What Does Barrel Joint Mean?
A barrel joint is a seal between the intersections of two barrels that are part of a manhole. A barrel is the bottom section of the utility access of a manhole. It has been found that improper barrel joints contribute greatly to inflow/ infiltration of water into the sewer system.
Trenchless technology offers many innovative rehabilitation methods such as chemical grouting to repair manholes without the need to break up the structure.
Trenchlesspedia Explains Barrel Joint
Barrel joints can be sealed using different methods such as chemical grout sealing, cementitious sealing, expanded gasket and manufactured manhole joint seal.
Chemical grouting is the most popular of these and is done from inside the manhole. The grout may be a single or two-part hydrophilic foam or gel, chemically activated gel or hydrophobic foam.
A pilot hole is drilled through the manhole wall and the grout is injected under pressure to reach the exterior cavity of the manhole. The grout then expands and seals the manhole from the outside effectively stopping inflow or infiltration of water through the joints. Barrel joints can also be sealed using flexible rubber seals that are compressed against the joints using expansion bands.