GB2593204A

GB2593204A - Trench access apparatus

Info

Publication number: GB2593204A
Application number: GB2004004.4A
Authority: GB
Inventors: Smith Stuart
Original assignee: AQUA FABRICATIONS Ltd
Current assignee: AQUA FABRICATIONS Ltd
Priority date: 2020-03-19
Filing date: 2020-03-19
Publication date: 2021-09-22
Also published as: GB202004004D0

Abstract

Trench access apparatus 10 arranged for location within a trench, and comprising: a pair of opposed first walls 12, 14; a pair of opposed second walls 16, 18; the walls being connected so as to define a trench access space of substantially rectangular lateral cross-section and upper regions of the walls defining a trench access opening being arranged to allow for passage into the trench access space; and wherein a lower region of at least one wall includes a recess formation 20 arranged to straddle equipment exposed within the trench. A method of using the apparatus to provide access to a trench. The recess may be formed on opposing walls, the equipment may be pipework. There may also be a travel formation formed on the bottom of the apparatus which may be a skid 24, 26.

Description

TRENCH ACCESS APPARATUS

The present invention relates to trench access apparatus, and to a method of allowing and maintaining safe access for operatives into, and within, a trench.

Openings into the ground to form trenches, ditches, holes etc., collectively referred to herein simply as a trench, are commonly provided to allow for the locating and/or maintenance, inspection and repair, of subsurface apparatus and equipment, or sometimes simply for subsurface storage.

In many instances, the depth of the trench, and thus height of the trench walls from the trench floor, can exceed the average height of personnel likely to be working within the trench. There is therefore an inherent danger arising from the potential instability of the trench walls, and the possibility of trench collapse particularly since the integrity of the trench walls can be greatly affected by variable such as depth, wall angle, local geology and conditions such as the extent of saturation of the earth within which the trench is formed.

To provide for the protection of personnel working within a trench environment therefore it is known to provide an earth retaining structure which abuts against the trench walls seeking to prevent collapse, even in situations where the trench walls are near vertical.

However, such known earth retaining structures are fitted in situ' after the trench has been dug and so the operatives installing the earth retaining structure remain exposed to the possibility of trench wall collapse while fitting the earth retaining structures. The known earth retaining structures comprise flat wall panels located against respective opposite side walls of the trench, and retained in position, and urged against the trench walls, against which each abuts, by way of hydraulic rams.

The deployment of such an earth retaining structure is therefore a relatively time-consuming and complex procedure requiring manual positioning of the wall panels and then the subsequent positioning and adaption of the hydraulic rams to urge the wall panels against the respective trench walls. While the time taken to construct and configure such an earth retaining structure disadvantageously delays the required eventual access into the trench, it also disadvantageously creates a restricted working environment within the trench in so far as the personnel will have to work around, and to some extent be obstructed by, the hydraulic rams which extend across the width of the trench. Yet further, such hydraulic rams can also be prone to failure, most usually through leakage of the hydraulic system, and so regular maintenance and/or at least safety checks are required to ensure the integrity of the earth retaining structure, and the ongoing safe down-trench working environment for the personnel.

Also, once access by personnel to the trench is no longer required, and the trench is to be refilled, the known earth retaining structures have to be removed by a procedure which is the reverse of that at the time of forming the structures in situ. This necessarily involves the time-consuming removal of hydraulic rams to allow for subsequent removal of the wall panels, and disadvantageously all at a time while personnel are within the trench and so again exposed to potential trench collapse. The use of hydraulic rams can also provide for undesired electrical conductivity of the overall structure.

The present invention therefore seeks to provide trench access apparatus having advantages over known such apparatus, and also to provide for an improved method of facilitating trench access in a manner providing and maintaining safe down-trench conditions for personnel.

According to one aspect of the present invention there is provided trench access apparatus arranged for location within a trench, and comprising a pair of opposed first walls, a pair of opposed second walls, the walls being connected so as to define a trench access space of substantially rectangular lateral cross-section and upper regions of the walls defining a trench access opening being arranged to allow for passage into the trench access space, and wherein a lower region of at least one wall includes a recess formation arranged to straddle equipment exposed within the trench.

The invention is advantageous in that it can provide a reliable safe, secure and stable working environment within a trench. The opposed pairs of walls in particular provide advantageously effective protection against trench wall collapse. The structure of the apparatus also advantageously lends itself to easy and accurate location within, and removal from a trench.

In particular, the present invention proves advantageous in so far as its relatively simple, yet structurally sound configurations negates the requirement for, and use of, hydraulic rams such as those found within the prior art. It can therefore advantageously provide a simple and robust earth-retaining structure providing improved safety for personnel whilst working in a trench environment.

Whatever the requirement for forming, and allowing access into, a trench, the present invention advantageously allows quick and easy ingress and egress of the trench for example to allow for pipe and/or cable inspection and maintenance, or to fix further equipment such as couplers or to check and adjust pipe levels.

The apparatus of the invention can be quickly and accurately located within the trench. If required, the apparatus can be mechanically lowered into its required position within the trench without the requirement for personnel within the trench. Trench access by such required personnel is then not necessary until such time as the apparatus is in situ, thereby maximising the safety of the personnel required to work within the trench. The apparatus simply requires location within the trench and there is no need for, nor indeed no real possibility of, abutting the walls of the apparatus in a compressive manner against the trench walls. Installation of the apparatus of the invention is therefore a much easier, less dangerous and far quicker exercise as compared with the prior art.

Further, the said recess formation assists in allowing access to sub-surface equipment revealed within the trench, while allowing for stable and secure footing of the apparatus on the surface of the trench floor.

In particular, the lower regions of at least the opposed first walls can each include a recess formation arranged for straddling equipment exposed within the trench, and so as to further assist with stable footing of the apparatus on the trench floor. Such stability can be further enhanced by the recess formation of one first wall being located and aligned and opposite the recess formation of the other said first wall.

If required, the said recess formations can be of the same size and shape, or alternatively of different size and/or shape.

Advantageously, the said access opening is of substantially rectangular cross-section, which if required can match the shape and dimension of the trench access space.

In one particular aspect, the said recess formation can be arranged to straddle pipework.

Depending upon the characteristics of the said pipework, such as for example shape and configuration, or access requirements, the said recess formation can comprise a rectilinear recess.

To further enhance its structural rigidity, each side wall of the apparatus can be formed integral with its neighbour. In this manner, the apparatus can be formed as a single piece unit.

To assist with its adaptability for use with trenches of differing depth, at least one wall of the apparatus can be arranged to receive a wall extension panel to increase the height of the apparatus in the region of the said at least one wall.

Preferably, the said wall extension panel can comprise a wall extension unit having a pair of opposed first walls and a pair of opposed second walls arranged to extend upwardly from the respective first and second walls of the apparatus.

Advantageously, the apparatus can be provided in modular form comprising the said opposed first and second walls, and at least a first wall extension unit.

As a further feature, the bottom of at least one pair of opposed walls of the apparatus can be provided with at least one travel formation arranged to assist with movement of the apparatus along the surface of the trench floor.

Advantageously the said travel formation can comprise a skid/ski, or a pair of skids/skis.

Yet further, the apparatus can include engagement formations for assisting with manipulation and movement of the apparatus within, into or out of the trench.

Particular advantages as regards strength and weight can be achieved through formation of the apparatus from GRP. Advantageously the apparatus is also then non-conductive.

According to yet a further aspect of the present invention, there is provided a method of securing a trench for access to equipment exposed within the trench, and comprising lowering apparatus according to any one of more of the features noted above into the trench to straddle the equipment and provide a trench access space for access to the equipment.

It will be apparent that various further advantages arise from the present invention particularly in so far as it can be readily formed from nonconductive material, such as GRP, and it can allow excavation sides of a trench to be cut vertical or at least near vertical. The apparatus can be formed as a one-piece unit or if required a modular unit, and can therefore be provided to any length, width and depth that might be required so as to meet any specific known trench dimension requirements.

In one particular aspect the apparatus of the invention comprises a box-like structure, open at the top and bottom.

The invention is described further hereinafter by way of example only with reference to the accompanying drawings in which: Fig. 1 is a perspective view of trench access apparatus according to an embodiment of the present invention; Fig. 2 is a side view of apparatus such as that of Fig.1 but with additional fixtures and fittings included; Fig. 3 is a plan view of the apparatus of Fig. 2; Fig. 4 is an end view of the apparatus of Fig. 2; and Fig. 5 is a partial end view of a further adaption of the apparatus of Fig. 2.

Turning first to Fig. 1, there is provided a perspective view of trench access apparatus 10 according to an embodiment of the present invention and comprising a large box type structure formed of opposite side walls 12, 14 and opposite end walls 16, 18. The structure can be formed in any particular manner and the present invention is not restricted in this regard. That is, the apparatus 10 can be formed as a single integral unit or formed from two or more walls which are required to be connected together to arrive at the structure illustrated in Fig. 1.

The box type structure is arranged and configured to be of a size and depth suitable to the trench in which it is to be located, and suitable to allow for access to, and easy movement within, the trench by personnel.

The end walls 16, 18 of the structure have recesses 20 (only one of which is visible in relation to end wall 16) and which are arranged to provide openings 22 (again only one of which is visible) to allow for the structure to straddle equipment/apparatus to be revealed within the trench and requiring access by the personnel.

In the particular embodiment illustrated with reference to Fig. 1, each undersurface of each side wall 1214 is provided with an elongate ski structures 24, 26, with respective upturned ski tips 24A, 24B; 26A, 26B at each end. These ski structures 24, 26 serve to allow for ease of movement of the apparatus 10 along a trench floor once in situ within a trench. Once initially in place therefore within the trench, the apparatus 10 can readily be moved along the direction of the trench simply as the trench is cut on an ongoing basis and thereby vastly reducing delays and downtime as can be encountered in the prior art.

Fig. 2 provides a side view of the apparatus of Fig. 10 in a direction facing the side wall 12 and further illustrates the particular configuration of the ski structure 24 located beneath the side wall 12.

As illustrated by Fig. 2, the apparatus 10 of Fig. 1 can be provided with further fixtures and fittings as required and allowing for ready, and ideally mechanical, movement and manipulation of the apparatus; and also to accommodate a required change in its effective height/depth.

That is, and merely as examples, annular lifting points 28 can be provided extending from the surfaces of the end walls 16, 18 of the apparatus so as to allow for lifting/lowering of the apparatus as required. In the illustrative examples, the lifting points can be fitted with a carabiner-locking screw-gate.

In addition, the upper region of each of the side walls 12, 14 and end walls 16, 18 can be provided with toggle latch clamps 30, which are arranged to latch onto appropriate formations on extension wall elements (described later in relation to Fig. 5) so as to increase the height/depth of the box structure.

Fig. 3 is a plan view of the apparatus 10 as illustrated in Fig. 2 and showing the same fixtures and fittings 28, 30. Fig. 3 illustrates how these fixtures and fittings 28, 30 can be spaced around the outer surfaces of box structure walls 12, 14, 16, 18. However, it should be appreciated that the illustrated type, number, location and spacing of such fixtures and fittings is in no way limited to the illustrated example. Such fittings can be provided in any required number, and at any required location, appropriate to the requirement for movement of, and/or extension of, the dimensions of the boxlike structure.

Turning now to Fig. 4, there is illustrated by way of an end view of the apparatus 10 a further representation of the opening 22 defined by the recess 20 formed in the lower region of the end walls 16, 18. Although only one opening 22 in the end wall 16 is immediately apparent within Figs. 1 and 4, there is also in the illustrated embodiment an aligned opening within end wall 18, and having the same dimensions as the opening 22 in the end wall 16.

It should have a be appreciated that the openings in the end walls can be provided in any particular shape and/or configuration and need not be aligned nor of identical, or indeed near similar, shape and configuration. Indeed, if required, only one end wall need be provided with such an opening.

In any case however, the opening in the end wall is arranged to provide for a recess formation of any required shape and configuration that is arranged to straddle equipment to be revealed through excavation of a trench. A wide variety of such equipment is likely to be revealed through trench excavation and so, accordingly, a wide variety of recess formations can be provided. As a particular feature however, the recess formation can advantageously be configured so as to fully straddle the equipment such that the undersurface of the apparatus 10, that is in the illustrated example the skis 24, 26, achieve secure footing on the trench floor.

In situations however where the equipment to be revealed through the trench excavation, and to be accessible to personnel within the trench, comprises longitudinally extending equipment such as cabling or pipework, the straddling of the pipework by way of openings provided in both end walls 16, 18 can prove particularly advantageous. That is, such straddling by way of openings in both end walls allows for movement of the apparatus 10 in situ within the trench environment and along the length of the cabling or pipework as required. It will of course be appreciated that such ease of movement is further facilitated by way of the respective ski structures 26, 26.

Turning now to Fig. 5, there is provided a partial end view of end wall 16 of the apparatus 10 with its fixtures and fittings 28, 30. Located on top of the apparatus 10 is a box extension structure 36 having lateral and longitudinal dimensions matching those defined by the walls 12, 14, 16, 18 of the apparatus 10. The lateral and longitudinal dimensions of the box extension structure 36 therefore match the apparatus 10 with sufficient tolerance to allow for matching of the toggle latch clamps 30 of the side and end walls 12, 14 and 16, 18 with appropriate respective formations on the outer surfaces of the side and end walls of the box extension structure 36.

As illustrated in Fig. 5, the box extension structure 36 can itself be provided with engagement formations such as further lifting Fig. 5 points 34 so as to assist with the lowering/raising of the box extension structure 36 relative to the apparatus 10, particularly while the apparatus 10 is in situ within a trench.

As therefore will be appreciated through reference to Fig. 5, the effective height/depth of the apparatus 10 can be varied as required, and on-site, so as to be readily responsive to different trench dimensional requirements.

Although not illustrated in the accompanying drawings further fixtures and fittings can be provided, particularly so as to allow for easy entry into, and exit from, the trench environment for relevant personnel. That is, access handles or poles can be provided and step irons or other similar formations be provided on the inner surface of at least one of the walls of the apparatus so as to allow for ease of entry/exit for personnel. The engagements such as the lifting point attachments illustrated advantageously enable the apparatus 10 to be moved along the trench and into and out of, the trench in a relatively simple and safe manner by way of relatively light plant machinery.

The provision of the apparatus as fixed width sections advantageously enables quick and easy installation without the need to adjust or pre-set the box structure's width.

It should be appreciated that the invention is not limited to the details of the foregoing specific embodiment. That is, the box type structure can be formed from walls of any appropriate material, and to any particular dimension such that the overall apparatus can exhibit any appropriate footprint as required.

Also, the undersurface of the apparatus need not be configured to assist with movement along the trench floor, but could alternatively come in addition, be provided with anchoring formations serving to secure the apparatus against movement along the trench floor.

As also noted previously, the recess formation(s) can be provided in any particular number, in relation to any particular wall, and of any particular shape/configuration. Such shape/configuration can be arranged to match closely particularly the sectional shape configuration of apparatus to be revealed within the trench, alternatively can be provided with dimensions large enough to straddle a wide variety of equipment to be potentially revealed through the trench excavation.

Claims

CLAIMS1 Trench access apparatus arranged for location within a trench, and comprising: a pair of opposed first walls; a pair of opposed second walls; the walls being connected so as to define a trench access space of substantially rectangular lateral cross-section and upper regions of the walls defining a trench access opening being arranged to allow for passage into the trench access space; and wherein a lower region of at least one wall includes a recess formation arranged to straddle equipment exposed within the trench.
2. Trench access apparatus as claimed in Claim 1, wherein the said trench access opening is of substantially rectangular cross-section.
3. Trench access apparatus as claimed in Claim 1 or 2, wherein the lower regions of at least the opposed first walls each include a recess formation arranged for straddling equipment exposed within the trench.
4. Trench access apparatus as claimed in Claim 3, wherein the recess formation of one first wall is located aligned and opposite the recess formation of the other said first wall Trench access apparatus as claimed in Claim 1, 2, 3 or 4, wherein the recess formations are of the same size and shape.6 Trench access apparatus as claimed in Claim 1, 2, 3 or 4 wherein the recess formations are of different size and/or shape.7. Trench access apparatus as claimed in any one or more of the preceding claims, wherein the first walls comprise end walls of t he apparatus.8. Trench access apparatus as claimed in any one or more of the preceding claims, wherein the second walls comprise side walls of the apparatus.9. Trench access apparatus as claimed in any one or more of the preceding claims, wherein the said side walls are arranged for location adjacent side walls of the trench.10. Trench access apparatus as claimed in any one or more of the preceding claims, wherein the recess formation is arranged to straddle pipework.11. Trench access apparatus as claimed in any one or more of the preceding claims, wherein the recess formation comprises a rectilinear recess.12. Trench access apparatus as claimed in any one or more of the preceding claims, wherein each wall is integral with its neighbour.13. Trench access apparatus as claimed in any one or more of the preceding claims, and formed as a single piece unit.14. Trench access apparatus as claimed in any one or more of the preceding claims, wherein at least one wall is arranged to receive a wall extension panel to increase the height of the apparatus in the region of the said at least one wall.15. Trench access apparatus as claimed in Claim 13, wherein the wall extension panel comprises a wall extension unit having a pair of opposed first walls and a pair of opposed second walls arranged to extend upwardly from the respective first and second walls of the apparatus 16. Trench access apparatus as claimed in any one or more of the preceding claims, and of modular form comprising the said opposed first and second walls, and at least a first wall extension unit.17. Trench access apparatus as claimed in any one or more of the preceding claims, wherein the bottom of at least one pair of opposed walls is provided with at least one travel formation arranged to assist with movement of the apparatus along the surface of the trench bottom.18. Trench access apparatus as claimed in Claim 17, wherein the said travel formation comprises a skid/ski.19. Trench access apparatus as claimed in any one or more of the preceding claims, and arranged for movement in the longitudinal direction of the trench.20. Trench access apparatus as claimed in any one or more of the preceding claims, and including foot-hold formations.21. Trench access apparatus as claimed in any one or more of the preceding claims, and including hand-hold formations.22. Trench access apparatus as claimed in Claim 20 or 21, wherein the hold formations comprise irons.23. Trench access apparatus as claimed in any one or more of the preceding claims, and including engagement formations for manipulation of the apparatus 24. Trench access apparatus as claimed in any one or more of the preceding claims, and arranged for lowering into, and removal from, a trench.25. Trench access apparatus as claimed in any one or more of the preceding claims, and formed from GRP.26. A method of securing a trench for access to equipment exposed within the trench, and comprising lowering apparatus as claimed in any one of more of the preceding claims into the trench to straddle the equipment and provide a trench access space for access to the equipment.