The trench shoring apparatus includes first and second side panels connected in a parallel spaced-apart configuration by a connecting rod pivotally connected to one end of one or more pairs of lateral arms. The other opposite end of the one or more pairs of lateral arms is hingedly connected to the side panels, such that translational movement of the connecting rod in a direction parallel to the side panels causes the spaced-apart panels to move between retracted and extended parallel spaced-apart configurations.

A ring-shaped cofferdam and temporary pit excavation structure using tapered square pipes includes a plurality of tapered square pipes a trapezoidal cross-section, in which the plurality of tapered square pipes each have a coupling protrusion or a coupling groove formed in a longitudinal direction on a first side, the plurality of tapered square pipes each have a coupling protrusion or a coupling groove formed in the longitudinal direction on a second side, the plurality of tapered square pipes are assembled by coupling the coupling protrusions and the coupling grooves, a long side of two parallel sides of the trapezoid is disposed outside, and a short side is disposed inside.

A subgrade with local deep excavation and backfilling structure and a rapid construction method thereof are provided. Supporting cast-in-place piles are laid at positions where an underground pipe gallery is located in a subgrade structure, and soil there between are longitudinally excavated to form a line-shaped foundation pit. A bottom of the line-shaped deep foundation pit is reinforced to support the underground pipe gallery, and lateral peripheral regions and top peripheral regions of the underground pipe gallery are backfilled with block geobag reinforced fillers. Geogrids are placed on the top of the underground pipe gallery, then backfilling compaction and reinforcing are performed, and the geogrids are fixedly assembled with anchor bolts. The construction method is simple and easy. By using compacted block geobag reinforced fillers and cement solidified slurry, an overall quality of the subgrade structure after backfilling can be ensured, and construction period and cost can be greatly reduced.

A subgrade with local deep excavation and backfilling structure and a rapid construction method thereof are provided. Supporting cast-in-place piles are laid at positions where an underground pipe gallery is located in a subgrade structure, and soil there between are longitudinally excavated to form a line-shaped foundation pit. A bottom of the line-shaped deep foundation pit is reinforced to support the underground pipe gallery, and lateral peripheral regions and top peripheral regions of the underground pipe gallery are backfilled with block geobag reinforced fillers. Geogrids are placed on the top of the underground pipe gallery, then backfilling compaction and reinforcing are performed, and the geogrids are fixedly assembled with anchor bolts. The construction method is simple and easy. By using compacted block geobag reinforced fillers and cement solidified slurry, an overall quality of the subgrade structure after backfilling can be ensured, and construction period and cost can be greatly reduced.

The method is used for strutting brace legs in a quadrangular setup of a rim of brace legs. The method consists in that a spreader (3) is attached to one end of each brace leg (2), while an extendable tensioning unit (4) is attached to the other end of the same brace leg (2). Next, the brace legs (2) are set inside the excavation in such a manner that, in the excavation corners, the ends of the brace legs (2) terminated with spreaders (3) become coupled with the ends of the subsequent brace legs (2) terminated with tensioning units. Once all the brace legs (2) have been coupled with each other, the ends of the brace legs (2), with the spreaders (3) attached to them, are pressed against the sheet piles (1) in the excavation corners by means of tensioning units (4) attached to subsequent brace legs (2).

An apparatus for removable insertion into an excavated trench to protect a worker against collapse of the trench wall, which is often termed in industry as a trench shield or cage or box, comprises cross members interconnecting opposite sides of a protective peripheral wall that are in the form of rounded annuluses. Additional members are provided to interconnect adjacent pairs of annuli which are spaced one from the other in a height direction of the wall. This forms an interconnected internal frame of the apparatus which primarily provides compressive strength of the apparatus against collapsing of the trench wall instead of the protective wall so that the protective wall may be made to be lighter in terms of mass. Further, the protective peripheral wall forms a tube substantially fully enclosing a working area defined by the wall.

An apparatus for removable insertion into an excavated trench to protect a worker against collapse of the trench wall, which is often termed in industry as a trench shield or cage or box, comprises cross members interconnecting opposite sides of a protective peripheral wall that are in the form of rounded annuluses. Additional members are provided to interconnect adjacent pairs of annuli which are spaced one from the other in a height direction of the wall. This forms an interconnected internal frame of the apparatus which primarily provides compressive strength of the apparatus against collapsing of the trench wall instead of the protective wall so that the protective wall may be made to be lighter in terms of mass. Further, the protective peripheral wall forms a tube substantially fully enclosing a working area defined by the wall.

The trench shoring apparatus includes first and second side panels connected in a parallel spaced-apart configuration by a connecting bar pivotally connected to one end of one or more pairs of lateral arms. The other opposite end of the one or more pairs of lateral arms are hingedly connected to the side panels, such that translational movement of the connecting bar in a direction parallel to the side panels causes the spaced-apart panels to move between retracted and extended parallel spaced-apart configurations. There is a lock for releasably restricting translational movement of the connecting bar.

The trench shoring apparatus includes first and second side panels connected in a parallel spaced-apart configuration by a connecting bar pivotally connected to one end of one or more pairs of lateral arms. The other opposite end of the one or more pairs of lateral arms are hingedly connected to the side panels, such that translational movement of the connecting bar in a direction parallel to the side panels causes the spaced-apart panels to move between retracted and extended parallel spaced-apart configurations. There is a lock for releasably restricting translational movement of the connecting bar.

A trench box which has first and second side panels connected in parallel spaced relation by first and second lateral supports. Each lateral support comprises connection points at each end of each lateral support that connect the side panels to the lateral supports. The connection points maintain the side panels in parallel spaced relation and the lateral supports in parallel spaced relation between the side panels. Each connection point comprises a pivot connection that permits pivotal movement of the side panels relative to the lateral supports about a pivot axis, and a releasable connection spaced from the pivot connection in a direction perpendicular to the pivot axis. The releasable connection is selectively releasable to permit the respective first or second side panel to pivot about the pivot axis such that the panels are not parallel.