Enzyme-Induced Carbonate Precipitation for the Protection of Earthen Dikes and Embankments Under Sur

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Earthen structures such as shore protection dikes and river embankments easily suffer from erosion under surface water runoff. This study made experimental efforts to explore the enzyme-induced carbonate precipitation (EICP) method for slope erosion control under surface runoff for earthen structures. The sandy soils were treated by the EICP method for various rounds. Surface characteristics were evaluated by the surface penetration resistance, calcium carbonate content, and surface hard crust thickness of EICP-treated soils. Slope runoff erosion experiments were carried out to evaluate the erosion control performances of the EICP treatment. The surface penetration resistance, calcium carbonate content, and surface hard crust thickness were found to significantly increase with the treatment rounds. In the erosion experiments, it was observed that the level of damages decreased and the water flow volume required to trigger the damage increased with more treatments. The increase in the soil slope angle led to more serious surface damages. The amount and rate that the soil particles were eroded from the slope surfaces declined with more EICP treatments, which was consistent with those of visual observations. The preliminary investigations presented in this study have shown the poten-tial of the EICP method for slope erosion control under surface runoff for earthen structures.
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