Full text
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| Author(s): |
Winnie Franco Santos
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: | 2016-04-04 |
| Examining board members: |
Sérgio Cirelli Angulo;
Eliane Betânia Carvalho Costa;
Rafael Giuliano Pileggi
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| Advisor: | Sérgio Cirelli Angulo |
| Abstract | |
The proposal aims to reduce the water absorption of the Construction and Demolition Waste (CDW) recycled aggregates through hydrophobic surface treatment, so that these do not increase the concretes water consumption (nor reduce de mechanical strength). The CDW recycled aggregates were characterized regarding granulometry, morphology, porosity, apparent contact angle, water absorption, image analysis and surface roughness. Then they had their surface treated with two types of water-repellent: silane solution and paraffin. All treatments have reduced water absorption of the CDW recycled aggregate. Immersion treatment was the one that allowed the best results and the lowest variability between techniques. The treatments repel water on surface, despite the paraffin presenting better wettability. Paraffin treatment showed, in terms of water absorption, lower and less variable results than silane did. Roughness parameters found that both materials lose their topographic profile when treating with paraffin. The different recycled aggregates with each repellent were applied in cementitious materials analyzed in fresh and hardened state. The treatments reduced absorption and mixing consumption of water in the mixing, but adversely affect mechanical properties due to the new interface created (paraffin wax in special) and the lack of wettability on surfaces. (AU) | |
| FAPESP's process: | 13/14307-0 - SUPERFICIAL TREATMENT OF RECYCLED CDW AGGREGATE WITH SILANE |
| Grantee: | Winnie Franco Santos |
| Support Opportunities: | Scholarships in Brazil - Master |