The main objective of this study was to evaluate the use of enzymatic induced carbonate precipitation (EICP) treatment for erodibility improvement, scour mitigation, and water infiltration capacity of beach sand at one, two, and three cycles of treatment. EICP is a biochemical process that produces calcium carbonate precipitation within a soil matrix to improve the geotechnical properties of the soil. Direct shear test (DST) was used to examine the shear behavior of bio-cemented beach sand after one and two cycle treatment, the results of which showed that the cohesion was increased substantially, especially after the second cycle; conversely, the friction angle was decreased. The mineralogy of treated soil was also assessed using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The mini-jet test has been used to adequately measure the soil erosion characteristics of the biotreated sand (1–3 treatment cycles) in the laboratory, the results of which indicated a significant improvement compared to the control specimen after the third cycle of EICP treatment, with reduced erosion rate and scour depth in the order of approximately 88-fold and 23-fold respectively. After three treatment cycles, the seepage rate was decreased to 71 times lower than the untreated specimens. Strong positive correlations were found between CaCO3, seepage rate, erosion rate, and soil cohesion. The results of this study have confirmed that there is strong evidence for improving erodibility behavior and shear strength of beach sand via EICP treatment. The results of this study would be beneficial to engineers in better understanding bio-cementation techniques and their implementations.
- Beach sand
- Soil improvement
ASJC Scopus subject areas
- Safety, Risk, Reliability and Quality
- Geotechnical Engineering and Engineering Geology
- Computers in Earth Sciences