The Feasibility of Using Electromagnetic Waves in Determining Membrane Failure Through Concrete
Concrete flat roof defects, such as water leakage, present a significant and common problem in large buildings, particularly in tropical countries, where rainfall is high. To monitor this condition, effective non-destructive test methods are required to detect problems at an early stage, especially hidden defects within the concrete roof, which are critical. This paper presents the potential use of electromagnetic (EM) waves for determining possible leakage of the concrete flat roof as a result of failure of the waterproof membrane layer. This study was assessed, experimentally by the investigation of the propagation of EM waves through the roof and their interaction with water. Novel Microwave sensors described in the paper operate in the 6–12 GHz frequency range using a Marconi 6200A microwave test set. A range of existing methods were reviewed and analysed. Results of experimental tests confirmed that microwaves could be used as an alternative non-destructive method for identifying water ingress caused by membrane failure into the concrete roof surface.
KeywordsHorn antenna Electromagnetic waves Microwaves Sensor Concrete flat roof Membrane
The authors gratefully acknowledge the financial support of the University of Malaya Research Grant (UMRG), Grant No. RP007A/13SUS established at the University of Malaya, Sustainability Science Research Cluster.
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