The compressive strength increases at 5% of biochar replacement rate is due to the high-water
absorption capacity of biochar compared to other materials in the mix. This helps to keep the moisture content internally,
which supports the strength development [33,37]. Higher percentage of biochar replacement reduced the cement content,
thus less cement and internal moisture in the biochar induced low workability and compaction difficulty. This was the
reason for the strength reduction observed in the sample with 10 % and 20 % rate biochar. However, biochar could be used as
an effective substitute for cement up to 5% to improve the compressive strength and reduce carbon intensiveness of concrete
or mortar.
Quelle: https://www.sciencedirect.com/science/article/pii/S2214509521000553
