An active air injection system is required by the city's Building and Safety Code for areas with reported high methane concentrations as well as passive venting and enhanced ventilation. The system consists of 2.5 inch air injection piping that is between the 4 inch passive vent pipes, and there...
Thanks guys for the answers. I also looked into the literature on trenchless technology where they use compressed air to stabilize the face and prevent groundwater intrusion into the pipe. However, most of the research involves two phase flow because most of the pipes are placed below the water...
You're absolutely right! The way the system works is that if the methane concentrations in the subslab space exceed a threshold concentration, as monitored by sensors in the compacted sand, the air injection system will be triggered which flushes the methane toward the passive vent piping, where...
Thanks for the response. The concern was with the external sand bed and the displacement of sand away from the pipe with the velocity of air coming out of the slots, thus creating pockets where the methane gas could accumulate. I agree with you that the system is fluid and if any sand was...
I've got a project where we're installing 2.5 inch PVC slotted pipe in 4 inches of 90% compacted sand beneath a concrete slab as part of an air sweep system for methane mitigation. One of the reviewers of the system design asked if it would be possible to displace the compacted sand at a given...