{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T18:42:14Z","timestamp":1785436934176,"version":"3.56.0"},"reference-count":44,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T00:00:00Z","timestamp":1776211200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Basic Research Program of Jiangsu","award":["BK20241519, BK20250286"],"award-info":[{"award-number":["BK20241519, BK20250286"]}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["2023M740982"],"award-info":[{"award-number":["2023M740982"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2023M740982"],"award-info":[{"award-number":["2023M740982"]}],"id":[{"id":"https:\/\/ror.org\/0426zh255","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012226","name":"Fundamental Research Funds for the Central Universities","doi-asserted-by":"publisher","award":["B240201047"],"award-info":[{"award-number":["B240201047"]}],"id":[{"id":"10.13039\/501100012226","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52579119"],"award-info":[{"award-number":["52579119"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["52579119"],"award-info":[{"award-number":["52579119"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Nanjing Funding Scheme for Scientific and Technological Innovation Projects by Selected Re-turned Overseas Chinese Scholars","award":["Rc124006"],"award-info":[{"award-number":["Rc124006"]}]},{"name":"Open Research Fund of Jiangxi Academic of Water Science and Engineering","award":["2023SKSG06"],"award-info":[{"award-number":["2023SKSG06"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper proposes a novel parametric output-only modal identification method, termed parametric complexity pursuit (PCP), for accurate identification of modal parameters in civil engineering structures. The proposed method extends the complexity pursuit (CP) algorithm through a system representation. Unlike the standard CP approach, which extracts modes individually, the PCP algorithm transforms CP into a parametric formulation that enables global identification of all modal parameters of interest. This parametric framework provides a rigorous theoretical foundation aligned with structural dynamics and explicitly accounts for mutual influences among different modes, thereby enhancing both accuracy and robustness. Numerical experiments on a simulated 3-DOF system under various damping conditions and closely spaced modes demonstrate that PCP maintains consistent identification accuracy across all damping levels, exhibiting true damping-independent performance. In contrast, conventional CP suffers from marked accuracy degradation as damping increases and fails to properly identify the closely spaced modes. Application to the HCT building further confirms the practical effectiveness of PCP, with comparative analysis demonstrating its superiority over existing output-only techniques in modal separation capability and identification accuracy. The proposed PCP method offers a robust and theoretically grounded framework for output-only modal identification, particularly advantageous in challenging scenarios involving high damping and closely spaced modes.<\/jats:p>","DOI":"10.3390\/s26082417","type":"journal-article","created":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T12:25:30Z","timestamp":1776255930000},"page":"2417","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Output-Only Modal Identification of Civil Engineering Structures Based on Parametric Complexity Pursuit"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3080-3854","authenticated-orcid":false,"given":"Jianming","family":"Li","sequence":"first","affiliation":[{"name":"College of Mechanics and Engineering Science, Hohai University, 8 Fochengxi Road, Nanjing 211100, China"},{"name":"Jiangsu Huatong Engineering Technology Co., Ltd., Nanjing 210017, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6257-1616","authenticated-orcid":false,"given":"Jinjin","family":"Gao","sequence":"additional","affiliation":[{"name":"Nanjing Hydraulic Research Institute, 225 Guangzhou Road, Nanjing 210029, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shixiang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Jiangsu Huatong Engineering Technology Co., Ltd., Nanjing 210017, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Violeta","family":"Mircevska","sequence":"additional","affiliation":[{"name":"Institute of Earthquake Engineering and Engineering Seismology, Ss. Cyril and Methodius University in Skopje, Todor Aleksandrov Street, 1000 Skopje, North Macedonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maosen","family":"Cao","sequence":"additional","affiliation":[{"name":"College of Mechanics and Engineering Science, Hohai University, 8 Fochengxi Road, Nanjing 211100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"109175","DOI":"10.1016\/j.ymssp.2022.109175","article-title":"Vibration feature extraction using signal processing techniques for structural health monitoring: A review","volume":"177","author":"Zhang","year":"2022","journal-title":"Mech. Syst. 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