Experimental research on the time-varying law of performance for natural rubber laminated bearings subjected to seawater dry-wet cycles. (15th September 2019)

• Record Type: Journal Article
• Authors: Ma, Yuhong; Li, Yanmin; Zhao, Guifeng; Zhou, Fulin
• Is Part Of: Engineering structures. Volume 195(2019)
• Page Start: 159
• Page End: 171
• Publication Date: 2019-09-15
• Subjects: Seawater dry-wet cycles -- Natural rubber bearing -- Basic performance -- Time-varying law; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2019.05.101
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Seawater dry-wet cycles test is carried out to investigate its effect on the properties of LNR. Change laws of both the material parameters of LNR's constitutive model Mooney-Rivlin and the horizontal and vertical stiffness of LNR with time, are obtained. Accuracy of the material parameters of LNR's constitutive model Mooney-Rivlin is verified by comparing test results with simulation results of the properties of LNR before and after test. Performance deterioration law of the LNRs was predicted over a 120-year lifespan based on the test results. Abstract: Natural rubber laminated bearings (NRBs) in sea-crossing or offshore bridges are extremely vulnerable to seawater dry-wet cycles due to weather conditions, wind, waves, and other factors in coastal areas. Seawater dry-wet cycles test was conducted on 20 NRBs and 63 rubber sheets for 60 days to investigate the influence of seawater dry-wet cycles on basic NRB performance. The change laws that govern the NRBs' horizontal and vertical stiffness were obtained via seawater dry-wet cycles test. In addition, the proposed constitutive parameters of the rubber material were used to establish a finite-element model of the NRBs to simulate and analyze the bearings' performance and time-varying law. The test results were then compared with the fitted and simulated results. Finally, the performance deterioration law of the NRBs was predicted over a 120-year lifespan based on the extrapolation of the 60-day test results, and the finite element analysis of the performance for NRB within 120-year service life was done to verify the reliable of the prediction result. The 60 days test results show that the NRBs' horizontal and vertical stiffness increased by 23% and 7%, respectively, after test for 60 days, and horizontal and vertical stiffness increased linearly as the seawater dry-wet cycles test time increased. The findings presented in this paper lay a foundation for further research on the performance of NRBs and will play an important role in the study of the seismic resistance and life-cycle performance of sea-crossing bridges and other structures subjected to seawater dry-wet cycles.