Combination of Enzyme-Induced Calcium Carbonate Precipitation (EICP) and Macro-Synthetic Fibers for Soil Improvement: Fid-Bau Portal

Combination of Enzyme-Induced Calcium Carbonate Precipitation (EICP) and Macro-Synthetic Fibers for Soil Improvement

Alotaibi, Emran / Arab, Mohamed G. / Omar, Maher

This study investigates the feasibility of using macro-synthetic fiber to improve the mechanical properties of Enzyme Induced Carbonate Precipitation (EICP) treated soils. The fiber used in this study is macro-synthetic composed of polypropylene and polyethylene. Unconfined compressive strength (UCS) test was used to investigate the effect of incorporating the fibers into the EICP-sand matrix. The effect of fibers on stress–strain behavior, peak and residual compressive strength, secant modulus of elasticity, energy absorption, and calcium carbonate distribution was evaluated. Three levels of fiber were used in the study: 0.1%, 0.3%, and 0.5% (by weight of the dry soil). Generally, the results have shown an increase in EICP-treated soil residual compressive strength and strain at failure by adding fiber to the EICP-treated soils. The increase in the macro-synthetic content has initially slightly decreased the EICP treated soil UCS followed by an increase in UCS at the fiber content of 0.5%. The UCS of soil treated with both EICP and fiber has reached a UCS of 274.1 kPa with an 87.5% increase compared to soil treated with EICP alone. This improvement is accompanied by more ductile behavior with an increase by 54.3 kPa in residual compressive strength compared to zero in the case of EICP alone.