Temperature development in microwave cured repair materials

Abstract

This paper is part of the FP7 MCure project on the development and demonstration of an energy efficient system for accelerated curing during repair of concrete structures. It provides laboratory results on temperature development in microwave cured specimens of six commercial repair materials and a CEM II mortar. Specimens were cast in 100 mm polystyrene moulds and exposed to 60 Watts microwave power to reach approximately 40 °C recommended temperature for microwave curing. Temperature development of specimens was monitored for 24 hours after mixing. The results show that microwave curing triggers the peak heat of hydration and brings it forward for all repair materials. In addition, internal temperatures of specimens are higher than the top surface temperatures and the difference increases with increasing temperature. These laboratory based results are backed by the currently confidential data obtained from pre-industry prototype tests which are being used to upgrade the technology to industrial scale.