PMID- 29416093
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20191120
IS  - 2045-2322 (Electronic)
IS  - 2045-2322 (Linking)
VI  - 8
IP  - 1
DP  - 2018 Feb 7
TI  - Fly ash incorporated with biocement to improve strength of expansive soil.
PG  - 2565
LID - 10.1038/s41598-018-20921-0 [doi]
LID - 2565
AB  - Microbially induced calcium carbonate precipitation (MICP) results in the 
      formation of biocement (BC). This process, also known as biocementation, is 
      recently widely used to improve the strength and durability of building materials 
      including soils. In the present study, effectiveness of biocement as admixture 
      with fly ash (FA) was investigated as first few studies to improve geotechnical 
      properties of expansive soils. Biocement precipitated by Bacillus megaterium was 
      blend with four formulations of fly ash at concentrations of 0, 10, 25 and 50%, 
      namely 0% FABC, 10% FABC, 25% FABC, and 50% FABC, respectively. These 
      formulations were separately added to expansive soils. Specimens with 25% FABC 
      resulted in significant improvement in unconfined compressive strength of 
      expansive soil that was more than two-times higher than control. Further, 
      scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), 
      Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) 
      analyses characterized microstructures of soil specimens, and depicted the 
      process of MICP in improving strength of expansive soils. This research indicates 
      that incorporation of biocement in fly ash is an effective means of increasing 
      the strength of expansive soils.
FAU - Li, Mengmeng
AU  - Li M
AD  - Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration (SHUES), 
      School of Ecological and Environmental Sciences, East China Normal University, 
      Shanghai, 200241, China.
FAU - Fang, Chaolin
AU  - Fang C
AD  - Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration (SHUES), 
      School of Ecological and Environmental Sciences, East China Normal University, 
      Shanghai, 200241, China.
FAU - Kawasaki, Satoru
AU  - Kawasaki S
AD  - Faculty of Engineering, Hokkaido University, Sapporo, 0608628, Japan.
FAU - Achal, Varenyam
AU  - Achal V
AD  - Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration (SHUES), 
      School of Ecological and Environmental Sciences, East China Normal University, 
      Shanghai, 200241, China. varenyam@re.ecnu.edu.cn.
AD  - Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 
      200092, China. varenyam@re.ecnu.edu.cn.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20180207
PL  - England
TA  - Sci Rep
JT  - Scientific reports
JID - 101563288
PMC - PMC5803229
COIS- The authors declare that they have no competing interests.
EDAT- 2018/02/09 06:00
MHDA- 2018/02/09 06:01
PMCR- 2018/02/07
CRDT- 2018/02/09 06:00
PHST- 2017/12/04 00:00 [received]
PHST- 2018/01/23 00:00 [accepted]
PHST- 2018/02/09 06:00 [entrez]
PHST- 2018/02/09 06:00 [pubmed]
PHST- 2018/02/09 06:01 [medline]
PHST- 2018/02/07 00:00 [pmc-release]
AID - 10.1038/s41598-018-20921-0 [pii]
AID - 20921 [pii]
AID - 10.1038/s41598-018-20921-0 [doi]
PST - epublish
SO  - Sci Rep. 2018 Feb 7;8(1):2565. doi: 10.1038/s41598-018-20921-0.