Vivek A Neha, Kumar P Prasanna, Reddy Divijendranatha
Department of Civil Engineering, B.M.S. College of Engineering, Bengaluru, India.
Department of Biotechnology, B.M.S. College of Engineering, Bengaluru, India.
Heliyon. 2025 Feb 13;11(4):e42680. doi: 10.1016/j.heliyon.2025.e42680. eCollection 2025 Feb 28.
Rammed Earth (RE) is finding more applications as a sustainable construction material with cement as stabilizer. However, RE is susceptible to water absorption through pores, weakening the bond between the soil particles, reducing its strength and lifespan. Increased cement content, though enhances strength, does not effectively fill pores. There are no proven methods to fill pores with cementitious materials in structures like RE. In this study, Microbially Induced Calcium Carbonate Precipitation (MICP) has been adopted during casting to improve the compressive strength of cement-stabilized RE. MICP technique not only enhances the strength but also fills pores, inhibiting capillary water absorption thereby extending the lifespan of RE. The results of tests on MICP-induced specimen indicated that the compressive strength increased by an average of 26 %. The capillary water absorption reduced considerably with the bacterial induction. A relationship between compressive strength and capillary water absorption of RE is arrived. While further study is necessary for microbial stabilization to be used in RE, these preliminary data show promising results.
夯实土（RE）作为一种以水泥为稳定剂的可持续建筑材料，正得到越来越广泛的应用。然而，夯实土易通过孔隙吸水，削弱土壤颗粒之间的粘结力，降低其强度和使用寿命。增加水泥含量虽然能提高强度，但并不能有效填充孔隙。在夯实土等结构中，尚无经证实的用胶凝材料填充孔隙的方法。在本研究中，在浇筑过程中采用了微生物诱导碳酸钙沉淀（MICP）来提高水泥稳定夯实土的抗压强度。MICP技术不仅能提高强度，还能填充孔隙，抑制毛细吸水，从而延长夯实土的使用寿命。对MICP诱导试件的测试结果表明，抗压强度平均提高了26%。细菌诱导使毛细吸水率大幅降低。得出了夯实土抗压强度与毛细吸水率之间的关系。虽然微生物稳定化在夯实土中的应用还需要进一步研究，但这些初步数据显示出了有前景的结果。
