Open AccessImprovement Properties of Self -Healing Concrete by Using Bacteria
Author(s) -
Zainab Hussein,
Abdulhaq Hadi Abedali,
A. S. Ahmead
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/584/1/012034
Subject(s) - compressive strength , absorption of water , materials science , composite material , calcium carbonate , calcite , scanning electron microscope , precipitation , cement , chemistry , mineralogy , physics , meteorology
The aim of this investigation, self-healing of cracks in concrete by using named Bacillus Subtilis bacteria isolated from agricultural soils and dry soil. Four concrete mixes include, one plain mix without bacteria, other mixes containing a different concentrations of bacteria 10 3 , 10 6 and 10 9 cell/ml respectively were prepared. Hardened properties of concrete water absorption, ultrasonic plus velocity, and compressive strength at 7, 28, 60 and 90 days. Also concrete specimens applied to load 10% of compressive strength at 28 days were studied. The result indicate there is decrease in water absorption of (15-38)%, as well as the decrease in the concrete specimens of loading 10% of compressive strength of (23- 41%) relative to control concrete. Increase in compressive resistance of concretes specimens of (6- 20)%, (6-17)%, (8-22)% and (7-20)% for ages 7, 28, 60 and 90 days respectively, concrete specimens loaded by 10% of compressive strength, increased by (25-34%) and (34-39%) for 60 and 90 days relative to control concrete . It was observed that the UPV test of concrete specimens was increased. Scanning Electron Micrographic gave an increased in density, deposition of calcite carbonates in the voids and closure of the crack by precipitation of calcium carbonate layers was observed.