Influence of acid treatment and carbonation on the properties of recycled concrete aggregate
Само за регистроване кориснике
2017
Чланак у часопису (Објављена верзија)
Метаподаци
Приказ свих података о документуАпстракт
Recycled concrete aggregate (RCA), obtained by crushing of original (old)
concrete, consists of natural aggregate grains and a cement mortar matrix. The
presence of old adhered cement mortar, which has higher porosity than natural
aggregate, causes unfavourable properties of RCA. The research conducted in
order to improve the quality of RCA and to enable its greater application in the
construction industry is presented in this paper. Therefore, RCA was subjected
to quality improvement treatments with hydrochloric acid and carbon dioxide
(accelerated carbonation). The first procedure was aimed at partially removing
the adhered cement mortar and the second at reinforcing the cement matrix. The
physical, mechanical and chemical properties of all three types of RCA were
tested. After the pre-soaking acid treatment (0.1 mol/dm3 HCl), RCA showed
reduced water absorption (up to 3%); the process of accelerated carbonation
also led to reduced water absorption (13–20%) as well as to ...improved mechanical
properties (∼10%). A scanning electron microscopy investigation revealed
that the carbonation process, as expected, significantly reduces porosity of RCA.
The overall results show that if RCA is obtained by crushing of compact, high-
-quality concrete, the procedures of aggregate quality improvement are not necessary
Кључне речи:
accelerated carbonation / pre-soaking in acid / recycled concrete aggregateИзвор:
Chemical Industry & Chemical Engineering Quarterly, 2017, 24(1)Финансирање / пројекти:
- TR 36048
- TR 36017
DOI: 10.2298/CICEQ161202014R
ISSN: 1451-9372