Concrete Moisture Migration under High Temperatures: Grammar Analysis

Yes, the grammar of the sentences is correct.

Stelzner et al. (2019) investigated the behavior of moisture migration in concrete under high temperatures using CT scanning. Their findings revealed that moisture migration in concrete at 800 ℃ occurred at a very slow pace. Although the moisture content in the low-temperature region increased at high temperatures, the rate of increase was also slow. Li (2005) reported that the mobility of liquid water in concrete could be disregarded based on their experimental results. It was concluded that liquid water could not move in concrete within a short time frame, except during the occurrence of cracks. The presence of cracks in concrete allowed the rapid migration of liquid water through them. Therefore, the depth of cracks in concrete can be determined by observing water and vapor overflowing from cracks on the fire-unexposed surface of the concrete under fire.