Statistical analysis of stone mastic asphalt containing steel fiber

The use of various fibers in asphalt mixes has been developed and applied to enhance pavement performance. The conventional asphalt mixture can be improved by including steel fibre as an additive in the asphalt mixture. However, the use of steel fibre in SMA mixtures was not widely studied. Consequently, the objective of this study was to evaluate the effect of steel fibre on the volumetric properties and characterize the performance of steel fibre in SMA mixture. Different steel fiber proportions of 0%, 0.3%, 0.5%, and 0.7% by the total weight of the mixture were used in this study. The test conducted includes the Marshall stability and Flow test, and the Resilient Modulus Test. Response Surface Methodology (RSM) from Design Expert Software was then performed to determine the most optimum properties from the experimental data. The test results revealed that adding steel fiber greatly improved the SMA mixture's resistance to deformation while also increasing its stability, reducing the abrasion loss, and increasing the stiffness of the SMA mixture. Optimized performance was observed at 0.3% steel fiber content and 1598 MPa of resilient modulus. The relative error results show acceptable agreement between the prediction and the experiment which is considered tolerable and acceptable. This demonstrates that the software optimization of the specific SMA with steel fiber characteristics by the RSM technique has the desired precision for laboratory tests.