GB2488166A

GB2488166A - Girder grillage frame with pile boxes which are variably spaceable

Info

Publication number: GB2488166A
Application number: GB201102882A
Authority: GB
Inventors: Trevor C Burden; Justine Garbutt; Graham Plumley
Original assignee: Francis and Lewis International Ltd
Current assignee: Francis and Lewis International Ltd
Priority date: 2011-02-18
Filing date: 2011-02-18
Publication date: 2012-08-22
Also published as: GB201102882D0

Abstract

A grillage frame 10 with an array of girders 13, 14, which may be rolled steel, the girders being attached to pile boxes 15 which are for receiving the head of a pile 24, 25, the pile boxes being variably spaceable along the length of the girders. The spacing may be varied by sliding the pile boxes along the girders and then clamping them in place with strip plates or bars 30. The grillage may support a pylon or mast 27.

Description

Grillage Frame This invention relates to grillage frames of the type typically used for supporting pylons or towers, for example alongside railway lines or motorways.

Grillage frames of the above type generally comprise an array of steel beams or girders to which the pylon or other structure is secured by bolting, the girders being secured to the ground by attachment to cast concrete emplacements or to piles, either of the cast-in-place type or of the driven type. However, especially where the piles are of the cast-in-place type, the spacings between the individual piles cannot be altered once they have been cast and, accordingly, either the piles require very accurate casting or the subsequent fixing of the grillage frame to the piles requires on-site adaptation of the fixings of the girders to the spacings of the piles.

An object of the present invention is to provide a more adaptable way of securing grillage frames to the ground-engaging piles.

In one aspect, the invention provides a grillage frame comprising an array of girders, the girders being attached to pile boxes for receiving, in use, the head of a pile, in which the boxes are variably spaceable along the length of the girders.

Preferably, the pile boxes are disposed between one or more adjacent pairs of parallel spaced-apart girders, the width of the pile box determining the spacing between the girders. Where more than one pair of girders are employed, respective pairs of beams may be arranged in parallel or in an intersecting arrangement, preferably orthogonally.

The pylon or other structure to be supported by the grillage frame is attached to the frame by an assemblage of connection means which embrace respective pairs of grillage frame girders at a required location, the assemblage supporting a mounting plate to which the pylon or other structure is secured. The mounting plate may be attached direct to the assemblage or indirectly by means of an intermediate bridging plate.

The pile boxes preferably comprise a base member formed with a hole or other aperture to accept the head of a pile, upstanding side walls being attached to the base to form a box-like structure and the walls carrying an array of vertically-disposed holes for receiving, in use, mounting bolts to the girders of the grillage frame. The grillage frame girders are themselves formed with arrays of holes, corresponding with the holes formed in the walls of the pile boxes in terms of their spacing, at their end regions, to receive the pile boxes, and similar arrays of vertically-disposed holes variably along their lengths so that intersecting pairs of grillage frame girders may be secured together by vertical, preferably L-section, strip members bolted to the beams at a desired location along the length of the girders.

In another aspect, the invention provides a kit of parts for on-site assembly of a grillage frame, the kit comprising one or more pairs of girders and pile boxes as hereinbefore described, together with means for connecting the pile boxes and girders together to form a grillage frame, and means for attachment in use to the grillage frame of a pylon, tower or other structure.

In this specification, references to girders include rolled-steel girders of the appropriate cross section and also, where the context allows, other girders or beams as known to the person skilled in the art.

Embodiment of the invention will now be described by way of example with reference to the accompanying drawings, of which: Figure 1 is a side elevation of one confIguration of a grillage frame according to the invention; Figure 2 is a plan view of the grillage frame of Figure 1; and Figures 3,4 and 5 are each side elevation and plan views of further configurations of grillage frames according to the invention.

Referring firstly to Figures 1 and 2, the grillage frame, shown generally at 10, consists essentially of respective pairs of longitudinal C-section girders 11, 12 and lateral C-section girders 13, 14. The girders of each pair are parallel and are spaced apart at at least one of their end regions by pile boxes 15, 16, 17. With reference to pile box 15 by way of example, each pile box consists of a rectangular base plate 18 fanned with a central aperture 19 and carries vertical side walls 20. The side walls are formed with arrays of vertically-disposed holes which, in use, correspond with and are co-axial with holes 21 formed in the end regions of lateral girders 13, 14. The pile boxes are secured between the girders by bolts (not shown) passing through the aligned holes.

The respective pairs of girders intersect to form an unsymmetrical "X" arrangement with the lower flanges of the lateral girders 13, 14 resting on the upper flanges of the longitudinal girders 11, 12. The respective pairs of girders are secured together by means of "L"-strip members 22 bolied to respective longitudinal and lateral grillage frame girders through holes 23. The grillage frame is secured in the ground by virtue of driven piles 24, 25, 26, the heads of which are retained respectively in pile boxes 15, 16, 17.

An upstanding tower or pylon 27 is fonned with a base plate 28 which is bolted to studding bolts 29 which themselves are secured to the upper and lower flanges of the lateral girders 13, 14 by an assemblage of strip plates 30, distal end plates 31 and an upper or proximal plate 32 through which all four studding bolts pass, the assemblage being held together by bolts 33. The studding bolts are tightened to a specific torque to generate the friction required between the strip plates or bars 30 and the flanges of thegirdersl3,14.

As can be seen, the position of the tower or pylon 27 is moveable along the lateral girders 13, 14 between the pile box 15 and the intersection of the pairs of grillage frame girders and, furthermore, additional arrays of vertical holes may optionally be provided along the grillage frame girders to accommodate the pile boxes at different positions or spacings along the girders.

With reference to Figure 3 to 5, Figure 3 shows a grillage frame including a single pair of spaced-apart grillage frame girders 41, 42 separated by and connected to pile boxes 43, 44. Pylon 45 is attached to an assemblage of strip plates, end plates and studding bolts 46, arranged as described with reference to parts 29 to 33 of Figures 1 and2.

Figures 4 illustrates a ftirther alternative grillage frame including a pair of longitudinal grillage frame girders 51, 52 with end pile boxes 53, 54 and supporting two pairs of lateral spaced-apart girders 55, 56 and 57, 58. Girders 55, 56 are separated by and attached to pile box 59 and girders 57, 58 are separated by and attached to pile box 60.

Each pair of lateral girders carries, either coincident with the respective intersections with longitudinal girders 51, 52, or elsewhere along their length, assemblages of strip plates, end plates and studding bolts to support pylons 61, 62 via an intermediate bridging plate 63. Figure 5 illustrates a variant of the grillage frame illustrated in Figure 3, where the parallel grillage frame girders support two respective assemblies of strip plates, end plates and studding bolts to which are attached respective pylons 64,65.

Claims

Claims 1. A grillage frame comprising an array of girders, the girders being attached to pile boxes for receiving, in use, the head of a respective pile, in which the pile boxes are variably spaceable along the length of the girders.
2. A grillage frame according to claim 1, wherein the pile boxes are disposed between one or more adjacent pairs of parallel spaced-apart girders, the width of the pile box determining the spacing between the girders.
3. A grillage frame according to claim 2, wherein the grillage frame comprises more than one pair of girders and respective pairs of girders are aiTanged in parallel.
4. A grillage frame according to claim 2, wherein the grillage frame comprises more than one pair of girders and respective pairs of girders are arranged in an intersecting arrangement. a)
5. A grillage frame according to any preceding claim, wherein the grillage frame further comprises a plurality of connection means for attaching a pylon or other structure to be supported by the grillage frame to the frame, the connection means arranged to embrace respective pairs of grillage frame girders at a required location.
6. A grillage frame according to claim 5, wherein the connection means comprises a mounting plate to which the pylon or other structure is secured..
7. A grillage frame according to claim 6, wherein the mounting plate is attached either directly to the connection means or indirectly by means of an intermediate bridging plate.
8. A grillage frame according to any preceding claim, wherein each pile box comprises a base member formed with an aperture to accept the head of a pile, upstanding side walls attached to the base to form a box-like stmcture, the walls having a first array of vertically-disposed holes for receiving, in use, mounting bolts to the girders of the grillage frame.
9. A grillage frame according to claim 8, wherein the grillage frame girders include a second array of holes, corresponding with the holes of the first array in the walls of the pile boxes in terms of their spacing, at their end regions to receive the pile boxes, and further arrays of vertically-disposed holes variably along their lengths so that intersecting pairs of grillage frame girders may be secured together by vertical strip members bolted to the beams at a desired location along the length of the girders.
10. A kit of parts for on-site assembly of a grillage frame, the kit comprising one or r more pairs of girders and pile boxes as claimed in any preceding claim, means o for connecting the pile boxes and girders together to form a grillage frame, and means for attachment in use to the grillage frame of a pylon, tower or other structure.