Visualizing mechanical strain/stress changes is an emerging area in structural health monitoring. Several ways are
available for strain change visualization through the color/brightness change of the materials subjected to the mechanical
stresses, for example, using mechanoluminescence (ML) materials and mechanoresponsive polymers (MRP). However,
these approaches were not effectively applicable for civil engineering system yet, due to insufficient sensitivity to low-level
strain of typical civil structures and limitation in measuring both static and dynamic strain. In this study, design and
validation for high-sensitivity strain visualization using electroluminescence technologies are presented. A high-sensitivity
Wheatstone bridge, of which bridge balance is precisely controllable circuits, is used with a gain-adjustable
amplifier. The monochrome electroluminescence (EL) technology is employed to convert both static and dynamic strain
change into brightness/color change of the EL materials, through either brightness change mode (BCM) or color
alternation mode (CAM). A prototype has been made and calibrated in lab, the linearity between strain and brightness
change has been investigated.
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