The fractal characteristics of C80 high performance concrete pore structure subject to high temperatures

• Published in: IOP conference series. Earth and environmental science Vol. 510; no. 5; pp. 52016 - 52026
• Main Authors: Fan, Y N, Du, H X, Shi, L N
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.06.2020
• Subjects: Deterioration; Fractal geometry; Fractals; Growth rate; High temperature; Mercury; Polypropylene; Pore size; Porosity
• ISSN: 1755-1307; 1755-1315
• DOI: 10.1088/1755-1315/510/5/052016

The pore structure of C80 high-performance concrete (HPC) without and with 0.2% polypropylene fiber (PPHPC) was tested by mercury intrusion porosimetry, combining with fractal theory, the high temperature, PP fiber, pore parameters and fractal dimension was discussed. Results showed that porosity, the most probable pore size, the volume intermediate pore size and the threshold pore size all increase with the rising of temperature, the deterioration of the internal pore structure becomes serious. The pore growth rate of HPC is higher than PPHPC, and the porosity of HPC is about the same as PPHPC at 600°C. With temperature gradually increased, the fractal dimension of HPC increases first and then decreases, and the PPHPC shows a decreasing trend as a whole. The incorporation of PP fibers improves the internal connectivity of materials, reduces the deterioration of micro-structure after high temperature.