| The development of accelerated test method for
Internal Sulfate Attack by delayed ettringite formation |
| Tác giả hoặc Nhóm tác giả: Van-Huong Nguyen, Nordine Leklou, Pierre Mounanga |
| Nơi đăng: Materials Science Forum; Số: 987;Từ->đến trang: 27-32;Năm: 2020 |
| Lĩnh vực: Khoa học công nghệ; Loại: Bài báo khoa học; Thể loại: Quốc tế |
| TÓM TẮT |
| Delayed Ettringite Formation (DEF) is an internal sulfate attack caused
by heat-induced decomposition and/or prevention of normal ettringite
formed during the initial hydration of cement at elevated temperature
(above about 70°C) and its re-crystallization in the hardened matrix.
This reaction is a physico-chemical phenomenon inducing an expansion of
the cement paste that could lead to cracking of cementitious matrix.
These cracks result in a decrease in the mechanical performances and
durability parameters of the material. However, the internal sulfate
attack is characterized by a very slow reaction kinetics and therefore
it is difficult to study it in laboratories. This research developed an
accelerated method focused on mortar specimens; it is based on
electrochemical techniques in order to speed the leaching of alkalis
that could be accelerated the DEF.
|
| ABSTRACT |
| Delayed Ettringite Formation (DEF) is an internal sulfate attack caused by heat-induced decomposition and/or prevention of normal ettringite formed during the initial hydration of cement at elevated temperature (above about 70oC) and its re-crystallization in the hardened matrix. This reaction is a physico-chemical phenomenon inducing an expansion of the cement paste that could lead to cracking of cementitious matrix. These cracks result in a decrease in the mechanical performances and durability parameters of the material. However, the internal sulfate attack is characterized by a very slow reaction kinetics and therefore it is difficult to study it in laboratories. This research developed an accelerated method focused on mortar specimens; it is based on electrochemical techniques in order to speed the leaching of alkalis that could be accelerated the DEF. |
| [ 2020\2020m05d020_11_6_56MSF.987.27.pdf ] |
