Recommendation of RILEM TC 261-CCF: test method to determine the flexural creep of fibre reinforced concrete in the cracked state

To date there is no clear consensus about how creep of cracked FRC structural elements should be considered. In recent years, different methodologies have been developed for multiple stress cases. The absence of a standardised methodology to evaluate flexural creep in the cracked state has hindered general comparisons and conclusions that could lead to significant advances in this topic. Since 2014, the study of the creep behaviour of cracked FRC has been coordinated by the RILEM TC 261-CCF. All the available creep methodologies were analysed in terms of procedure, equipment and results. A comprehensive Round-Robin Test (RRT) on the creep behaviour of cracked sections of FRC was proposed and undertaken by a total of 19 participant laboratories from 14 countries all over the world. The analysis and conclusions of the RRT results and the different methodologies provided the basis for this recommendation. This recommendation focuses on the test method to evaluate the flexural creep of FRC specimens in the cracked state. Guidelines on specimen production, detailed test equipment, experimental setup and test procedure as well as the definitions of the most relevant parameters are provided.

Automated summary

There is currently no clear consensus on how to consider creep of cracked FRC structural elements, and the lack of a standardized methodology has hindered general comparisons. Recent studies have focused on different methodologies for multiple stress cases, including a comprehensive Round-Robin Test, providing a basis for significant advancements in this field.