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Buckling-restrained braces (BRBs) are widely used to improve the seismic performance of buildings. This paper aims to introduce BRBs to suspension bridges and assess the seismic performance of bridges with BRBs. Taking the Dadu River Bridge as a case study, an FEA model of the bridge is established, and different seismic measures (BRBs between the deck and the tower, BRBs at the middle of the span to replace the inclined suspenders to connect the deck and the main cables, fluid viscous dampers (FVDs) between the deck and the tower, the combination of BRBs to replace the inclined suspenders as well as FVDs between the deck and the tower) are applied to the suspension bridge. The influence of the parameters of BRBs on the seismic response of the suspension bridge is studied, and the performance of the bridge with BRBs is compared with that of the bridge with FVDs. The results indicate that the use of BRBs in place of the inclined suspenders is beneficial to reduce the displacement of the deck and limit the shear force and bending moment of the tower. The seismic performance of the suspension bridge with BRBs and FVDs is better than that of the bridge with BRBs or FVDs. Therefore, the application of BRBs is a feasible method to improve the seismic performance of the suspension bridge. [ABSTRACT FROM AUTHOR]

A new remediation technique is proposed to mitigate large deformations imposed on buried pipeline systems subject to permanent ground deformation. With this technique, low-density gravel (LDG) with high porosity, such as pumice, is used as backfill in the trench containing the pipe near an area susceptible to PGD. This countermeasure decreases soil resistance, soil-pipe interaction forces and strain on the pipe as the pipeline deformation mechanism changes to a more desirable shape. Expanded polystyrene geofoam has been introduced to decrease the density of the pipeline backfill; however, LDG is more efficient regarding workability during construction, environmental effects, durability, fire safety, and cost-effectiveness. A series of centrifuge model experiments in which the pipelines were subjected to reverse faulting was conducted to evaluate the proposed method. During faulting, the axial and bending strain and pipe deflection were measured. A comparison of the responses of the remediated pipeline and the pipeline without remediation indicates that the proposed technique substantially mitigates the effects of large deformation. [ABSTRACT FROM AUTHOR]