A uniplanar capacitive sensor, with 5-electrode on one plane substrate and a large reflector electrode, is designed to get the corresponding capacitance information for weathering damage detection of nonmetallic materials exposed to a service environment. A 2-D finite-element method is employed to simulate the electric potential distribution and capacitance measurements for the sensor. 2 marble slabs, one is healthy and the other is notched, are used as a sample for the experiment of detecting the weathering damages. Both the simulation and the preliminary experimental results show that the measured capacitances decrease after weathering damage occurs in nonmetallic material, and that the proposed approach can effectively detect the weathering damage of nonmetallic material and can be practically used for in-situ weathering damage detection. The reflector can enlarge the sensitive depth. The weathering assessment of nonmetallic materials can also be done according to the obtained capacitance information.
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