Helena Paiva

Dr. Helena Paiva


Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 May 2021 in Construction and Building Materials
Verified
Journal Article
Closed access
HMHamid Maljaee
Hamid Maljaee
RMRozita Madadi
Rozita Madadi
HPHelena Paiva
Helena Paiva
Luis TarelhoLuis Tarelho
Luis Tarelho
Victor FerreiraVictor Ferreira
Victor Ferreira

1 April 2012 in Cement and Concrete Research
Verified
Journal Article
Closed access
HPHelena Paiva
Helena Paiva
Ana Luísa VelosaAna Luísa Velosa
Ana Luísa Velosa
Paulo CachimPaulo Cachim
Paulo Cachim
Victor FerreiraVictor Ferreira
Victor Ferreira

1 February 2009 in Construction and Building Materials
Verified
Journal Article
Closed access
HPHelena Paiva
Helena Paiva
LEL.P. Esteves
L.P. Esteves
Paulo CachimPaulo Cachim
Paulo Cachim
Victor FerreiraVictor Ferreira
Victor Ferreira

1 February 2009 in Construction and Building Materials
Verified
Journal Article
Closed access
MSMaria Paula Seabra
Maria Paula Seabra
HPHelena Paiva
Helena Paiva
JLJoao A. Labrincha
Joao A. Labrincha
Victor FerreiraVictor Ferreira
Victor Ferreira

1 July 2006 in Cement and Concrete Research
Verified
Journal Article
Closed access
HPHelena Paiva
Helena Paiva
LSluis silva
luis silva
JLJoao A. Labrincha
Joao A. Labrincha
Victor FerreiraVictor Ferreira
Victor Ferreira

15 February 2019 in Sustainability
Verified
Journal Article
Open access
PDF file
HPHelena Paiva
Helena Paiva
Juho YliniemiJuho Yliniemi
Juho Yliniemi
MIMirja Illikainen
Mirja Illikainen
Fernando RochaFernando Rocha
Fernando Rocha
Victor FerreiraVictor Ferreira
Victor Ferreira
The demand for low environmental impact of materials in our habitat is one of the current societal challenges. Along with other solutions of waste valorisation, alkali activation as geopolymers can be one possible solution of waste valorisation because they may allow, for instance, an alternative solution for cement-based materials in some applications and it is one contribution for circular economy. This work has focused on the development and processing of geopolymers that incorporates as a fine aggregate a high-sulfidic mining waste (mine tailing), a difficult waste to process. Rheology analysis was applied as an important step to understand not only the geopolymers behaviour but also its transition from the fresh to the hardened state. The effect of precursor binder type (metakaolin or blast furnace slag), of mine tailing content and also the effect of temperature and curing conditions of different formulations were studied in this solution. It was possible to conclude that although this particular mine tailing is not a geopolymer binder precursor, it may be incorporated as an alternative fine aggregate in construction products. Furthermore, rheology could be used to follow up the geopolymer alkali-activation process and even to setup proper curing conditions and components contents in order to optimize the final mechanical strength of this material as a waste management solution. The final properties of these geopolymers compositions were adequate and after 28 days of curing, these geopolymers exhibit significant chemical resistance under severe test conditions.