Thermography as a technique for monitoring early age temperatures of hardening concrete

• Type: Article in International Scientific Journal
• Date: 2011

Authors

Miguel Azenha (Author) Other; Rui Faria (Author) FEUP; Helena Figueiras (Author) Other

Journal

Title: Construction and Building Materials

Vol. 25

Pages: 4232-4240

ISSN: 0950-0618

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 16 Citations

ISI Web of Science

Scopus - 22 Citations

Scientific classification

FOS: Engineering and technology > Civil engineering

Other information

Authenticus ID: P-002-KD4

DOI: 10.1016/j.conbuildmat.2011.04.065

Abstract (EN): The exothermal character of cement hydration reactions causes concrete to endure temperature changes during the first days after casting, with associated volumetric deformations that may induce undesired cracking. The capability to predict temperature evolution in concrete since casting is thus important to back decisions that avoid detrimental thermal cracking in concrete structures. Even though several approaches exist to model the early age behavior of concrete, the laboratory or in situ verification of numerical predictions is scarce, and mostly done with embedded temperature sensors, with limited sampling points. The present research intends to evaluate the performance of the thermography technique in the continuous monitoring of surface temperatures of a hydrating 0.40 x 0.40 x 0.40 m(3) concrete cube, in which embedded thermal sensors are also used. By using thermography, simultaneous monitoring of the visible surfaces of the specimen is possible, thus providing comprehensive information regarding the evolution of surface temperatures. The temperatures monitored with the thermography, as well as with the embedded temperature sensors, are finally used as a benchmark example for validation of a 3D finite element numerical code for thermal analysis developed by the authors. The use of thermography images for validation of finite element results is rather more advantageous than the use of standard single point temperature measurements, in view of the large facility and wide range of comparison provided by the simultaneous visualization of temperature surface color maps (measured and simulated).

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9