Passive control of bilinear hysteretic structures by tuned mass damper for narrow band seismic motions

• Inelastic structures are controlled by TMD under narrow band seismic motions.
• Minimax optimizations are on the nonlinear responses within the concerned frequency band.
• The stroke limits are considered on the proposed TMD design for practicality.
• Numerical verification includes nonlinear time history analyses under long distance earthquakes.
• More even damage reduction is achievable within the frequency band than conventional method.

Tuned mass damper (TMD) has been extensively used in vibration control of engineering structures. Numerous available results show that TMD can greatly reduce the response of elastic structures under wind, water waves, and earthquakes. The efficiency of TMDs, however, decreases when primary system experiences nonlinear behaviors. In order to make use of TMDs in such situations, this paper investigates the feasibility of adopting TMD in controlling of inelastic structures subjected to seismic motions. The focus is to explore the performance of TMD controlled buildings in areas subjected to long distance earthquakes, where structures usually have low nonlinearity. An optimization criterion is proposed to minimize the maximum nonlinear response within the concerned frequency band of excitations, instead of conventional approach whereby the linear response of the primary system is minimized. The limit on stroke is taken into consideration for practicality. Through numerical studies, it is shown that the primary structures achieve much better damage reduction by adopting the optimal TMD parameters based on the proposed criterion.