TY - JOUR ID - 2711 TI - Bio-stabilization of Sand by Surface Percolation JO - Amirkabir Journal of Civil Engineering JA - CEEJ LA - en SN - 2588-297X AU - Karimian, A. AU - Hassanlourad, M. AU - Karimi, Gh. AD - Department of Civil Engineering, Imam Khomeini International University, Qazvin, Iran Y1 - 2018 PY - 2018 VL - 50 IS - 4 SP - 735 EP - 746 KW - Soil Stabilization KW - Bio-Cementation KW - microorganism KW - calcium carbonate precipitation KW - surface percolation DO - 10.22060/ceej.2017.13078.5324 N2 - Most traditional soil improvement methods are time consuming, expensive, require heavy machinery and are environmentally detrimental. As a more environmentally favorable ground improvement method, the bio-cementation of soil offers an alternative to traditional soil improvement techniques. This method is based on microbial precipitation of calcium carbonate. The role of bacteria is producing urease enzyme to catalyzing the hydrolysis of urea. In the presence of calcium ions, the produced carbonate ions in hydrolysis of urea react with the calcium ions and calcium carbonate sediment is formed. This paper investigates the applicability of the bio-remediation of dry loose sand by surface percolation. To evaluate the success of treatment, a series of laboratory experiments was conducted, including, shear wave velocity, unconfined compressive strength, Brazilian tensile strength, calcium carbonate content and etc. The study revealed that the bio-remediation technique causes the improvement of soil strength as a result of the cementation of sand particles. Furthermore, the surface percolation method has the potential of cementation and stabilization of loose sand with desirable depth. Increase in soil strength and calcium carbonate content decreases with increase of depth. Results also showed that increase of strength due to bio-improvement depends to calcium carbonate content, its spatial distribution in pores and particle-to-particle binding numbers. UR - https://ceej.aut.ac.ir/article_2711.html L1 - https://ceej.aut.ac.ir/article_2711_618e54f626f991b4193a34bfc878eb08.pdf ER -