Slip joints are vertical divisions that run from the top (cope level) to the bottom (toe level) of blockwork seawalls. They are engineered to accommodate potential differential settlements between neighboring seawall panels. Within these joints, half-round channels filled with aggregates enable vertical movement caused by uneven settling. Simultaneously, the aggregates provide interlocking forces that bind the adjacent panels together, acting as a unified structure to resist lateral earth pressure.
Additionally, slip joints serve as pressure relief valves for built-up water pressure and permit lateral movement, such as contraction caused by seasonal variations. This dual functionality enhances the seawall’s resilience by mitigating the risks associated with differential settlement and internal pressure, ultimately contributing to its long-term stability and performance.