{'fraction_non_alphanumeric': 0.01564537157757497, 'fraction_numerical': 0.009126466753585397, 'mean_word_length': 5.0, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Specialized optical fibre sensor array for structural damage detection

We describe a sensor system for damage detection in concrete structures after extreme events such as earthquakes. The system employs large array of optical fibres (up to 256 fibres) that are either embedded in, or bonded to the surface of the structural element or elements under test. A structural damage (cracks or complete failure) results in breaking of one or several optical fibres and sharp decrease in their optical transmission. The fibres are interrogated using a matrix-type optical fibre circuit with 16 optical transmitters and 16 optical receivers that operate in the TDM mode. This type of system can be used for monitoring of large arrays of other intensity-type optical sensors.