Development of In Situ Water Absorption Method: Laboratory Study and Field Validation

Concrete porosity and its interconnection are crucial aspects that influence durability. Taking into account that moisture is required for many concrete deterioration processes, water absorption is a measure that can essentially evaluate concrete quality and its resistance. Standardized laboratory methods exist to measure water absorption. It is also potentially possible to perform simple and rapid nondestructive water absorption tests on placed concrete; however, it is impossible to provide standard conditions for in situ measurements. Because water absorption is strongly affected by temperature as well as relative humidity (RH), on-site water absorption measurements require cautious interpretation. This study addresses the issue by investigating water absorption in different thermal and moisture conditions. Concrete water absorption tests were performed using a commercial test device over a range of RH and temperature levels. It was observed that water absorption increases significantly with decreasing moisture content and increasing environmental temperature. Surface RH was found as an accurate and practical indicator of concrete moisture content. Most notably, outdoor exposure measurements confirmed that using a temperature correction, field results correlated very well to laboratory predictions making the test reliable for quality control purposes. (C) 2017 American Society of Civil Engineers.