Improved strength and durability of concrete through metabolic activity of ureolytic bacteria

publicaciones

Maria Jose Castro Alonso1, Carlos Eloir Lopez Ortiz1, Sixto Omar Garcia Perez2, Rajeswari Narayanasamy2, Gerardo del Jesús Fajardo San Miguel3, Héctor Herrera Hernández4 & Nagamani Balagurusamy1*

1Laboratorio de Biorremediación, Facultad de Ciencias Biológicas, Universidad Autónoma de Coahuila, Carretera Torreón-Matamoros Km 7.5, Torreón, Mexico

2Facultad de Ingeniería, Ciencias y Arquitectura de la Universidad Juárez del Estado de Durango, Gómez Palacio, Mexico

3Facultad de Ingeniería Civil, Universidad Autónoma de Nuevo León, Av. Universidad S/N, Ciudad Universitaria, CP 66451 San Nicolás de los Garza, Nuevo León, Mexico

4 Centro Universitario, Universidad Autónoma del Estado de México,San Javier Atizapán de Zaragoza, Mexico

*bnagamani@uadec.edu.mx

In recent years, biomineralization process is being employed in development of bioconcrete, which is emerging as a sustainable method to enhance the durability of concrete by way of increasing compressive strength and reducing the chloride permeability. In this study, different bacterial strains isolated from the soils of the Laguna Region of Mexico were selected for further study. ACRN5 strain demonstrated higher urease activity than other strains, and the optimum substrate concentration, pH, and temperature were 120 mM, pH 8, and 25 °C, respectively. Further, Km and Vmax of urease activity of ACRN5 were 21.38 mM and 0.212 mM min1, respectively. It was observed that addition of ACRN5 at 105 cells ml1 to cement-water mixture significantly increased (14.94%) in compressive strength after 36 days of curing and reduced chloride penetration. Deposition of calcite in bio-mortars was observed in scanning electron microscopy and energy dispersive X-ray diffraction spectrometry analyses. Results of this study demonstrated the role of microbially induced calcium carbonate precipitation in improving the physicomechanical properties of bio-mortars.

bionconcrete-strength-durability

 


COMPARTE