SUBJECT OF THE INVENTION
[0001] The present invention relates, generally, to a method for carrying out construction
work underneath roadways or railways without interrupting the traffic.
[0002] More specifically, the present invention relates to a method for eliminating road
and railway line intersections by providing a bottom passage structure outside of
its final location and arranging it in position by means of displacement or thrusting
of inserted caisson elements, while ensuring continuous communication above the intersection.
STATE OF THE ART
[0003] It is known in the state of the art to eliminate an intersection level crossing by
means of the prefabricated construction of a bottom passage underneath the intersection
and its installation using the thrusting or inserted caisson technique.
[0004] Elimination of the level crossing at an intersection comprises at least the following
operations: manufacture and arrangement of the caisson, provision of a receiving surface,
after construction of the caisson outside of its final location, which is as close
as possible to the final receiving surface for the inserted caisson, in order to reduce
the distance which the caisson must travel and in any case must be equal to the length
of the caisson plus the space needed to house the thrusting wall or reaction wall
for the thrusting forces and the hydraulic thrusting jacks.
[0005] After performing the aforementioned tasks which will be performed by means of the
method which is most suitable in each case and which will be determined by the ground
and space available, the next step involves construction of a reinforced-concrete
sliding sill, with lateral guiding rails at the base of the caisson, the function
of which will be to prevent lateral displacement of the caisson.
[0006] The sill has a dual function: on the one hand to create a sliding surface for the
caisson and, on the other hand, to act as a formwork for the construction of the associated
caisson.
[0007] At the most distant end of the intersection the reaction wall intended to withstand
the thrust of the hydraulic jacks is constructed.
[0008] In each case, the dimensions of both the sill and the reaction wall and the number
of jacks depend on the weight of the caisson to be pushed into position.
[0009] Once the wall and sill have been constructed and after the setting time for the concrete
used, a sheet of polyethylene or similar material of a certain thickness is extended
over the latter, this having the function moreover of separating the sill of the caisson
which is to be constructed from the sliding sill and reducing horizontal friction
during displacement, which is of fundamental importance during the initial stage thereof.
[0010] During the forward thrusting operation it is necessary to move the support point
of the hydraulic jacks, namely construct successive counter thrusting slabs depending
on the displacement of the caisson. The function of the counter thrusting slabs is
to ensure correct transmission of the force.
[0011] The slabs of the highly reinforced constructed caisson have different functions:
the bottom one for supporting a travel way allowing the passage of vehicles, trains,
pedestrians, etc., and the top one for supporting the traffic of vehicles, trains,
pedestrians, etc.
[0012] The caisson has a form with a number of rib-like ties at the front thereof, the purpose
of which is to provide the least possible resistance to the forward movement against
the ground and secure it laterally, for which reason said stirrups are chamfered in
their plane of contact with the ground; at the top thereof it has a number of auxiliary
beams, the function of which is to brace the ribs and act as a support point for the
manoeuvring beams.
[0013] The inclination of the ribs is determined depending on the angle of contact of the
ground and the need to ensure almost simultaneous contact of the ribs and the bottom
slab with the ground.
[0014] The support beam situated at the front end of the ribs and seated inside the grooves
of both ties has the function of providing a support for transverse metal sections
which are arranged underneath the sleepers and in the thrusting direction. Generally
the transverse supports are composed of fastened pairs of I-beams type in the form
of a "II" which are arranged depending on the slant and separated from each other
1.20 m to 2.40 m between the axes. Usually several pairs of fastened sections are
mounted above the caisson.
[0015] The transverse support, i.e. fastened sections, have the function of supporting the
associated track and transmitting the loads of the rolling stock which travel on the
rails and create a surface below which the caisson is slid.
[0016] In order to ensure sliding between caisson and fastened sections, round members are
arranged between the latter and the top of the caisson in order to facilitate said
sliding movement and the fastened sections are braced at the start of the thrusting
movement so that they are not subject to any movement with the continuous displacement
of the caisson.
[0017] Sometimes it is necessary to position wood wedges between the transverse supports
and the cross ties, these having the function of ensuring the correct level or elevation
of the track during insertion of the caisson.
[0018] Moreover, longitudinal shoring is provided above each railway track, consisting in
arranging a pair of sets or series of tracks parallel to each track line, fixed by
a clamp on both sides of the track line and braced by a number of perpendicular sections
or tracks which fix together both sets, supporting at the same time the load of the
tracks at the moment when, for working requirements, the support provided by the ballast
is no longer present.
[0019] Therefore it is required to develop a method for insertion of a caisson which allows
the trains to pass through more rapidly than hitherto while displacement of the caisson
from the construction location to its final location is being performed, forming a
lower passage of a railway line.
[0020] EP 1 621 671 A2 discloses a modular system for provisionally supporting working railway tracks during
under-track works. In order to carry out infrastructures such as underpasses under
the railway tracks a number of rails are arranged in a parallel arrangement with respect
to the railway track, the rails being inferiorly connected to each other by a transversal
rail section, this system being nevertheless hard to implement and lacking in solidity.
The modular system of the invention comprises a plurality of loadbearing crossbeams
being arranged in an inferior and transversal arrangement with respect to the railway
track rails, the loadbearing crossbeams being parallel to the crossties, and a number
of pairs of longitudinal staying beams being arranged in a parallel arrangement with
respect to the railway track rails in the middle area between them and at both their
sides, said staying beams resting on the plurality of loadbearing crossbeams, the
loadbearing crossbeams and the staying beams being joined together by means of lowerable
steel blocks.
[0021] In the same way,
DE 1 205 575 B and
ES 2 151 364 A1 disclose supporting arrangement intended to be arranged in a shoring zone of railway
track where numbers of rails are arranged in a parallel arrangement with respect to
the railway track, the rails being inferiorly connected to each other by a transversal
rail section.
SUMMARY OF THE INVENTION
[0022] The present invention aims to eliminate or palliate one or more of the abovementioned
drawbacks by means of a supporting arrangement as claimed in Claim 1. Embodiments
of the invention are defined in the dependent claims.
[0023] One object of the invention is to provide a shoring system for railway lines in the
insertion zone which avoids the use of transverse supports, or fastened sections,
above the top part of a caisson which is being inserted in position.
[0024] Another object of the invention is to avoid the installation of the longitudinal
shoring assemblies which are at present used, assembly and disassembly of which is
relatively time-consuming.
[0025] Another object of the invention is to provide a self-supporting shoring arrangement
which avoids interruption of the railway traffic during assembly and disassembly thereof.
[0026] Yet another object of the invention is to reduce the duration of the process for
moving the caisson since the railway track is self-supporting and the installation
of transverse supports above the top part of the caisson is not required. As a result,
the completion times for the whole work are reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] A more detailed explanation of the invention is provided in the following description
based on the accompanying drawings in which:
[0028] Figure 1 illustrates the process for insertion of a caisson according to the state
of the art;
[0029] Figure 2 shows a plan view of an arrangement for supporting the railway track according
to the invention;
[0030] Figure 3 shows an elevation view of a longitudinal section of Figure 2 according
to the invention;
[0031] Figure 4 shows an elevation view of a longitudinal section along the axis A-A of
Figure 2 according to the invention;
[0032] Figure 5 shows an elevation view of a longitudinal section along the axis As-As of
Figure 2 according to the invention;
[0033] Figure 6 shows an elevation view of the cross-section along the axis Xr-Xr of Figure
2 according to the invention;
[0034] Figure 7 shows an elevation view of the cross-section along the axis Xr-Xr of Figure
2 according to the invention; and
[0035] Figure 8 shows an elevation view of a mechanical fixing means according to the invention.
DESCRIPTION OF THE INVENTION
[0036] Below, with reference to Figure 1, a process for inserting a caisson is shown, it
being possible to see the transverse support 11, i.e. fastened sections 11 which have
the function of supporting the associated track and transmitting the loads of the
rolling stock travelling on the rails and creating a surface below which the caisson
is slid.
[0037] One of the advantages of the present invention consists in the elimination of the
fastened sections 11 of metal beams, which ensures at all times correct positioning
of the railway track, below which construction of a passage below the railway is performed.
[0038] With reference now to Figure 2, the shoring arrangement according to the invention
comprises first metal shoring beams 12, a first longitudinal metal beam 12 arranged
parallel to a line 17 of the track on the outer side of the track line 17, that is,
between the two track lines 17 there is no longitudinal beam 12 installed.
[0039] The set of first longitudinal beams 12 is braced by a second set of perpendicular
metal beams 14, with a length less than the first longitudinal beams 12, which fix
together both first longitudinal beams 12. Joining of each first longitudinal beam
12 to a second beam 14 is performed via a mechanical fixing means 15 such as a tie,
flange, clamp or the like, see Figure 3.
[0040] The fixing system 15 has the function of joining one end of the second beam 14 to
a first longitudinal beam 12 on the outer side of the railway line 17. Consequently
travel of the trains through the shoring zone is not necessary since, in order to
perform the shoring work before insertion of the caisson, it is not necessary to occupy
the space between railway lines 17.
[0041] With reference now to Figures 2, 3 and 5, the second perpendicular metal beam 14
is installed between two sleepers 16 and generally in the direction of thrusting of
the inserted caisson.
[0042] The spacing between two second perpendicular beams 14 will correspond to a minimum
distance substantially equivalent to the width of a sleeper 16 and a predetermined
maximum distance corresponding to the width of several sleepers 16 and the spacing
between the sleepers will be based on the rolling stock travelling along the tracks.
[0043] Where necessary it is possible to add wedges to the second perpendicular beams 14
in order to maintain the elevation of the track in the shoring zone.
[0044] With reference now to Figures 2, 3, 5, 6 and 8, the fixing system 15 which joins
one end of the second beam 14 to the first longitudinal beam 12 will be described.
[0045] Preferably, the first longitudinal metal beam 12 is a hollow beams, that is, cellular
I-beam comprising cavities 13 which may be circular, hexagonal, octagonal or the like,
or a cellular beam with H or double-T shaped cross-section, which flanges are wide
enough to form in the flanges sets of parallel through-holes and in which the holes
of one flange are aligned with the holes of the other opposite flange, see Figures
3, 4, 6 and 8.
[0046] The profile of the first longitudinal beam 12 comprises flanges and a web comprising
cavities 13 with a cross-section adapted to the cross-section of the second perpendicular
beam 14 which passes through said cavity 13, see Figures 3, 4, 6 and 8.
[0047] In this latter case cavities 13 will be formed, spaced from each other on the basis
of the distance separating, from each other, the second perpendicular beams 14 which
brace the first longitudinal beams 12.
[0048] The cross-section of the cavities 13 to be formed will depend on the cross-section
of the second perpendicular beam 14 which braces the first longitudinal beams see
Figure 8.
[0049] With reference now to Figures 6 and 8, the sets of through-holes are formed in both
flanges on both sides of part of the section which has the cavities 13, so that first
through-bars 15-1, 15-2 pass through the holes situated in parallel flanges so that
a second bar 15-3 perpendicular to the first bars 15-1, 15-2 may be fixed against
one end of the second beam 14 and therefore the second beam 14 is fastened by the
arrangement 15 of first bars 15-1, 15-2 and second bars 15-3 each situated on one
side of the hollow section 12, see Figures 3 and 6.
[0050] The length of the shoring arrangement must be such as to allow the excavation necessary
for displacement of the caisson to be inserted. Consequently, in order to achieve
the aim of supporting the track and transmitting the loads travelling along the rails
it is possible to position adjacent various shoring arrangements as described above,
since in order to obtain the best possible result the length of the first longitudinal
beams 12 corresponds to a predetermined maximum length.
[0051] The embodiments and examples described in this document are intended to provide the
best explanation of the present invention and its practical implementation and allow
in this way persons skilled in the art to put into practice and use the invention.
Nevertheless, persons skilled in the art will recognize that the description and the
above examples have been provided for the purposes of illustration and solely by way
of example. The description as provided is not intended to be exhaustive nor to limit
the invention to the precise embodiment described. Many modifications and variations
are possible on the basis of the above teaching without departing from the underlying
principle and scope of the following claims.
1. Supporting arrangement being arranged in a shoring zone of railway tracks (17), characterized in that supporting arrangement comprises a pair of first longitudinal metal beams (12), each
one of the said first longitudinal beams (12) being arranged parallel to one railway
track (17) on the outer side of each railway track (17), being first longitudinal
metal beams (12) braced by at least a second perpendicular metal beam (14) which ends
are inserted in a sets of parallel through-holes (13) of the first longitudinal beams
(12) and the joining of each first longitudinal beams (12) to an end of the second
perpendicular beam (14) is performed by means of a mechanical fixing means (15).
2. Arrangement according to claim 1, characterized in that the second perpendicular metal beam (14) is located between two sleepers (16) in
the thrusting direction for displacement of an inserted caisson.
3. Arrangement according to claim 1 or 2, characterized in that the profile of the first longitudinal beam (12) comprises flanges and a web comprising
at least a cavity (13) with a cross-section adapted to the cross-section of the second
perpendicular beam (14) which passes through said cavity (13).
4. Arrangement according to claim 3, characterized in that first longitudinal metal beams (12) is a cellular beam with an I-, double-T or H-shaped
cross-section and wide-flange shape.
5. Arrangement according to claim 4, characterized in that the mechanical fixing means (15) comprises sets of holes on both sides of the flanges
of the first longitudinal metal beams (12).
6. Arrangement according to claim 5, characterized in that the mechanical fixing means (15) comprises a first bar (15-1, 15-2) passes through
two holes being situated in facing flanges.
7. Arrangement according to claim 6, characterized in that the mechanical fixing means (15) comprises at least two second bars (15-3) fixed
in position between a pair of sets of first bars (15-1, 15-2), being designed to fasten
one end of the second perpendicular beam (14).
8. Arrangement according to claim 7, characterized in that the mechanical fixing means (15) comprises a tie, flange, clamp or the like.
9. Arrangement according to the preceding claims, characterized in that the shoring zone corresponds to the zone for displacement of a caisson which is inserted.