A main frame carries top and bottom shoring plates, with the top plates supported on pivoted brackets so that they can be tilted for leveling purposes. These brackets also can move transversely on vertically adjustable carrier bars to match the spacing between plates to the trench width. The shoring plates overlap each other when in raised position and are supported by cables connected to the bottom plates, which support the carrier bars. When the bottom plates are lowered, the top plates also can drop until the carrier bars strike a stop. Then the bottom plates continue to be lowered until striking a further stop. The main frame is supported on driven, independently steered wheels that can be shifted between various lateral spacings to keep weight away from the sides of a trench.

This shoring system enters in the category of slide rail shoring systems, including rails, panels and strutting assemblies. It applies on shoring of excavations of various shapes such as trenches, rectangular and polygonal pits of great or lesser depth. Rails are of two types, linear or corner rails. Pairs of linear rails are spaced apart along excavation so that a strutting assembly keeps opposite rails of a pair of rails pressing against wall of excavation; corner rails are placed on the corners of any polygonal shaped excavation. Shoring panels slide vertically between adjacent rails creating a shoring wall on two or more sides of excavation. Rails have opposite sides provided with an outer and an inner guide for sliding vertically panels. The outer guide runs the full length of rail while inner guide is halfway from the bottom up reducing the weight of rail and easing installation and removal of panels. The corner rails are adopted to shore pits of polygonal shape of four or more corners eliminating the need of cumbersome strutting assemblies inside excavation. Linear rails have frontally an external edge guide so that at least one strutting assembly slides interlocked between two oppositely held linear rails. The strutting assembly has a horizontal spreader and two vertical members and is modulable by mean that two or more of them could be assembled together using vertical extension members. Strutting assembly is provided with rollers to ease its vertical mobility. Shoring panels are of equal design and access the rail laterally by swinging within outer and inner guides.

This apparatus relates to shoring of deep excavations such as pits or trenches. It includes vertical rail posts arranged symmetrically in pairs which are spaced form each other along the excavation, articulated trusses holding opposite rail posts against each other and large shoring panels sliding between adjacent rail posts on either side of the excavation. Each rail post has on either side one channel of stepped cross section guiding vertically two or more shoring panels. The connections between the post and the panel are partially or completely open. The open connections are performed by magnetic forces engendered by thin magnetic flat bars incorporated in the posts or the panels in the area of their contact. The articulated truss is of scissoring type composed of triangular cells only and their members have pinned connections. The cross members of the truss are pinned together in their mi-length enabling their relative rotation while their extremities are pinned into the vertical members which have several row of pinning holes in order to adjust the width of the trench without need for additional spreaders. The vertical members of the truss slide formlockingly between pair of opposite posts and could be adjusted at any level form the bottom of excavation.

This invention discloses a device for shoring open excavations including a pair of shoring panels held vertically apart and parallel to each other against sidewalls of excavation by a pair of strutting assemblies. Each shoring panel having laterally on either end a vertical guide of circular cross section and lengthwise two identical cutting edges of triangular cross section, which are inversely arranged one on the top and the other at the bottom of panel and reverse relative to sidewall of excavation as well. Each strutting assembly has a pair of vertical struts held against each other by at least one horizontal strut that is fastened by pin or bolts onto vertical supports. Each vertical strut is provided with a circular guide channel encompassing the guide of shoring panel and interlocking with it, so that shoring panels slide independently from each other, while the strutting assembly can adjust different pipe culverts.

This apparatus relates to shoring of deep excavations such as pits or trenches. It includes vertical rail posts arranged symmetrically in pairs that are spaced from each other along the excavation, articulated trusses and/or spreaders holding opposite rail posts against each other and large shoring panels sliding between adjacent rail posts on either side of the excavation. Each rail post has on either side one channel of a stepped or non-stepped cross section guiding vertically two or more shoring panels. In one variation, the inner and outer panel guides on one side of the vertical rail post reside in the same vertical plane. The connections between the rail post and the wall panels are partially or completely open. The open connections may be performed by magnetic forces arising from thin magnetic flat bars incorporated in the posts or the panels in the area of their contact. The articulated truss may be of a scissoring type and may be composed of triangular cells only and their members may have pinned connections. The cross members of the truss are pinned together in their mid-length enabling their relative rotation while their extremities are pinned into vertical members which have several rows of pinning holes in order to adjust the width of the trench without the need for additional spreaders. The vertical members of the truss slide formlockingly between a pair of opposite posts and could be adjusted at any level from the bottom of excavation. The truss may also include one or more rollers that facilitate its vertical mobility.