Owner: Louisville & Jefferson County Metro Sewer District
General Contractor: J.F. Shea Construction, Inc./Traylor Brothers
A launch shaft, pump station shaft and retrieval shaft were required for the ORT project in Louisville, Kentucky. With inside diameters ranging between 34’ and 49’, these access shafts were installed with overlapping secant piles extending a minimum 5’ into rock. The shafts extend deeper into rock to the final tunnel invert of up to 220’ below grade.
A series of overlapping, unreinforced secant piles were installed in a circular ring pattern to provide the lateral earth support for the shafts through the overburden soils and upper portion of the bedrock. Secant piles were installed up to a maximum of 113’ deep into the underlying bedrock which consisted of dolomitic limestone. The overburden consisted of a mixture of sands, silts and clays extending well below the water table. Verticality was checked on every secant pile to verify conformance with the design tolerance.