Liquid nitrogen effect on the fresh concrete properties in hot weathering concrete

• Published in: Innovative infrastructure solutions : the official journal of the Soil-Structure Interaction Group in Egypt (SSIGE) 2022-02, Vol.7 (1), Article 127
• Main Authors: Harith, Iman Kattoof, Hassan, Maan S., Hasan, Shatha S.
• Format: Article
• Language: English
• Subjects: Earth and Environmental Science; Earth Sciences; Environmental Science and Engineering; Foundations; Geoengineering; Geotechnical Engineering & Applied Earth Sciences; Hydraulics; Technical Paper
• ISSN: 2364-4176; 2364-4184
• DOI: 10.1007/s41062-021-00731-6

The placement of concrete in hot weather regions is a major challenge due to thermal cracking and durability problems. Hence, the construction season is shortened by at least two months (July and August). This paper examines the cooling effects of liquid nitrogen (LN) at various levels on fresh concrete properties, including slump, setting time and temperature rise vs. time behaviour. Multiple mixtures of binary and ternary binders were produced, and the design of experiments (DoE) approach was followed to evaluate the efficiency of LN in improving the properties of fresh concrete against other alternatives. Considered independent variables were fly ash (up to 25%), nanosilica (up to 4%) and LN (up to 276 L/m 3 ). The experimental results showed that LN-cooled concrete has a promising potential in extending the construction season during summer periods in hot regions. Statistical models formulated based on the LN, fly ash, and nanosilica parameters revealed that LN was the most expedient means affecting the setting time, slump, and temperature rise vs. time measurements. Casting concrete in hot weather conditions required the use of up to 276 L/m 3 of LN to maintain concrete in workable conditions for extended periods (200% more).