{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T12:27:39Z","timestamp":1777638459919,"version":"3.51.4"},"reference-count":29,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,4,17]],"date-time":"2018-04-17T00:00:00Z","timestamp":1523923200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper proposes the monitoring of old timber beams with natural defects (knots, grain deviations, fissures and wanes), reinforced using carbon composite materials (CFRP). Reinforcement consisted of the combination of a CFRP laminate strip and a carbon fabric discontinuously wrapping the timber element. Monitoring considered the use and comparison of two types of sensors: strain gauges and multi-resonant acoustic emission (AE) sensors. Results demonstrate that: (1) the mechanical behavior of the beams can be considerably improved by means of the use of CFRP (160% in bending load capacity and 90% in stiffness); (2) Acoustic emission sensors provide comparable information to strain gauges. This fact points to the great potential of AE techniques for in-service damage assessment in real wood structures.<\/jats:p>","DOI":"10.3390\/s18041224","type":"journal-article","created":{"date-parts":[[2018,4,18]],"date-time":"2018-04-18T03:51:13Z","timestamp":1524023473000},"page":"1224","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Monitoring of Carbon Fiber-Reinforced Old Timber Beams via Strain and Multiresonant Acoustic Emission Sensors"],"prefix":"10.3390","volume":"18","author":[{"given":"Francisco J.","family":"Rescalvo","sequence":"first","affiliation":[{"name":"Department of Applied Physics, University of Granada, Campus Fuentenueva s\/n, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ignacio","family":"Valverde-Palacios","sequence":"additional","affiliation":[{"name":"Department of Building Constructions, University of Granada, Campus Fuentenueva s\/n, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1725-7219","authenticated-orcid":false,"given":"Elisabet","family":"Suarez","sequence":"additional","affiliation":[{"name":"Department of Applied Physics, University of Granada, Campus Fuentenueva s\/n, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6807-7053","authenticated-orcid":false,"given":"Andr\u00e9s","family":"Rold\u00e1n","sequence":"additional","affiliation":[{"name":"Department of Electronics and Computer Technology, University of Granada, Campus Fuentenueva s\/n, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antolino","family":"Gallego","sequence":"additional","affiliation":[{"name":"Department of Applied Physics, University of Granada, Campus Fuentenueva s\/n, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,17]]},"reference":[{"key":"ref_1","first-page":"2010","article-title":"Directive 2010\/31\/EU of the European parliament and of the council of 19 May 2010 on the energy performance of buildings","volume":"18","author":"Commission","year":"2010","journal-title":"Off. 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