Development of methodology to evaluate passing ability and test sample preparation for superworkable concrete

Sample rodding was found to enable the reduction of surface honeycombing without affecting mechanical properties or increasing the risk of segregation. The vibration consolidation enhanced mechanical properties and surface quality but led to segregation, unless the concrete was highly stable. Recommendations were made on the adequate consolidation energy on samples and test method devices using both consolidation modes. For example, test samples can be cast in one lift and consolidated with 20 strikes of rodding or vibration for 20 s. The modified L-box with internal consolidation, using a 33-mm pencil vibrator to reach a minimum L-box blocking ratio of 0.80, of 5 and 20 s is recommended for SWC and FR-SWC, respectively. Such concrete should be cast in a single lift and consolidated with 10 internal strikes using a 16-mm steel rod when performing the slump flow, modified J-Ring test, unit weight, and air volume tests.