LAUNCH PITS
A drilling contractor was installing a new sewer line for the City of Atlanta. The launch pit for the jacking equipment was installed to approximately 25’ below grade. After the equipment was set in place, the initial launch attempt found that existing soils surrounding the launch pit were not stable enough to handle the extreme pressures exerted by the Tunnel Boring Machine.

Barton Southern Company was called in to stabilize the disturbed soil. Injection probes were driven horizontally to a distance of 14’ from the edge of the launch pit. A hydrophobic polyurethane resin was injected into the soil as the probes were pulled back into the pit. The loose soil was stabilized and the subsequent launch was successful.

As trenchless technology projects continue to multiply, engineers and contractors are finding that Barton Southern can help solve a multitude of problems caused by poor soil or excessive water conditions.

SEAWALLS
In Sarasota, FL, a swimming pool and spa just a few feet from the edge of a seawall in a waterfront neighborhood were sinking. Water from the bay was leaking in through joints in the seawall, eroding the sandy soil under and around the pool causing cracks to develop and water to leak out of the pool. The contractor had heard that soil stabilization with polyurethane chemical grout could solve such problems, and called Barton Southern to perform the work.

Crews injected a hydrophobic grout, that when injected into the wet, sandy soils, expanded and solidified to stabilize the soil under the pool. This injection process pushed water out of the sand then filled the micro voids between particles of sand to form a cohesive mass of solidified soil and grout under the pool. Other holes were drilled in a grid pattern, and the injection process repeated to completely encapsulate the underside of the pool.
To stop the inflow of water through the seawall, Barton Southern crews injected a “grout curtain”, or waterproof barrier behind the seawall to stop water intrusion. Repair crews knew that they had sufficient penetration when injected grout was seen exiting from cracks in the seawall on the bay side. In just under a week, the pool, spa, and seawall were completely stabilized.