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| Author(s): |
Paulo Henrique Ferreira Loz
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2020-12-16 |
| Examining board members: |
Sérgio Cirelli Angulo;
Markus Samuel Rebmann;
Sandro Marden Torres
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| Advisor: | Sérgio Cirelli Angulo |
| Abstract | |
The roughness of aggregates influences the performance of the concrete in the fresh and hardened state. Aggregates with high roughness improve the properties at the pasteaggregate interface but increase the viscosity of the concrete due to the increased friction between the particles. Despite the importance of roughness there are no studies that perform a multiscale analysis (macro and micro), preventing a better understanding of its effects on concrete. Therefore, this work proposes a multiscale study of the roughness of different aggregates. For this purpose, the roughness of the aggregates was measured through optical interferometry, which provides quantitative data in 3D. Six types of aggregates were analyzed and presented different roughness in both scales (macro and micro). Petrographic analyses showed that the roughness may be related to the size and quantity of the grains in the microstructure of the rock. The 3D scanning was used to characterize the particle shape and complement the roughness data with the volume, allowing the determination of the volumetric surface area (VSA) of the aggregates at the microscale of observation. The physical measurement of the specific surface area (SSA) obtained by the methylene blue adsorption technique obtained evidence of good correlation with the interferometer SSA. (AU) | |
| FAPESP's process: | 17/25826-0 - Evaluation of natural coarse aggregates roughness and its influence on formation of macrodefects in the paste-aggregate interface |
| Grantee: | Paulo Henrique Ferreira Loz |
| Support Opportunities: | Scholarships in Brazil - Master |