Study of biochar in cementitious materials for developing green concrete composites

Area of Science:

• Materials Science
• Civil Engineering
• Environmental Science

Background:

• Biochar, a carbon-rich material from waste biomass, offers carbon sequestration potential.
• Traditional concrete production has significant environmental implications.
• Developing sustainable binders for concrete is crucial for green construction.

Purpose of the Study:

• To investigate biochar as a partial cement replacement in concrete without superplasticizers.
• To evaluate the mechanical, volumetric, and durability properties of biochar-based concrete.
• To determine the optimal biochar content for enhanced concrete performance.

Main Methods:

• Concrete mixtures were prepared with 0-5 wt% biochar replacing cement.
• Mechanical strengths (compressive, tensile, flexural) and water absorption were measured.
• Synchrotron-based micro-computed tomography and X-ray diffraction were used for volumetric and microstructural analysis.

Main Results:

• Optimal biochar content (2 wt%) increased compressive strength by 18.95%, tensile strength by 19.64%, and flexural load by 12%.
• Biochar incorporation reduced water absorption, indicating decreased porosity.
• X-ray diffraction confirmed increased calcium-silicate-hydrate formation at optimal biochar levels.

Conclusions:

• Biochar can be effectively used as a partial cement replacement in concrete, enhancing mechanical properties and durability.
• An optimal biochar dosage is critical; higher concentrations negatively impact performance.
• This novel biochar-based concrete offers a sustainable alternative for green construction materials.