Development of Innovative Bio-beam Using Microbial Induced Calcite Precipitation Technology
As a new environmental friendly and sustainable technique for soil improvement, microbial induced calcite precipitation (MICP) has been studied widely. Most of previous studies focus on soil modification. This study is to develop innovative bio-beams based on MICP technology. A modified permeable rigid mold has been developed to prepare the bio-beams specimens within the immersing method. The permeable mold provides supports for the bacteria to grow through fully contact cementation media and induce the calcium carbonate precipitated homogeneously within the pores of the sand to form the bio-beam. Bending tests have been conducted to evaluate the flexure behavior of MICP-treated bio-beams. Single and multiple treatment of MICP in the various cementation media concentrations have been conducted. Experimental results show that the vertical load of the MICP-treated bio-beams could reach to 1412 N when the bio-beams were treated for one time. The double treatments of the bio-beams increased to the 163% of bending strength of single-treatment. The peak bending strength of the triple MICP-treated bio-beam specimen increased to 200% of bending strength of single-treatment. The bending strength also increased with cementation media concentrations.
KeywordsBio-beam Microbial induced calcite precipitation Immersing method Bending strength
This paper is based upon work supported by the National Science Foundation Grant No. 1531382 and U.S. Department of Transportation Grant No. (DTRT13-G-UTC50FHWA) through Maritime Transportation Research and Education Center. The first author acknowledges financial support from the China Scholarship Council under Grant No. 201408505113, from Chongqing Research Program of Basic Research and Frontier Technology No. cstc2014jcyjA30005, from Chongqing University of Science and Technology, No. CK2015Z27 and Chongqing BaYu Plan.
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