Experimental and numerical investigation of the splice length requirement in high volume fly ash-self compacting concrete (HVFA-SCC) beam

Experimental and numerical investigation of the splice length requirement in high volume fly ash-self compacting concrete (HVFA-SCC) beam

This paper aims to determine the required lap splice length of tensile reinforcement embedded in high volume fly ash-self compacting concrete (HVFA-SCC) beams. The lap splice length is governed by the bond strength of the concrete to the reinforcement. Several studies have shown that the bond strength of HVFA-SCC is greater than that of normal concrete (NC). The difference in the bond strength value will affect the lap splice length requirement. In this research, an experimental investigation was carried out on eight beams with dimensions of 150×250 mm and a length of 2 m under four points of loading. The beams were designed with various lap splices, i.e., 25%, 50% and 75% of the expected lap splice length. Other beams without lap splice were prepared as a control. A numerical study using ATENA Engineering software was also conducted to extend the investigation covering a longer lap splice length. The analysis results show that a lap splice length of 28.8 dB produces a flexural capacity equivalent to the control beam, and the tensile reinforcement has reached its yield state. This lap splice length is lower than expected in NC, suggesting that an efficient tensile reinforcement lap splice can be projected in HVFA-SCC beams.