{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T04:10:44Z","timestamp":1767845444139,"version":"3.49.0"},"reference-count":28,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2010,11,10]],"date-time":"2010-11-10T00:00:00Z","timestamp":1289347200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents the feasibility of utilizing fiber Bragg grating (FBG) and long-period fiber grating (LPFG) sensors for nondestructive evaluation (NDE) of infrastructures using Portland cement concretes and asphalt mixtures for temperature, strain, and liquid-level monitoring. The use of hybrid FBG and LPFG sensors is aimed at utilizing the advantages of two kinds of fiber grating to implement NDE for monitoring strains or displacements, temperatures, and water-levels of infrastructures such as bridges, pavements, or reservoirs for under different environmental conditions. Temperature fluctuation and stability tests were examined using FBG and LPFG sensors bonded on the surface of asphalt and concrete specimens. Random walk coefficient (RWC) and bias stability (BS) were used for the first time to indicate the stability performance of fiber grating sensors. The random walk coefficients of temperature variations between FBG (or LPFG) sensor and a thermocouple were found in the range of \u22120.7499 \u00b0C\/ to \u22121.3548 \u00b0C\/. In addition, the bias stability for temperature variations, during the fluctuation and stability tests with FBG (or LPFG) sensors were within the range of 0.01 \u00b0C\/h with a 15\u201318 h time cluster to 0.09 \u00b0C\/h with a 3\u20134 h time cluster. This shows that the performance of FBG or LPFG sensors is comparable with that of conventional high-resolution thermocouple sensors under rugged conditions. The strain measurement for infrastructure materials was conducted using a packaged FBG sensor bonded on the surface of an asphalt specimen under indirect tensile loading conditions. A finite element modeling (FEM) was applied to compare experimental results of indirect tensile FBG strain measurements. For a comparative analysis between experiment and simulation, the FEM numerical results agreed with those from FBG strain measurements. The results of the liquid-level sensing tests show the LPFG-based sensor could discriminate five stationary liquid-levels and exhibits at least 1,050-mm liquid-level measurement capacity. Thus, the hybrid FBG and LPFG sensors reported here could benefit the NDE development and applications for infrastructure health monitoring such as strain, temperature and liquid-level measurements.<\/jats:p>","DOI":"10.3390\/s101110105","type":"journal-article","created":{"date-parts":[[2010,11,11]],"date-time":"2010-11-11T03:48:00Z","timestamp":1289447280000},"page":"10105-10127","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":47,"title":["Feasibility of Fiber Bragg Grating and Long-Period Fiber Grating Sensors under Different Environmental Conditions"],"prefix":"10.3390","volume":"10","author":[{"given":"Jian-Neng","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Construction Engineering, National Yunlin University of Science and Technology, Douliou 64002, Taiwan"}]},{"given":"Jaw-Luen","family":"Tang","sequence":"additional","affiliation":[{"name":"Department of Physics, National Chung Cheng University, Chia-Yi 62102, Taiwan"}]}],"member":"1968","published-online":{"date-parts":[[2010,11,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"330","DOI":"10.1016\/S0924-4247(02)00429-6","article-title":"Structural health monitoring of smart composite materials by using the EFPI and FBG sensors","volume":"103","author":"Leng","year":"2003","journal-title":"Sens. Actuat. A Phys"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1016\/S0963-8695(01)00060-3","article-title":"Non-destructive evaluation of smart materials by using extrinsic Fabry\u2014Perot interferometric and fiber Bragg grating sensors","volume":"35","author":"Leng","year":"2002","journal-title":"NDT E. Int"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"249","DOI":"10.1088\/0964-1726\/11\/2\/308","article-title":"Real-time cure monitoring of smart composite materials using extrinsic Fabry-Perot interferometer and fiber Bragg grating sensors","volume":"11","author":"Leng","year":"2002","journal-title":"Smart Mater. Struct"},{"key":"ref_4","unstructured":"Udd, E (1995). Fiber Optic Smart Structures, Wiley."},{"key":"ref_5","unstructured":"Culshaw, B, and Dakin, J (1997). Optical Fiber Sensors: Applications, Analysis, and Future, Artech House."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1828","DOI":"10.1016\/j.engstruct.2005.04.023","article-title":"Development of fiber Bragg grating sensors for monitoring civil infrastructure","volume":"27","author":"Moyoa","year":"2005","journal-title":"Eng. Struct"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Kersey, AD, Berkoff, TA, and Morey, WW (1992, January 12\u201314). Fiber-optic Bragg grating strain sensor with phase sensitive detection. Glasgow, UK.","DOI":"10.1117\/12.2298037"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1085","DOI":"10.1049\/el:19940746","article-title":"Discrimination between strain and temperature effects using dual-wavelength fiber grating sensors","volume":"30","author":"Xu","year":"1994","journal-title":"Electron. Lett"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1364\/OL.20.000333","article-title":"Simultaneous strain and temperature sensing with photogenerated in-fiber gratings","volume":"20","author":"Kanellopouslos","year":"1995","journal-title":"Opt. Lett"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1223","DOI":"10.1109\/68.531843","article-title":"Hybrid fiber Bragg grating\/long period fiber grating sensors for strain\/temperature discrimination","volume":"8","author":"Patrick","year":"1996","journal-title":"IEEE Photonic. Technol. Lett"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1133","DOI":"10.1049\/el:19960732","article-title":"Simultaneous independent temperature and strain measurement using in-fiber Bragg grating sensors","volume":"32","author":"James","year":"1996","journal-title":"Electron. Lett"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1118","DOI":"10.1364\/AO.39.001118","article-title":"Simultaneous measurement of strain and temperature using a single FBG grating with erbium-dopped fiber amplifier","volume":"39","author":"Jung","year":"2000","journal-title":"Appl. Opt"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1049\/ip-opt:19971271","article-title":"Simultaneous measurement of temperature and strain using fiber Bragg grating and Brillouin scattering","volume":"144","author":"Davis","year":"1997","journal-title":"IEE Proc. Optoelectron"},{"key":"ref_14","unstructured":"Othonos, A, and Kalli, K (1999). Fiber Bragg Grating: Fundamentals and Applications in Telecommunications and Sensing, Artech House Inc."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"6582","DOI":"10.3390\/s100706582","article-title":"Error analysis and measurement uncertainty for a fiber grating strain-temperature sensor","volume":"10","author":"Tang","year":"2010","journal-title":"Sensors"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1606","DOI":"10.1109\/50.712243","article-title":"Analysis of the response of long period fiber gratings to external index of refraction","volume":"16","author":"Patrick","year":"1998","journal-title":"J. Lightwave Technol"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"665","DOI":"10.1088\/0964-1726\/16\/3\/013","article-title":"Measurement of chloride ion concentration in concrete structures with long-period grating technology","volume":"16","author":"Tang","year":"2007","journal-title":"Smart Mater. Struct"},{"key":"ref_18","first-page":"100","article-title":"Chemical sensing sensitivity of long-period grating sensor enhanced by colloidal gold nanoparticles","volume":"7","author":"Tang","year":"2008","journal-title":"Sensors"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1574","DOI":"10.1109\/50.956145","article-title":"High temperature stability of long-period fiber gratings produced using an electric arc","volume":"19","author":"Rego","year":"2001","journal-title":"J. Lightwave Technol"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"R49","DOI":"10.1088\/0957-0233\/14\/5\/201","article-title":"Optical fibre long-period grating sensors: Characteristics and application","volume":"14","author":"James","year":"2003","journal-title":"Meas. Sci. Technol"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1872","DOI":"10.1117\/1.601379","article-title":"Temperature-insensitive and strain-insensitive long-period gratings sensor for smart structures","volume":"36","author":"Bhatia","year":"1997","journal-title":"Opt. Eng"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1117\/12.275736","article-title":"Temperature-insensitive long-period grating for strain and refractive index sensing","volume":"3042","author":"Bhatia","year":"1997","journal-title":"Proc. SPIE"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1224","DOI":"10.1364\/OL.26.001224","article-title":"Fiber-optic liquid-level sensor using a long-period grating","volume":"26","author":"Khaliq","year":"2001","journal-title":"Opt. Lett"},{"key":"ref_24","unstructured":"McGennis, RB, Anderson, RM, Kennedy, TW, and Solaimanian, M (1995). Background of Superpave Asphalt Mixture Design and Analysis, US Department of. Transportation, Federal Highway Administration. Publication No. FHWA-SA-95-003."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"238","DOI":"10.1061\/(ASCE)0899-1561(2000)12:3(238)","article-title":"Volumetric and mechanical performance properties of the Superpave mixtures","volume":"12","author":"Wang","year":"2000","journal-title":"J. Mater. Civil Eng. ASCE"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2980","DOI":"10.1088\/0957-0233\/17\/11\/018","article-title":"A wavelet-based bootstrap method applied to inertial sensor stochastic error modelling using the Allan variance","volume":"17","author":"Sabatini","year":"2006","journal-title":"Meas. Sci. Technol"},{"key":"ref_27","unstructured":"IEEE, Standard 952-1997 (1997)."},{"key":"ref_28","unstructured":"Stockwell, W Available online: http:\/\/www.xbow.com\/Support\/Supportpdffiles\/BiasStabilityMeasurement.pdf (accessed on 28 September 2010)."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/11\/10105\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:03:49Z","timestamp":1760220229000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/11\/10105"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,11,10]]},"references-count":28,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2010,11]]}},"alternative-id":["s101110105"],"URL":"https:\/\/doi.org\/10.3390\/s101110105","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2010,11,10]]}}}