Joint Failure Not Always Obvious--Test Every Joint
I visited a job site a few weeks ago and talked with the grouting operator. I found three things very cool:
- It was nice to visit a grout truck that was kept clean and orderly. This was a municipality that only has one crew responsible for each grout truck, so they treat it like their own.
- They air tested every joint. There is no point in grouting only the visible leaking joints and ignoring the ones that are not noticeable. The joints must pass an air test or should otherwise be grouted. If not, once you grout the leaking joints, the groundwater simply migrates to the next joint and enters there.
- Looking into the manhole, it was very apparent that the line they were grouting had a lot of infiltration (leaks) as the water flowing through the bottom of the manhole was clear and not murky from sewage.