Project Information
Link to Latest Report: Final Report
Background:
The motivation for this project is a recognition of the need for concrete materials that (1) enable accelerated ready-mixed construction methods and (2) have improved durability for lower repair and rehabilitation costs over the life of the bridge. Among recent trends in high-performance, innovative construction materials, the incorporation of low dosages of biochar stands out as a potential means to meet these needs for accelerated bridge construction.
Objective:
The primary objective of this research project is to determine the early-age structure-processing-property relationships of concrete containing moderate replacements of biochar. Quantifying these relationships will enable biochar-infused concrete to be used reliably and at higher volume fractions of replacement for portland cement. Within that objective, our specific goal in this project is to map the relationships among biochar dosage and properties (ash content, fineness, and porosity) to fresh flow properties (yield stress, shear-dependent viscosity, and thixotropy) and early-age mechanical properties and microstructure.
Scope:
The proposed project includes several tasks
- Task 1 – Screen and characterize biochar sources
Use multiple complementary characterization methods to determine the properties of as-received biochars. - Task 2 – Map the rheological properties of pastes and mortar
Rotational rheometry will be used to determine the influence of biochar type and dosage on flow curves and yield stress, using a design-of-experiments approach with biochar dosage, water-solids mass ratio, and superplasticizer dosage as factors. - Task 3 – Determine biochar influence on early-age hydration, carbonation, and mechanical
properties.
Isothermal calorimetry will be used to track real-time hydration rates. Microthermogravimetry will be used to quantify the extent of carbonate mineralization up to seven days of exposure, and mortar cube compressive strength measurements (ASTM C109) will be used to characterize the mechanical integrity of the materials. - Task 4 – Final Report.
A final report will be prepared meeting the RITA requirements for UTC funded projects. The content of the report will contain a detailed summary of the results from the preceding tasks and a recommendation for future phases of the project, if necessary.
Research Team:
Principal Investigator: Jeffrey W. Bullard, Ph.D.
Co-Principal Investigator: Yong-Rak Kim.
Previous Progress Reports :