Structural performance enhancement of concrete beams with steel overlapped splices using nanoparticles

Abstract This paper presents research program towards cleaner building industry; through producing nano-enabled concrete, namely Carbon Nano Tubes (CNTs) Concrete (CNT-CRETE). Structural beam specimens are cast; hence, a series of three-point loading flexure tests is conducted to evaluate and compare the behavior of five groups of standard-size regular reinforced (RC) beams, compared with those using CNT-CRETE. Two previously recommended percentages of CNT are used (0.02% and 0.04% of cement weight). Three possible splice shapes are tested: direct contact splices, and two possible non-contact splices (spacing distances of 1.5 and 3.5 splice bar diameters). The splices with direct contact splices lead to the highest flexural load capacity. On the other hand, non-contact lap splices result in a more flexible section. CNT-CRETE beams exhibited considerable improvement in overall performance. Hence, using CNT-CRETE can lead to future reductions in splice lengths previously recommended by different codes for regular concrete. This will be an innovative addition to different codes. This step requires intensive future studies to cover different CNT types and configurations.