Precast concrete facing panels are the most common of facing elements used in MSE wall construction along highways. RECo’s concrete panels employ a lap joint on all horizontal and vertical joints, whereby panel-to-panel contact is avoided and flexibility of the facing is assured.
This flexibility is maintained by specially fabricated elastomeric bearing pads that support the panel above while preventing contact between the two panels. This detail allows the panels to be adjusted horizontally during installation as well as move vertically in the event of differential settlement or seismic occurrence. The joint dimensions allow some panel rotation thereby allowing a wall to follow the profile of different settlements.
In addition to flexibility, the panel joints are an important part of the wall system. Lap joints provide an indirect flow path for water in the event that the primary drainage system is inadequate for the event.
Lap joints also shield the filter fabric on the fill side of the joint from direct exposure to degrading UV rays. The lap joint also provides protection of the fabric from damage by vandals and animals.
A nominal joint width of 20mm (3/4″) has been used by RECO for over 30 years. This joint dimension has become an industry standard recognized in numerous state and country codes.
Lap joints are a sophisticated precast panel feature with many advantages. RECO strongly recommends that Owners, Engineers, and Contractors specify 20mm (3/4″) lap joints for their MSE wall projects.