[0001] The object of the present invention is a modular structural element for supporting
excavations inside rock.
[0002] The problem of supporting the excavations inside rock is known, and is solved from
time to time by using structural elements of very different types according to the
requirements of excavation and economic suitability of the materials.
[0003] Such types of structural elements are not generally endowed with characteristics
of homogeneity and modularity, with consequent increases in costs, above all in case
of non-recoverable supports.
[0004] The purpose of the present invention is to obviate the above-said disadvantages,
by providing a modular element which can be applied in any geological situations of
the excavation, and which is easily assemblable and easily realizable.
[0005] Aiming at such a purpose, according to the present invention a modular structural
element has been provided, which comprises a curved structural shape having an "U"-shaped
cross-section, with the flanges of said structural shape being directed towards the
centre of curvature, with, at the ends of said structural shape, in side-by-side
position, curved portions of structural shape with "U"-shaped cross-section with flanges
directed towards the centre of curvature being stably joined, furthermore on the end
sections of said structural shape and of said portions of structural shape, stiffening
plates being provided, and both of them being provided with through slots on their
flanges, and on the stiffening plates. In order to better understand the characteristics
and further advantages thereof, the present invention is now disclosed by referring
to the figures of the hereto attached drawing tables, wherein:
Figure 1 shows a perspective view of a modular structural element according to the
present invention,
Figure 2 shows a plan view of a plurality of elements of Figure 1 assembled with one
another,
Figure 3 shows a partially sectional side view of a plurality of elements of Figure
1 assembled with one another,
Figures 4 and 5 show, for exemplifying purpose, a first diagram of assemblage of structural
elements of Figure 1, respectively in perspective and in plan view,
Figures 6 and 7 show, for exemplifying purpose, a second diagram of assemblage of
structural elements of Figure 1, respectively in perspective and in plan view,
Figures 8 and 9 show, for exemplifying purpose, a third diagram of assemblage of structural
elements of Figure 1, respectively in perspective and in plan view,
Figures 10 and 11 show, for exemplifying purpose, a fourth diagram of assemblage of
structural elements of Figure 1, respectively in perspective and in plan view,
Figures 12 and 13 show, for exemplifying purpose, a fifth diagram of assemblage of
structural elements of Figure 1, respectively in perspective and in plan view,
[0006] Referring to the figures, by the reference numeral 10 a structural element according
to the present invention is generally indicated, which is constituted by a curved
"U"-shaped structural shape 11, extending along an arc of a circumference, with its
flanges being directed towards the centre of curvature, with which curved portion
of an "U"-shaped structural shape 12 are stably joined, e.g., by welding. The portions
12 are located in the nearby of the ends of the structural shape 11 in a side-by-side
position to the same structural shape, and extend by a length equal to one fourth
of the length of the same structural shape.
[0007] Furthermore, both the structural shape 11 and the portions 12 are provided, on their
respective end sections, with stiffening plates 14, whilst slots 15 are provided both
on the flanges and on the stiffening plates 14 of the structural shape 11 and on the
portions 12, in order to make it possible to fasten a plurality of structural elements
to one another.
[0008] Given the particular configuration of the modular structural element 10, one can
easily understand how it can be coupled in the most different configurations according
to the characteristics of the rock concerned by the excavation, i.e., according to
the necessary lining type.
[0009] Given the particular shape of the individual structural element 10, it is possible
to lay it inside the tunnel according to a variety of installation patterns.
[0010] The selection is subordinated to the characteristics of the rock concerned by the
excavation which one wants to line.
[0011] In Figures from 4 to 13, five possible assemblage diagrams are shown.
[0012] The assemblage diagrams of Figures 6-7 and 10-11 make it possible to completely line
the tunnel wall, in that the individual elements 10, by fitting into one another,
completely cover the excavation; they are hence particularly suitable for supporting
the rock in particularly difficult cases, in that a structure closed in this way is
capable of standing a load of approximately 27 kg/cm².
[0013] Due to the rather small dimensions of the individual element, in this case it is
possible to proceed to assemble it, whenever necessary, immediately behind the head
of a cutter machine.
[0014] The assemblage diagrams of Figures 4-5 and 8-9 make it possible to partially line
the tunnel, in that the individual elements 10 are assembled with one another in such
a way as to leave uncovered rock portions, that allows savings to be achieved both
in material supply, and in the assemblage thereof.
[0015] If necessary, these spaces and the voids which are possibly produced between the
metal panels and the rock can be easily eliminated by means of the application of
Spritz-Beton.
[0016] The diagram of Figures 12-13 shows a further application from the very many which
are possible in the assemblage of these elements, in as much as in this case a ring
is assembled, which is composed by 18 elements, and which constitutes a distinct supporting
structure, which is installed at regular distances, which are determined according
to the characteristics of the rock; in this case too, a considerable saving is achieved
in installation times and in material; savings which, however, to not endager the
safety of the whole structure.
[0017] Substantially, with the same element, both partial and total linings can be carried
out, as they are respectively necessary in case of cost savings (favourable geological
situations) and in case of particularly difficult geological situations.
[0018] The present invention has been disclosed for illustrative and not limitative purposes,
but it should be undestood that modifications and changes can be supplied by those
skilled in the art, without going out of the scope of protection of the present invention.
1. Modular structural element comprising a curved structural shape having an "U"-shaped
cross-section, with the flanges of said structural shape being directed towards the
centre of curvature, with, at the ends of said structural shape, in side-by-side position,
curved portions of structural shape with "U"-shaped cross-section with flanges directed
towards the centre of curvature being stably joined, furthermore on the end sections
of said structural shape and of said portions of structural shape, stiffening plates
being provided, and both of them being provided with through slots on their flanges,
and on the stiffening plates.
2. Modular structural element according to claim 1, characterized in that the length
of each one of said curved portions of structural shape in 1/4 of the length of the
said curved structural shape.
3. Modular structural element according to any of the preceding claims, substantially
as herein disclosed and illustrated.