Assessment of compositional changes of carbonated cement pastes subjected to high temperatures using in-situ Raman mapping and XPS
Artikel i vetenskaplig tidskrift, 2022

This paper presents a new method for assessing the compositional changes of carbonated cement pastes subjected to high temperatures. In this new method, in-situ Raman mapping combined with X-ray photoelectron spectroscopy (XPS) was used to monitor the phase transformation in carbonated cement pastes subjected to various high temperatures from 30 to 950 degrees C. Two kinds of carbonated areas, i.e., vaterite dominated and calcite dominated, were found in the in-situ Raman measurements. With the elevation in temperature, most of the vaterite was converted to calcite at 500 degrees C and completely decomposed at 600 degrees C, while the decomposition of calcite started at 600 degrees C and finished at 720 degrees C. Meanwhile, the depolymerization of the calcium modified silica gel to the silicate phases with a lower degree of polymerization was initiated at 500 degrees C, which led to the crystallization of beta-C2S at 600 degrees C. The generation of beta-C2S was found to increase with the elevation in temperature and became the dominant phase at 950 degrees C. In conclusion, the high temperature could affect the stability of carbonated cement pastes at 500 degrees C and above. The in-situ Raman mapping measurement has provided an extraordinary view of the spatial distribution of interesting phases subjected to high temperatures in a nondestructive way, which should be more consistent with the true condition in the material.

High temperature

Carbonation

In-situ Raman mapping

Cement pastes

XPS

Författare

Yongqiang Li

China Earthquake Administration

Chalmers, Arkitektur och samhällsbyggnadsteknik, Byggnadsteknologi

Shenzhen University

Tangwei Mi

Shenzhen University

Xiaobo Ding

Shenzhen University

Wei Liu

Shenzhen University

Biqin Dong

Shenzhen University

Zhijun Dong

ShenZhen Institute of Information Technology

Luping Tang

Chalmers, Arkitektur och samhällsbyggnadsteknik, Byggnadsteknologi

Feng Xing

Shenzhen University

China Earthquake Administration

Journal of Building Engineering

2352-7102 (eISSN)

Vol. 45 103454

Ämneskategorier

Oorganisk kemi

Keramteknik

Materialkemi

DOI

10.1016/j.jobe.2021.103454

Mer information

Senast uppdaterat

2021-11-16