRT program to improve the knowledge on long-term behaviour of cracked sections of FRC and assess all the different testing methodologies, assuming the big variability of testing criteria among the scientific community. The participation of 19 laboratories across 20 institutions in 14 countries all over the world enabled the realisation of the largest experimental campaign on creep in the cracked state. As a result of the RRT, an extensive database of creep test results was created containing comprehensive information from 124 cracked FRC specimens tested using different creep testing procedures in agreed conditions.

The book will benefit academics and practitioners interested in the long-term behaviour of FRC since it served as basis for the recently published RILEM Recommendation on creep testing procedure and represents the current knowledge on creep in cracked FRC specimens.

Aitor Llano-Torre is senior researcher at the Institute of Concrete Science and Technology (ICITECH) of the Universitat Politècnica de València, Spain.

Pedro Serna is professor of construction materials at the Universitat Politècnica de València, Spain.

Introduction and Background.- Round-Robin Test Program and Execution.- Fibre Reinforced Concrete Characterization.- General Procedure of Creep Test.- Equipment and Procedure Description.- Data and Parameter Definition.- Round-Robin Test Results.- Analysis of the RRT Results.- Statements and conclusions.- Appendix A: Specimens Production Index.- Appendix B: Characterization Test.- Appendix C: Database and Parameter Definition.- Appendix D: Creep coefficients results.- Appendix E: Crack opening rate (COR) results.