CREEP OF CRACKED POLYMER FIBER REINFORCED CONCRETE UNDER SUSTAINED TENSILE LOADING

In fiber reinforced concrete (FRC), fibers are added to the fresh concrete mix in order to improve the residual tensile strength, the toughness and/or durability of a concrete element. Cur- rently, structural applications remain relatively scarce as the time-dependent behavior of FRC is still poorly understood. This paper reports the first results of an experimental campaign regarding the creep of cracked polymer FRC. In the test setup, cylindrical, notched FRC specimens are considered. The concrete is reinforced with structural polymeric fibers for use in load-bearing applications. In a first step, the material is characterized according to the European Standard EN14651. Secondly, the samples are precracked to localize the creep deformations and to monitor the crack growth in time. The samples are subjected to a sustained tensile load, whereby different load levels with respect to the individual residual strength are considered. The results of the first months of creep loading will be detailed and discussed in the paper