Grouted sleeve connections are widely employed in the substructures of prefabricated bridges. After installation, the grout filling condition inside the sleeves cannot be directly inspected, while grouting defects may significantly compromise the mechanical performance of the piers. This study investigates the feasibility of using the non-destructive impact-echo method to detect grouting defects in sleeves. Finite element simulation was conducted to analyze the influence of the distance between the impact point and the signal acquisition point on detection accuracy, revealing that a distance of 40–60 mm yields optimal results. Experimental findings demonstrate that the method can effectively identify grouting defects in double-row sleeves, although it cannot precisely locate the defective sleeve. A novel analytical approach is proposed, using the thickness frequency and its modes of fully grouted specimens as a benchmark. By comparing thickness frequencies at different measurement points, grout quality can be intuitively evaluated. Validation using a six-sleeve model with varying grouting densities confirmed the method’s effectiveness in detecting grouting defects in non-boundary sleeves and its practical applicability in engineering.

This paper reviews the current state of research on the seismic behavior of precast segmental bridge piers, systematically elucidating their performance under different connection configurations in the context of accelerated bridge construction and resilience demands. Additionally, it compiles commonly used research methodologies and strategies for enhancing seismic performance. The evidence indicates that emulative precast segmental piers can closely match monolithic cast-in-place structures, with reported peak lateral strengths typically within about 10% and comparable yield and peak displacements, whereas non-emulative systems generally provide superior self-centering with smaller residual displacements. Experimental studies, theoretical analyses, and numerical simulations have all proven effective in characterizing the mechanical behavior of these piers; each approach has distinct advantages, and a synergistic integration of methods is recommended for comprehensive evaluation. Measurable improvements in seismic performance have been reported through hybrid connection systems, innovative detailing, supplementary energy-dissipating devices, and the use of high-performance materials such as ultra-high-performance concrete (UHPC), engineered cementitious composites (ECC), fiber-reinforced polymers (FRP), and shape memory alloys (SMA); for example, representative tests reported about a 30% increase in energy dissipation at drift ratios exceeding 3%, and SMA-based reinforcement has been reported to reduce residual drift by roughly 67% relative to steel reinforcement. Finally, future research directions are proposed to support the wider adoption of precast bridge piers in high-seismicity regions, including addressing challenges related to performance degradation under multi-hazard coupling conditions, insufficient design criteria for connections, and the need for rapid post-earthquake repair and resilience.