Devices, assemblies, and methods for shoring temporary surface excavations

An assembly for shoring temporary surface excavations, the assembly including:

• (a) a base unit including:
• (i) a base unit defining a base unit wall, the base unit wall extending in a height direction from a base unit lower edge to a base unit upper edge and defining a base unit central axis in the height direction, the base unit wall having a base unit wall inner surface and a base unit wall outer surface, the base unit wall inner surface defining a volume of the base unit and the base unit wall outer surface facing way from the volume of the base unit, wherein the base unit wall defines a barrier to the volume of the base unit in directions transverse to the height direction, and
• (ii) at least two jacking lugs mounted on the base unit within the volume of the base unit, each jacking lug including a jack receiver and a first jacking lug connection to the base unit wall inner surface, wherein the jack receiver is positioned to receive a jacking force applied in a direction from the base unit lower edge to the base unit upper edge, wherein the first jacking lug connection to the base unit wall inner surface is elongated in the height direction, and
• (iii) at least two lifting features mounted on the base unit, each lifting feature residing within the volume of the base unit and providing a lifting point adapted to accept a lifting force applied from above the base unit upper edge in the height direction, and
• (iv) a number of base unit upper connecting elements spaced apart about the base unit central axis;
• (b) a first extension unit including:
• (i) a first extension unit wall extending in the height direction from a first extension unit lower edge to a first extension unit upper edge and defining a first extension unit central axis extending in the height direction, the first extension unit wall also having a first extension unit wall inner surface defining a volume of the first extension unit and a first extension unit wall outer surface facing way from the volume of the first extension unit, wherein the first extension unit wall defines a barrier to the volume of the first extension unit in directions transverse to the height direction, and
• (ii) a number of first extension unit lower connecting elements spaced apart about the first extension unit central axis, each extension unit lower connecting element being aligned with and connected to a respective base unit upper connecting element of the base unit so that the base unit central axis approximately aligns with the first extension unit central axis;
• and
• (c) wherein the base unit wall outer surface aligns with the first extension unit wall outer surface so as to form a shoring surface that extends from the base unit lower edge to the first extension unit upper edge.

A method including:

• (a) placing at least two jacking devices within a volume of a shoring structure residing within an excavation with a lower edge of the shoring structure below a surface level, each jacking device being positioned in a respective operating position to apply a respective extraction jacking force to a respective jack receiver arrangement mounted on the shoring structure within the volume of the shoring structure, the respective extraction jacking force comprising a force applied to the respective jack receiver arrangement and sufficient to lift the respective jack receiver arrangement and shoring structure;
• (b) applying each respective extraction jacking force to the respective jack receiver arrangement to lift the shoring structure upwardly toward the surface level to a lifted position in which the lower edge of the shoring structure remains in the excavation below surface level;
• (c) after lifting the shoring structure to the lifted position, supporting the shoring structure against substantial movement in a downward direction away from the surface level, removing each jacking device from its respective operating position and filling in the excavation with fill material at least in an area below the lower edge of the shoring structure;
• and
• (d) removing the shoring structure from the excavation after filling in the excavation with fill material at least in the area below the lower edge of the shoring structure.