Wharf constituted by arched walls and plane ties

Abstract

The invention relates to a retaining work (12) in ground (S), the work having a vertical front portion and separating a first portion of ground (S1) from a second portion of ground. The front portion (14) is in the form of juxtaposed arched walls (16), each arched wall (16) presenting a concave side facing the first portion of ground and a convex side facing the second portion of ground, and the retaining work (12) further includes a rear portion (20) comprising a plurality of wall elements (22) having their largest faces extending vertically in the second portion of ground (S2), each wall element (22) being arranged between two adjacent arched walls (16) and extending transversely relative to the front portion (14).

Claims

1. A retaining work in ground, the work having a front portion that extends substantially vertically while separating a first portion of ground from a second portion of ground, wherein: the front portion is in the form of a juxtaposition of arched walls extending in a longitudinal direction that is vertical; wherein each arched wall presents a concave side facing the first portion of ground and a convex side facing the second portion of ground; and wherein the retaining work further includes a rear portion connected to the front portion and comprising a plurality of wall elements having their largest faces extending vertically in the second portion of ground, each wall element being arranged between two adjacent arched walls and extending transversely relative to the front portion, wherein the wall elements present a greatest height that is strictly less than the height of the front portion, and wherein the front portion is made of reinforced concrete while the wall elements comprise sheet piling, the sheet piling comprising a plurality of interlocking steel sheet piling members.

2. The retaining work according to claim 1, wherein the front portion has two vertical end edges, and wherein the rear portion also has two other wall elements extending transversely relative to the front portion and arranged on either side of said plurality of wall elements, extending from the vertical end edges of the front portion.

3. The retaining work according to claim 1, wherein the wall elements are plane.

4. The retaining work according to claim 1, wherein the wall elements are parallel to one another.

5. The retaining work according to claim 1, wherein the height of the front portion is substantially equal to twice the greatest height of the wall elements.

6. The retaining work according to claim 1, wherein at least one of the wall elements, when considered lengthwise, has a first end connected to the front portion and a second end opposite from the first end, and wherein the height of the wall element decreases between the first end and the second end of said wall element.

7. The retaining work according to claim 1, wherein the length of the wall elements is greater than the greatest height of said wall elements.

8. The retaining work according to claim 1, wherein the distance between two adjacent wall elements is less than the length of a wall element.

9. The retaining work according to claim 1, wherein at least two of said arched walls are adjacent and connected to each other and to one of the wall elements by a coupling element that presents a first connection portion connected to the wall element and second and third connection portions that are connected to the two adjacent arched walls.

10. The retaining work according to claim 1, wherein the front and/or rear portions are made of reinforced concrete.

11. The retaining work according to claim 1, wherein the front portion and/or the rear portion is a diaphragm wall.

12. A wharf including: a retaining work in ground, the work having a front portion that extends substantially vertically while separating a first portion of ground from a second portion of ground, wherein: the front portion is in the form of a juxtaposition of arched walls extending in a longitudinal direction that is vertical; wherein each arched wall presents a concave side facing the first portion of ground and a convex side facing the second portion of ground; and wherein the retaining work further includes a rear portion connected to the front portion and comprising a plurality of wall elements having their largest faces extending vertically in the second portion of ground, each wall element being arranged between two adjacent arched walls and extending transversely relative to the front portion; and wherein the first portion of ground is situated under the bottom of a body of water such that the front portion separates the body of water from the second portion of ground; wherein the wharf further includes a first rail that extends transversely relative to the wall elements of the rear portion while being supported by a plurality of said wall elements, and wherein the wharf further includes a second rail parallel to the first rail.

13. The wharf according to claim 12, wherein the second rail is supported by the front portion.

14. The wharf according to claim 12, wherein the wall elements present a greatest height that is strictly less than the height of the front portion.

15. A retaining work in ground, the work having a front portion that extends substantially vertically while separating a first portion of ground from a second portion of ground, wherein: the front portion is in the form of a juxtaposition of arched walls extending in a longitudinal direction that is vertical; wherein each arched wall presents a concave side facing the first portion of ground and a convex side facing the second portion of ground; and wherein the retaining work further includes a rear portion connected to the front portion and comprising a plurality of wall elements having their largest faces extending vertically in the second portion of ground, each wall element being arranged between two adjacent arched walls and extending transversely relative to the front portion, and wherein the wall elements present a greatest height that is strictly less than the height of the arched walls and wherein the front portion is made of reinforced concrete while the wall elements comprise sheet piling, the sheet piling comprising a plurality of interlocking steel sheet piling members.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention can be better understood on reading the following description of embodiments of the invention given as non-limiting examples, and in which:

(2) FIG. 1 is a perspective view of a wharf of the invention constituted by a retaining work in a first embodiment of the invention;

(3) FIG. 2 is a side view in section of the FIG. 1 wharf, showing a container gantry installed on a pair of rails supported by the retaining work;

(4) FIG. 3 is a plan view of the FIG. 1 wharf;

(5) FIG. 4 is a side view in section of a variant of the FIG. 1 wharf comprising a retaining work in a second embodiment of the invention;

(6) FIGS. 5A and 5B are comparative graphs showing the values for movement and for bending moments as a function of depth;

(7) FIG. 6 is a plan view in section of the wharf in the first embodiment of the invention; and

(8) FIG. 7 is a plan view in section of the wharf in the second embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

(9) FIG. 1 shows a wharf 10 of the invention including a first embodiment of a retaining work 12 in ground S. The retaining work 12 has a front portion 14 that extends substantially vertically and that separates a first portion of ground S1 from a second portion of ground S2.

(10) With reference to FIGS. 1 and 2, it can be seen that the first portion of ground S1 is situated under the bottom F of a body of water P, and that the front portion 14 presents a depth that is greater than the depth of the water. It can thus be understood that the front portion 14 of the retaining work 12 also separates the body of water P from the second portion of ground S2.

(11) It can be understood that the front portion 14 of the retaining work constitutes a retaining wall having a function of preventing the second portion of ground collapsing into the water P.

(12) As can be in FIG. 2, the height H1 of the front portion 14 of the retaining work 12 is strictly greater than the height H2 of the body of water P, it being understood that the height H2 of the body of water P is defined as the distance between the bottom F and the surface of the body of water P. More precisely, the front portion 14 of the retaining work 12 extends vertically below the bottom F of the body of water P over a height H3. The front portion 14 of the retaining work 12 thus separates the portion of ground S1 from the second portion of ground S2 over this height H3.

(13) Furthermore, the front portion 14 of the retaining work 12 extends vertically above the surface of the body of water P over a height H4.

(14) In this non-limiting example, the height H1 of the front portion 12 is 43 m, the height H2 of the body of water is about 25 m, the height H4 of the portion of the front portion 14 that is above water is about 6 m. Finally, the height H3 of the portion of the front portion 14 that is below the bottom of the body of water P is about 12 m.

(15) In accordance with the invention, the front portion 14 of the retaining work 12 is in the form of juxtaposed arched walls 16 that extend in a longitudinal direction that is vertical. The arched walls are in alignment being arranged side by side so as to form a continuous wall extending in a mean vertical plane X1 that extends along the longitudinal direction of the front portion. As shown in FIG. 3, each arched wall 16 has a cross-section in a horizontal plane that is generally in the form of an arc of a circle.

(16) Each arched wall 16 has a concave side 18 facing the first portion of ground S1 and also the body of water P. Each arched wall 16 also presents a convex side 21, opposite its concave side 18, and facing the second portion of ground S2.

(17) In this example, each arched wall 16 presents a thickness E1 that is of the order of 1 m. It can also be understood that each arched wall 16 extends vertically from the surface over substantially the entire height H1 of the front portion 14 of the retaining work 12. Still in this example, each arched wall 16, when considered in a horizontal plane, presents a radius of curvature R that is of the order of 15 m.

(18) The retaining work 12 also has a rear portion 20 that is secured to the front portion 14 so as to form a single-piece structure. The rear portion 20 comprises a plurality of wall elements 22 formed in the ground and extending vertically from the surface of the ground down to a predetermined depth. It can thus be understood that the large faces 24 extend vertically in the second portion of ground S2. In the first embodiment shown in FIG. 2, the large faces 24 of the wall elements 22 are substantially plane and rectangular in shape.

(19) With reference to FIG. 2, it can be seen that the top level of the front portion corresponds substantially to the top level of the rear portion. In other words, the wall elements 22, 26 extend vertically from the top level of the front portion. Furthermore, the wall elements 22 are secured to the front portion 14 over their full height.

(20) As can be seen in FIG. 3, each wall element 22 is secured to the front portion by being arranged between two adjacent arched walls 16, while extending transversely relative to the front portion 14. More precisely, in this first embodiment, the wall elements 22 extend in vertical planes X2 that are perpendicular to the mean plane X1 in which the front portion 14 of the retaining work 12 extends.

(21) Furthermore, the wall elements 22 are parallel to one another, with the distance d between two successive wall elements 22 being about 15 m.

(22) In this first embodiment, the front portion 14 has two vertical edges 14a and 14b that are opposite from each other, as shown in FIG. 3. The rear portion 20 also has two other wall elements 26 that are likewise transverse relative to the front portion 14 and that are arranged on either side of the plurality of wall elements 22. These other wall elements 26 extend from the end edges 14a and 14b of the front portion 12 so that all of the wall elements 22, 26 are parallel to one another.

(23) More precisely, in this first embodiment, the wall elements 22, 26 are identical and parallel to one another, so that it is only a wall element 22 as shown in FIG. 2 that is described.

(24) Advantageously, the wall elements 22, 26 present a greatest height H5M, that, in this example, is constant over the entire length of the wall elements. In addition, all of the wall elements 22, 26 present the same greatest height. Nevertheless, the wall elements could present different greatest heights without going beyond the ambit of the present invention.

(25) The greatest height H5M is strictly less than the height H1 of the front portion 14. Furthermore, the depth of the wall elements 22, 26 is strictly less than the depth of the front portion 14.

(26) This configuration has the effect that along the height H5M the retaining work behaves like a circular wall, whereas below the wall elements 22, 26, the retaining work behaves like a plane wall.

(27) Furthermore, in the example of FIG. 2, it can be seen that the level of the bottom F of the body of water P lies between the bottom level 14a of the front portion 14 and the bottom level 20a of the rear portion 20. The bottom level 14a of the front portion 14 corresponds to the bottom ends of the arched walls, while the bottom level of the rear portion corresponds to the bottom faces of the wall elements 22, 26.

(28) In this example, the height H1 of the front portion is substantially equal to twice the greatest height H5M of the wall elements 22, 26. In this example, the wall elements extend along a length L that is oriented horizontally. The length L of the wall elements 22, 26 is greater than the greatest height H5M of said wall elements, as shown in FIG. 2.

(29) Furthermore, the distance d between adjacent wall elements 22, 26 is substantially equal to half the length L of the wall elements 22, 26. Such a configuration serves to improve the retaining properties of the retaining work of the invention.

(30) With reference once more to FIG. 3, it can be seen that at least two adjacent arched walls 16 are connected to each other and to one of the wall elements 22 by a coupling element 30 that presents a first connection portion 30a connected to the wall element 22 and first and second connection portions 30b and 30c connected to two adjacent arched walls. The coupling element 30 serves to facilitate connecting together the arched walls and the connecting elements.

(31) With reference once more to FIG. 2, it can be seen that the wharf 10 further includes a first rail 40 and a second rail 42 parallel to the first rail 40 and on which a container gantry 50 can move parallel to the front portion 14 in order to load a container ship 52.

(32) The first rail 40 extends across the wall elements 22, 26 while being supported by said wall elements 22, 26. The second rail 42 is supported in this example by the front portion 14. Without going beyond the ambit of the present invention, the second rail 42 could also be supported by the wall elements 22, 26. In this example, the first and second rails 40 and 42 are fastened to the retaining work 12.

(33) FIG. 4 shows another wharf 10 of the invention that presents a retaining work 12 in a second embodiment of the invention.

(34) Considered along its length L, each wall element 22 has a first end 22a that is connected to the front portion 14 and a second end 22b that is opposite from the first end 22a.

(35) In this second embodiment, the retaining work 12 differs from the first embodiment by the fact that the wall elements 22 of the rear portion 20 present height that is not uniform.

(36) As shown in FIG. 4, considered along the length of the wall element, the height of said wall element 22 decreases going from the first end 22a towards the second end 22b of the wall element 22. In the example of FIG. 4, the bottom face 22c of the wall element 22 presents a staircase-shape, with the greatest height H5M of the wall element 22 being in the proximity of the front portion 14.

(37) There follows a description of a method of making the above-described wharves.

(38) By way of example, in order to make the wharf 10, it is the front portion 14 of the retaining work 12 that is made initially. For this purpose, a diaphragm wall of depth H1 is formed in the ground S of cross-section in a horizontal plane that presents the form of a succession of arches, as shown in FIG. 3. This diaphragm wall is made of reinforced concrete. For this purpose, it is possible to use a drilling tool such as that described in EP 2 295 648.

(39) Thereafter, or simultaneously, the wall elements 22, 26 are formed either in the form of diaphragm walls, or else by excavating using a soil-mixing technique in which sheet piling is inserted. For this purpose, it is possible to use a drilling and mixing tool, such as that described in FR 2 889 608. The coupling elements 30 are also placed between the wall elements 22 and the arched walls 16.

(40) In the examples of FIGS. 6 and 7, the coupling elements 30, 30 are constructed using the tooling used for making the front portion.

(41) By way of example, this comprises diaphragm wall tooling using shuttering such as that described in Document EP 0 101 350, serving to make connections between the coupling elements and the arched walls.

(42) FIG. 6 shows a first embodiment of coupling elements 30. In this first element, the first connection portion 30a is coupled with the wall element 22 by co-operating shapes. In this first element, the wall element 22 is made as a diaphragm wall with continuous reinforcement, as described in Document EP 0 833 987, for example. It can be seen that the reinforcing cage 31 of the coupling element 30 is connected with the reinforcing cage 23 of the wall element 22. Each of the second and third connection portions 30b and 30c is also provided with a reinforcing cage in the form of a connection arm that is coupled with one of the arched walls 16 by co-operating shapes.

(43) In the second embodiment shown in FIG. 7, the coupling element 30 is similar to that of FIG. 6, except that the second and third connection portions 30b and 30c are in the form of setbacks and not of connection arms. The arched wall 16 that is connected to the second connection portion 30b is constituted by two interconnected unitary elements 16.sub.1 and 16.sub.2.

(44) Furthermore, in this second embodiment, the wall element 22 has sheet piling curtain elements 25 connected to the reinforcing cage 31 of the coupling element 30. This sheet piling curtain (e.g., a plurality of interlocking steel sheet piling members) may be rammed directly into the ground, or it may be put into place in an excavation using the soil-mixing technique, as described above, or indeed it may be a slurry wall, as is well known from elsewhere.

(45) In order to make the wall elements 22 of the second embodiment of FIG. 4, four adjacent trenches are dug of respective heights that decrease going from the first end 22a to the second end 22b. This produces the staircase-shape shown in FIG. 4.

(46) In FIG. 5A, the curve G1 shows the movement in millimeters of the retaining work 12 of FIG. 1 as a function of depth, measured from the surface of the body of water P. The curve G2 shows the movement of a prior art retaining work as described above.

(47) In FIG. 5B, the curve M1 shows the values of the bending moments to which the retaining work 10 of FIG. 1 is subjected as a function of depth. The curve M2 shows the values of the bending moments to which the above-described prior art retaining work is subjected.

(48) Calculation shows that the retaining work of the invention presents movements and bending moments that present absolute values that are significantly smaller than those of the prior art work.