Sensitivity Enhancement of Strain Sensor Based on Polymer Optical Fiber for Concrete Testing

Abstract

Research has been carried out about sensitivity enhancement of strain sensor based on polymer optical fiber used for concrete testing. Strain sensor testing was done by applying of pressure to the concrete using the Ultimate Testing Machine (UTM). Strain sensor was made from polymer optical fiber without coat with straight, U and rectangular configurations. At both ends of the sensor connected with Light Emitting Diode (LED), phototransistor and amplifier circuit that produces output value in the form of analog voltage that is converted by the Arduino Uno microcontroller into the digital voltage value displayed on the computer. The results showed that the greater the load given on the concrete, the greater the strain on the sensor, so that the output voltage read on the computer gets smaller. The best sensitivity value obtained at rectangular configuration with 3 cm amplitude is 0.117 V/cm with 0.008 cm resolution. Strain sensor in the concrete structures testing based on polymer optical fiber has advantages including low cost, simple measurement system, easy fabrication with high sensitivity.?