Bao Yi, Hoehler Matthew S, Smith Christopher M, Bundy Matthew, Chen Genda
Department of Civil, Architectural, and Environmental Engineering, Missouri University of Science and Technology, 1401 N. Pine Street, Rolla, MO 65409.
National Fire Research Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899.
Smart Mater Struct. 2017 Oct;26(10). doi: 10.1088/1361-665X/aa89a9. Epub 2017 Sep 18.
In this study, distributed fiber optic sensors based on pulse pre-pump Brillouin optical time domain analysis (PPP-BODTA) are characterized and deployed to measure spatially-distributed temperatures in reinforced concrete specimens exposed to fire. Four beams were tested to failure in a natural gas fueled compartment fire, each instrumented with one fused silica, single-mode optical fiber as a distributed sensor and four thermocouples. Prior to concrete cracking, the distributed temperature was validated at locations of the thermocouples by a relative difference of less than 9 %. The cracks in concrete can be identified as sharp peaks in the temperature distribution since the cracks are locally filled with hot air. Concrete cracking did not affect the sensitivity of the distributed sensor but concrete spalling broke the optical fiber loop required for PPP-BOTDA measurements.
在本研究中，对基于脉冲预泵浦布里渊光时域分析（PPP-BODTA）的分布式光纤传感器进行了特性表征，并将其用于测量遭受火灾的钢筋混凝土试件中的空间分布温度。在以天然气为燃料的室内火灾中对四根梁进行了破坏试验，每根梁都安装了一根熔融石英单模光纤作为分布式传感器以及四个热电偶。在混凝土开裂之前，通过小于9%的相对差值在热电偶位置对分布式温度进行了验证。由于裂缝中局部充满热空气，混凝土中的裂缝可被识别为温度分布中的尖峰。混凝土开裂并未影响分布式传感器的灵敏度，但混凝土剥落破坏了PPP-BOTDA测量所需的光纤回路。
