calcium phosphate (Ca3(PO4)2): 1
Life Sciences
Information and Communication
Nanotechnology / Materials
Manufacturing Technology
Human and Social Sciences
Energy
Environment
Tourism / Community development
Arctic Research
Social Infrastructure
Open Facilities
View All
View Detail-
New Ground Injection Material Using Calcium Phosphate
Ground-solidifying calcium phosphate compound, a major component of the teeth and bones of living organisms in nature, is an innovative low environmental impact injection material.
Focusing on calcium phosphate compounds (CPC) as a new cementing material for geotechnical grouting, we have investigated the optimum conditions for the precipitation of CPC and the solidification of sand by CPC, newly discovering two possibilities for their use: chemical grout and biogrout.
Research
To develop a new grout with low environmental load, we focused on minerals produced by living organisms in nature (biominerals), especially CPC, a major component of teeth and bones, and investigated the optimum conditions for CPC precipitation. We also conducted uniaxial compression tests on sand specimens solidified with CPC. In the CPC precipitation test, we have found that the precipitation volume tends to increase as the pH increases from weakly acidic to near neutral. This causes the uniaxial compressive strength of the CPC-solidified sand specimens to reach about 90 kPa, which is within the target range of 50 to 100 kPa for uniaxial compressive strength of sandy soil to prevent liquefaction. Electron microscopy of the specimens showed whisker-like CPC crystals (Fig. 1). These results indicate two possibilities of their usage: chemical grout using self-hardening property and biogrout using pH-dependent precipitation volume.
Satoru Kawasaki Professor
