Self-propelled equipment to bore in tunnels

Abstract

 Self-propelled equipment to bore in tunnels, which comprises the following operational units:
- a tracked vehicle (11) bearing a revolvable turret (12) with a control stand (34), the turret being able to revolve by 360°,
- a pair of support structures (14) connected to the opposite ends of the turret (12) and retractably (16) anchored thereto (12),
- telescopic columns (20) actuated by rotation and displacement means (17-18-19) connected to the support structures (14),
- a boring device (15) connected to the telescopic columns (20) and bearing a drilling head (22) for a boring shaft (23) and reinforcements,
- means (33) to monitor the displacement and rotation of the telescopic columns (20), and
- a service crane (36) secured to the turret (12).

Description

[0001] This invention concerns a self-propelled equipment to bore in tunnels. To be more exact, the invention concerns a tracked hydraulic equipment able to carry out lengthwise reinforcements in tunnels.

[0002] The problems linked to the provision of lengthwise reinforcements in tunnels are known in the state of the art.

[0003] It is generally necessary to make a series of lengthwise borings about the roof of the tunnel, and these borings are carried out according to a configuration of truncated cones positioned above the roof.

[0004] When each boring with suitable shaft-wise tools has been completed, the shaft is withdrawn from the boring made in the wall and a cement agglomerate has to be injected into the boring.

[0005] Thereafter a non-recoverable reinforcement having a length substantially the same as that of the boring thus made has to be inserted into the cement agglomerate so as to complete the strengthening.

[0006] This cycle has to be repeated, for each boring made, in succession for each radius of the roof being strengthened.

[0007] The equipment used for the boring, therefore, has to bring to the boring being made, first of all, the boring shaft and then the reinforcement to be inserted.

[0008] The equipment therefore has to be able to move easily within the tunnel, has to be able to anchor itself steadily in the position where the strengthening will be carried out, has to include means to control and ensure proper performance of the boring and also has to provide devices to move and actuate the boring means for the above working operations.

[0009] The present applicant has designed, tested and embodied a boring equipment able to meet all the most demanding requirements of the market and possessing the characteristics needed to carry out any lengthwise reinforcements in tunnels in an economical and very efficient way.

[0010] The invention is set forth in the main claim, while the dependent claims describe various features of the invention.

[0011] The self-propelled equipment according to the invention consists of a tracked vehicle bearing a turret which can revolve by 360°.

[0012] The turret bears at its two opposite ends support structures for a boring device.

[0013] According to a variant the equipment of the invention comprises more than one boring device.

[0014] The support structures enable the boring device to rotate by an arc of a circle and to move radially on a plurality of different working radii.

[0015] During the phases of movement of the self-propelled equipment the support structures can also be lowered so as to be retracted within the overall bulk of the equipment.

[0016] The boring device consists of a support element that bears a drilling head and means to uphold and align a boring shaft and reinforcements.

[0017] The boring device is connected to the respective support structures by means of a joint suitable to permit offsetting of the positions of the support structures in relation to each other according to generating lines of a truncated cone during the boring.

[0018] The equipment of the invention includes a plurality of means to control and monitor the boring conditions, and these means inform the machine operator automatically regarding the correct working of the operations.

[0019] These and other special features of the invention will be made clearer in the description that follows.

[0020] The attached fiogures, which are given as a non-­restrictive example, show the following:-

Fig.1 is a diagrammatic side view of an equipment according to the invention;

Fig.2 is a diagrammatic front view of the equipment of Fig. 1;

Fig.3 shows a variant of the equipment of Fig. 1;

Fig.4 is a diagrammatic front view of the equipment of Fig.1 in some boring configurations.

[0021] In the figures a self-propelled equipment 10 according to the invention consists of a tracked vehicle 11 bearing a revolvable work turret 12.

[0022] The tracked vehicle 11 is provided with actuation means for its movement, these means being advantageously hydraulic speed reducer units complete with a brake for automatic halting.

[0023] The turret 12 is fitted advantageously on a footstep bearing rotatable continuously by 360 degrees and comprises a speed reducer unit for its movement and an automatic brake.

[0024] The turret 12 is also provided with stabilisers 13 for its positioning in height.

[0025] Structures 14 to support a boring device 15 are connected to the two opposite ends of the turret 12. Each support structure 14 can be lowered by suitable overturning means 16 (see Fig. 1) during the phases of movement of the equipment 10 and is thus retracted within the overall bulk of the equipment 10.

[0026] Each support structure 14 comprises a footstep bearing 17 together with relative actuation means, such as speed reducer units 18, a slide block 19 that holds the bearing 17 and a telescopic column 20.

[0027] The boring device 15 is connected to the upper ends of the telescopic columns 20 and in this example is a device to carry out lengthwise strengthening of the tunnel.

[0028] The slide block 19 of each telescopic column 20 can act as an interface, if required, for traditional boring devices carrying out radial borings and for devices suitable for vertical strengthening of the ground.

[0029] In the variant shown in Fig.3 the equipment 10 of the invention comprises a pair of footstep bearings 17-117 and of telescopic columns 20-120 to hold relative boring devices 15.

[0030] This variant provides for the footstep bearings 17-117 and telescopic columns 20-120 to be positioned side by side, thereby enabling borings of an asymmetric type to be made (Fig.3 shows with a line of dashes a boring profile which can be made with the boring device 115).

[0031] According to a further variant the equipment 10 always includes a pair of footstep bearings and telescopic columns with relative boring devices, but these structures are arranged coaxially in series along an axis 43 about which they can oscillate.

[0032] The boring device 15 consists of support means 21 for a drilling head 22 that actuates a boring shaft 23. Non-­recoverable reinforcements to be inserted into the borings made by the shaft 23 cooperate with the drilling head 22.

[0033] The drilling head 22, which may be of a mandrel type but may also have other types of configuration, can slide along support means 21 and cooperates with a transmission box 24 of a drawing chain, for instance, in performing the sliding.

[0034] The transmission box 24 advantageously will also comprise a proximity microswitch for the phase of castig the cement agglomerate, an end-of-run microswitch for the carriage of the drilling head 22 and a drum 25 to take up the cable of a carriage that draws the feed pipes which feed the boring device 15.

[0035] The support means 21 of the boring device 15 are also connected to alignment elements 26 that support and align the boring shaft 23 on the drilling head 22, and also to first clamping means 27 that clamp the boring shaft 23 or the reinforcement, and to second clamping means 28 employed for the unscrewing of the boring shaft 23.

[0036] In its leading part towards the boring area the boring device 15 comprises an anchorage strut 29, which can be moved advantageously by hydraulic actuation and has the purpose of strengthening the position of the equipment 10 when the latter has been aimed.

[0037] The boring device 15 is connected to the telescopic column 20 by means of a universal joint 30 suitable to obtain offsetting of the positions of the telescopic columns 20 in relation to each other and the provision of borings according to the generating lines of a truncated cone.

[0038] Jack means 31 able to compensate torque are connected to the universal joint 30.

[0039] According to the experiments carried out by the present applicant the offsetting thus obtainable of the positions of the telescopic columns in relation to each other reaches a maximum of 7 to 8 degrees and the functioning is fully automatic.

[0040] In fact, the system takes corrective action only when a torsional force greater than the value of the setting of the jack means 31 is applied.

[0041] A support slide block 32 cooperates with the rear telescopic column 20 and compensates errors in the parallelism of the two columns 20 owing to different vertical telescoping or a reciprocal radial offsetting of the positions of the columns 20. In practice, the support slide block 32 makes it possible to vary the distance between the centres of the telescopic columns 20 without leading to anomalous stresses at their attachment point.

[0042] The corrective action is automatic and the system provides a warning light in the event of a breakdown.

[0043] Means 33 to monitor the displacement and rotation of the telescopic columns 20 cooperate with the same.

[0044] The signals are processed and sent to a display located on a control stand 34, thus enabling a machine operator 35 to check continuously the trim of the boring device 15 and to follow the shape of the roof of the tunnel without having to plot the same.

[0045] The equipment 10 can include advantageously a small service crane 36 too which enables the boring zones to be reached easily.

[0046] Fig.4 shows the equipment 10 working within a tunnel 37. In position A the telescopic columns are drawn as being arranged vertically in their position of lowest radial elongation.

[0047] In position B′ the telescopic columns 20 are again shown in their lowest radial position but with a maximum angular displacement in relation to the vertical.

[0048] In position B˝ the telescopic columns 20 are shown in the position of maximum angular displacement of position B′ but in their position of greatest radial elongation.

[0049] Positions C′ and C˝ are analogous to positions B′ and B˝ but have an opposite angular displacement and a value of elongation less than the maximum.

[0050] In the operation of lengthwise strengthening of a tunnel 37 it is possible to identify a zone 38 where the borings are carried out with the boring shaft 23 parallel to the axis of rotation of the telescopic columns 20 and also zones 39, 40, 41 and 42 in which the borings are carried out with the boring shaft 23 tilted at progressively greater angles.

Claims

1 - Self-propelled equipment to bore in tunnels, which is characterized in that it comprises the following operational units:
- a tracked vehicle (11) bearing a revolvable turret (12) with a control stand (34), the turret being able to revolve by 360°,
- a pair of support structures (14) connected to the opposite ends of the turret (12) and retractably (16) anchored thereto (12),
- telescopic columns (20) actuated by rotation and displacement means (17-18-19) connected to the support structures (14),
- a boring device (15) connected to the telescopic columns (20) and bearing a drilling head (22) for a boring shaft (23) and reinforcements,
- means (33) to monitor the displacement and rotation of the telescopic columns (20), and
- a service crane (36) secured to the turret (12).

2 - Self-propelled equipment (10) as claimed in Claim 1, in which the turret (12) is equipped with stabilisers (13) for its positioning in height.

3 - Self-propelled equipment (10) as claimed in Claim 1 or 2, in which the boring device (15) comprises alignment elements (26) and clamping means (27-28).

4 - Self-propelled equipment (10) as claimed in any claim hereinbefore, in which the drilling head (22) cooperates with a transmission box (24).

5 - Self-propelled equipment (10) as claimed in any claim hereinbefore, in which the boring device (15) is connected by means of a joint (30) to the telescopic column (20).

6 - Self-propelled equipment (10) as claimed in any claim hereinbefore, in which jack means (31) are connected to the joint (30).

7 - Self-propelled equipment (10) as claimed in any claim hereinbefore, in which the boring device (15) comprises at its leading end strut means (29) for its anchorage to the borings.

8 - Self-propelled equipment (10) as claimed in any claim hereinbefore, in which a support slide block (32) is connected to the telescopic column (20).

9 - Self-propelled equipment (10) as claimed in any claim hereinbefore, in which the actuation of the support slide block (32) is automatic.

10 - Self-propelled equipment (10) as claimed in any claim hereinbefore, in which the offsetting of the positions of the telescopic columns (20) in relation to each other is obtained automatically.

11 - Self-propelled equipment (10) as claimed in any claim hereinbefore, in which the means (33) to monitor the displacement and rotation of the telescopic columns (20) cooperate with a display located on the control stand (34).

12 - Self-propelled equipment (10) as claimed in any claim hereinbefore, which comprises a pair of bearing means (17-­117) and of telescopic columns (20-120) positioned side by side to hold relative boring devices (15-115).

13 - Self-propelled equipment (10) as claimed in any of Claims 1 to 11 inclusive, which comprises a pair of bearing means (17-117) and of telescopic columns (20-120) arranged coaxially in series to hold the relative boring devices (15-­115).

Drawing