A pile press-in construction method uses a pile press-in device having a saddle, a clamp device grasping a top of an existing pile, a mast, a raising and lowering device, and a chuck device supported by the mast and holding a pile. The pile press-in device generates a reaction force by griping the existing pile with the clamp device, holds the pile by the chuck device, presses the pile into the ground by the raising and lowering device, and successively presses piles in while moving on a pile row including the existing pile to thereby extend the pile row. By turning of the mast and tilting of the chuck device about a chuck tilting axis, the chuck device is laid sideways and projects outward to a side of the pile row, the pile is supplied and inserted into the chuck device, and the chuck device grasps the pile.

A coupled shaft assembly for a foundation support system includes conical-shaped inner and outer couplers with mating helical ribs and grooves, and an anti-reverse element extending through different shaped openings in the inner and outer couplers that accommodates a limited degree of relative rotation of the couplers and thereafter precludes further relative rotation and an undesirable disengagement of the inner and outer couplers when subjected to reverse rotation.

A coupled shaft assembly for a foundation support system includes inner and outer couplers with mating helical ribs and grooves, and spring element that resiliently interlocks the inner and outer couplers in an axial direction. Built-in anti-reverse rotation elements in each coupler accommodates a limited degree of relative rotation of the couplers and thereafter precludes further relative rotation that could otherwise negatively impact the spring element and lead to an undesirable disengagement of the inner and outer couplers.

A pile connection comprises at least one fixture having a collar portion, a plurality of micropile sleeves, a plurality of gusset members extending between the collar portion and the micropile sleeves, and at least one connecting member that couples adjacent gusset members and that is spaced apart from the collar portion. A recess bounded by a wall of the collar portion is configured to contact a portion of a vertical pile. One or more fasteners may be used to press the wall against the vertical pile, with certain embodiments employing two complementary fixtures that may be coupled to one another (e.g., using the fasteners) along opposing sides of the vertical pile. Each micropile sleeve is configured to receive a micropile that may be driven through the sleeve into the ground at a position spaced apart from the vertical pile.

A coupled shaft assembly for a foundation support system includes conical-shaped inner and outer couplers with mating helical ribs and grooves, and an anti-reverse element extending through different shaped openings in the inner and outer couplers that accommodates a limited degree of relative rotation of the couplers and thereafter precludes further relative rotation and an undesirable disengagement of the inner and outer couplers when subjected to reverse rotation.