This paper presents a clipped-optimal control strategy for magnetorheological (MR) dampers to reduce structural responses due to seismic loads. The study focuses on the modeling and control of MR dampers for seismic response reduction. MR dampers are a new class of semi-active control devices that use MR fluids to provide controllable dampers with low power requirements, making them suitable for seismic applications. The paper proposes a clipped-optimal acceleration feedback control strategy for MR dampers, which is based on a recently developed model of an MR damper. The model accurately reproduces the behavior of the MR damper and is used to demonstrate the effectiveness of the control strategy through a numerical example. The control strategy is designed to adjust the command voltage of the MR damper to approximate the optimal force level. The effectiveness of the MR damper using the proposed clipped-optimal control law is demonstrated through a numerical example. The results show that the clipped-optimal controller performs better than both passive-off and passive-on control systems. The study also compares the performance of the semi-active control system with that of a fully active control system. The results indicate that the semi-active control system is capable of not only approaching but surpassing the performance of the fully active control system while requiring only a small fraction of the power. The study concludes that the semi-active control system based on MR dampers is a promising approach for seismic response reduction.This paper presents a clipped-optimal control strategy for magnetorheological (MR) dampers to reduce structural responses due to seismic loads. The study focuses on the modeling and control of MR dampers for seismic response reduction. MR dampers are a new class of semi-active control devices that use MR fluids to provide controllable dampers with low power requirements, making them suitable for seismic applications. The paper proposes a clipped-optimal acceleration feedback control strategy for MR dampers, which is based on a recently developed model of an MR damper. The model accurately reproduces the behavior of the MR damper and is used to demonstrate the effectiveness of the control strategy through a numerical example. The control strategy is designed to adjust the command voltage of the MR damper to approximate the optimal force level. The effectiveness of the MR damper using the proposed clipped-optimal control law is demonstrated through a numerical example. The results show that the clipped-optimal controller performs better than both passive-off and passive-on control systems. The study also compares the performance of the semi-active control system with that of a fully active control system. The results indicate that the semi-active control system is capable of not only approaching but surpassing the performance of the fully active control system while requiring only a small fraction of the power. The study concludes that the semi-active control system based on MR dampers is a promising approach for seismic response reduction.