Niederleithinger Ernst, Wolf Julia, Mielentz Frank, Wiggenhauser Herbert, Pirskawetz Stephan
BAM Federal Institute for Materials Research and Testing, Berlin 12200, Germany.
Sensors (Basel). 2015 Apr 27;15(5):9756-72. doi: 10.3390/s150509756.
Recently developed new transducers for ultrasonic transmission, which can be embedded right into concrete, are now used for non-destructive permanent monitoring of concrete. They can be installed during construction or thereafter. Large volumes of concrete can be monitored for changes of material properties by a limited number of transducers. The transducer design, the main properties as well as installation procedures are presented. It is shown that compressional waves with a central frequency of 62 kHz are mainly generated around the transducer's axis. The transducer can be used as a transmitter or receiver. Application examples demonstrate that the transducers can be used to monitor concrete conditions parameters (stress, temperature, …) as well as damages in an early state or the detection of acoustic events (e.g., crack opening). Besides application in civil engineering our setups can also be used for model studies in geosciences.
最近开发的用于超声波传输的新型换能器，可直接嵌入混凝土中，现用于混凝土的无损永久监测。它们可以在施工期间或之后安装。通过有限数量的换能器，可以监测大量混凝土的材料特性变化。介绍了换能器的设计、主要特性以及安装程序。结果表明，中心频率为62kHz的压缩波主要在换能器轴周围产生。该换能器可用作发射器或接收器。应用实例表明，这些换能器可用于监测混凝土状况参数（应力、温度等）以及早期损伤或声学事件（如裂缝张开）的检测。除了在土木工程中的应用，我们的装置还可用于地球科学的模型研究。
