A Review of Link Slab Material Selection, Design, and Construction

Link slabs have emerged as an effective alternative to traditional expansion joints in bridge systems, helping mitigate durability issues associated with water infiltration and joint deterioration. Expansion joints accelerate the degradation of bridge superstructures due to water infiltration and inadequate drainage. The use of link slabs eliminates expansion joints, creating a continuous deck while maintaining simply supported boundary conditions. In this paper, a systematic and critical review of link slabs is presented, synthesizing more than two decades of research on structural behavior, material selection, design methodologies, and life cycle performance. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses–based methodology was used to identify and evaluate key studies, enabling a structured assessment of trends and knowledge gaps. Link slab behavior has been verified through field testing, experimental testing, and numerical modeling. Researchers have investigated the use of engineered cementitious composite and ultrahigh-performance concrete (UHPC) as alternatives to traditional concrete and have found favorable results. Similarly, fiber-reinforced polymer is an acceptable alternative to steel reinforcement. Fatigue, freeze–thaw, and seismic behavior are also examined. Life cycle analyses show economic benefits in addition to the documented structural benefits, including increased service life for bridge bearings and the superstructure. This review identifies critical gaps, particularly the lack of long-term in situ performance data and limited field validation of emerging materials such as UHPC. Future research is proposed, with an emphasis on field monitoring, fatigue characterization, and material optimization. The findings will provide insights for bridge engineers and agencies seeking to implement durable jointless bridge systems.