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| Author(s): |
João Adriano Rossignolo
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Física de São Carlos (IFSC/BT) |
| Defense date: | 2003-01-08 |
| Examining board members: |
Marcos Vinicio Costa Agnesini;
Osny Pellegrino Ferreira;
Jasson Rodrigues de Figueiredo Filho;
Vladimir Antonio Paulon;
Milton Ferreira de Souza
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| Advisor: | Marcos Vinicio Costa Agnesini |
| Abstract | |
This dissertation deals with the application of the high performance lightweight aggregate concrete (HPLWAC) for the production of thin precast components, such as structural and insulation panels and elements for covering. A concrete with special properties was presented, once the use of styrene-butadiene latex (SBR), silica fume, accelerating superplastificizer and Brazilian lightweight aggregates, named SBR-modified high performance lightweight aggregate concrete. Our main goals in the experimental program were the study of concrete dosage and production, the characterization of concretes properties, the thin precast components analysis, as well as the microstructural study about both cement paste and the interfacial transition zone (ITZ) between aggregate and cement paste. The main results show that the SBR-modified HPLWAC are extremely appropriate to the production of thin precast components, due essentially to the density reduction and to the high performance of mechanical and durability properties. Besides this, it was viewed that the silica fume and SBR use promote the decrease of the amount and diameter of the capillary pores, as well as the amount of calcium hydroxide (CH) in the cement paste. Additionally, they reduce the thickness of the interfacial transition zone between aggregate and cement paste. It was also observed that the concretes with Brazilian lightweight aggregate presented lower values of the interfacial transition zone thickness than the ones observed for the concretes with traditional aggregates (basalt). (AU) | |