Improving the properties of bio-based raw earth building materials using MICP

Climate change is one of the major issues of our time. The residential and tertiary building sector contributes greatly to CO2 emissions. In order to limit these greenhouse gas emissions, the use of bio-based materials seems essential. Raw earth eco-geo-materials represent a promising alternative to reinforced concrete because they are low energy consuming and constitute an abundantly accessible resource. However, the earth being plastic, it tends to crack by shrinkage. Various researches have looked into this problem to find methods to remedy it. One of them is the MICP or Microbially Induced Calcite Precipitation. In this study, we use MICP in clay samples in order to evaluate its proper functioning in this medium. The soil-mixing process allowed us to produce clay samples with and without MICP treatment in order to determine by mechanical tests, their strength increase.