Current methods to measure tensile strength and toughness in Steel Fiber Reinforced Concrete (SFRC) show a considerable scatter. That scatter makes difficult the quality control, in particular when such properties are taken into account in the evaluation of overall strength of the precast tunnel lining segments, as in the case of the Line 9 of the subway in Barcelona. In order to improve the material assessment procedure, the Double Punch Test (DPT) has been recovered for the quality control of the tension behavior of SFRC. Results of an initial feasibility research are presented, showing a significant reduction of the scatter in the values of the tension strength and in the toughness. Other advantages shown by this test are: (1) the reduced size 150x150 mm of the cylindrical specimens, compared with those used in beam test, and (2) the use of a conventional compression press controlled by displacement.

Peer Reviewed