In Situ Analysis of Moisture in Cement Based Materials

An approach for the evaluation of moisture transport in porous media is introduced and demonstrated through measurement of capillary absorption and evaporative drying in cement mortar. The sensing method is based on the application of Near-Infrared spectroscopy, where the internal environment of the cement mortar is monitored by measurement the absorption peaks of the water molecule using light traveling through an optical fiber. The fibers were altered by replacing a short length of the fiber cladding with a porous membrane, allowing the propagating light to interact with the water in the surrounding pore space, registering the respective moisture content.