Equivalent Linearization Method for Nonlinear Structure System Added with Oil Damper(PDF)
《建筑科学与工程学报》[ISSN:1673-2049/CN:61-1442/TU]
- Issue:
- 2018年03期
- Page:
- 44-53
- Research Field:
- Publishing date:
Info
- Title:
- Equivalent Linearization Method for Nonlinear Structure System Added with Oil Damper
- Author(s):
- PU Wu-chuan; LI Qi
- School of Civil Engineering and Architecture, Wuhan University of Technology
- Keywords:
- seismic control; oil damper; equivalent linearization; nonlinear structure; earthquake response
- PACS:
- -
- DOI:
- -
- Abstract:
- Taking the single degree of freedom nonlinear structure system added with oil damper as study object, an equivalent linearization method of the nonlinear structure system under earthquake was proposed. The structure system behaved bilinearly character, the relationship between damping force and velocity of oil damper was bilinear, and the main structure behaved bilinearly hysteretic characteristics. The main structure was equated to a linear Kelvin model, and the added system was equated in a twostep way: bilinearly viscous element was equated to a linearly viscous element, then the added system with linear viscous element was connected to the Kelvin model of main structure in parallel, namely model A; based on model A, the equivalent damping ratio and equivalent period were derived, and the system was equated simply to a Kelvin model, namely model B. The accuracies of the two models were investigated by comparing the resonance curves, respectively. Considering the randomness of earthquake excitation, the equivalent damping ratio computed from model B was further revised based on nonlinear time history analysis. The equivalent linearization method was expanded to performance curves, and the drawing method for damping performance curves of nonlinear structure system was established. The damping effect of oil damper on nonlinear structure was analyzed combined performance curves. The results show that the resonance curves of model A and model B both coincide the original structure respectively, which proves bilinearly viscous element equivalent to a linearly viscous element in nonlinear structure is feasible. The revised equivalent damping ratio can effectively predict the peak displacement of nonlinear structural systems under earthquake.
Last Update: 2018-05-31