Abstract: A method of constructing a shaft in the earth for use as, for example, a launch shaft or a retrieval shaft, may include several steps. One step includes installing a secant pile wall into the earth. The secant pile wall encloses a portion of the earth. Another step includes excavating the portion of the earth enclosed by the secant pile wall. The excavated portion leaves an interior of the shaft and exposes an inside surface of the secant pile wall. Yet another step includes placing a metal liner within the interior of the shaft. And yet another step includes partially or more filling a space located between the inside surface of the secant pile wall and the metal liner with a grout material.

Abstract: A method of constructing a shaft in the earth for use as, for example, a launch shaft or a retrieval shaft, may include several steps. One step includes installing a secant pile wall into the earth. The secant pile wall encloses a portion of the earth. Another step includes excavating the portion of the earth enclosed by the secant pile wall. The excavated portion leaves an interior of the shaft and exposes an inside surface of the secant pile wall. Yet another step includes placing a metal liner within the interior of the shaft. And yet another step includes partially or more filling a space located between the inside surface of the secant pile wall and the metal liner with a grout material.

Abstract: A method of monitoring verticality of a sinking caisson having a tip. A pole is inserted into the earth to a pole depth substantially corresponding to a desired final depth of the caisson tip, one or more levels are coupled to the pole, and an elevation of the levels(s) is established. Scales are carried on an interior surface of the caisson in spaced circumferential locations and in reference to the caisson tip, and the level(s) is applied to the scales to indicate heights from the caisson tip corresponding to the circumferential locations of the scales. Tip elevations corresponding to the circumferential locations of the scales are determined by subtracting the indicated heights from the established elevation of the level(s). Any tilt of the caisson is calculated from any differences among the determined tip elevations.