DE1958882A1 - Prestressing or supporting rope and devices for its anchoring - Google Patents

Description

Pierre Andre H abib, Paris (France) Coyne et Bellier, Bureau d ¹ Engineers Conseils,

Paris, France.)

Prestressing or supporting rope and devices for its anchoring

The invention relates to a pre-tensioning or support cable, which is used in particular for pre-tensioning buildings serves.

In civil engineering ropes are used, which are generally made up of wires made of high quality steel with assemble a small, circular or approximately circular cross-section. These wires are twisted together in groups and several of these Groups - laid next to each other or twisted together - form the rope.

With such ropes, however, only a mediocre filling of the Kaj that accommodates them is obtained

nals. Furthermore, with changes of direction and with j

009825/136?

-2-

*. INSPECTED

the end anchorages of these ropes in the tensioned state between the wires or between the wires and the channel receiving the rope or the anchoring devices at individual points or Lines of high pressures that have a destructive shear effect. In addition, the manufacture of ropes great performance from a large number of turns, as well as the design, manufacture and the Extremely difficult to use their end anchors.

The aim of the invention is to create a rope that does not have these disadvantages.

To this end, the rope according to the invention is thereby characterized in that it consists of several metal strips of the same thickness, placed side by side, in the there is essentially the same length and generally the same width, which at least one end between at least two clamping members acting perpendicularly on their surface are clamped.

Another preferred feature of the invention is that the rope is clamped between two jaws via ^{spacers which are inserted into the spaces between the 13} brackets and cannot shift in the direction of the tension imparted to the rope.

Because here the pressures in the one from tapes and spacers existing stacks are completely transferred from one jaw to the other, each band is individually with the entire clamping force between two jaw elements (outer jaws or spacers)

00982S / 1367

clamps and can override the tension imparted to the tape these jaw elements are accommodated, provided the clamping force is multiplied by the friction of each side of the hinge is sufficiently high on the jaw elements clamping this band.

However, this clamping force must act on a fairly large area of the belt in order to reduce the pressure per unit area remains low, so that the tension generated in the ribbon cross-section by this pressure is negligible Reduction of the resistance of the belt. Against the tensile force prevailing in it with it brings. ■

The intermediate pieces used between the individual bands of a rope can be thin plates, which extend transversely to the bands or protrude at their ends.

The straps of a second rope or straps of the same rope can also serve as intermediate pieces. In the second For example, the rope is divided into two longitudinal halves and the ends of these halves are ge bent and interlocked.

The ropes according to the invention can, for example, at Suspension bridges or other such structures are used.

In the field of prestressed concrete or metal structures, this type of fastening of the straps to their Ends are used to pretension and anchor the rope at its ends.

-4-

009825/1387 CRicirw inspected

For this purpose, the clamping organs can be used to form age heads, by means of which the Rope can be put under tension and then this tension via intermediate pieces that are between the anchor head and the structure to be prestressed are inserted onto this structure in the form of compression force can be transmitted.

As is also known with ropes made of wires, these jaws can be used to pretension of the rope serving head are formed and then the rope can also be used one or more other jaws in direct contact and with direct support on the structure be anchored.

The ropes according to the invention use the rectangular All available space. By using a friction-reducing material, for example Sheets made of polytetrafluoroethylene, in the convex sections between a rope and this receiving channel can be the rope without local shearing action of the channel or the plates with a low coefficient of friction slide in these channels.

Furthermore, in the production of an inventive Seils the juxtaposition and especially the superimposition of the bands in appropriate Guides are a much simpler and easier job than putting them together Wires for the production of an equivalent rope of known design.

0 0 9 8 2 5/1367 original u ^

Furthermore, treated steel strips can be of high strength with cross-sections are used, due to which each tape with several wires of known pre-tensioning cables is equivalent. This enables a further simplification of the rope manufacture.

When using νθϋ as a pre-tensioning rope, this can rope according to the invention remain freely movable in its guide channel, so that it can be used at a later point in time can be retightened and replaced if necessary.

Furthermore, thin spacers can be used between the bands at certain intervals, which the bands each other in the one intended for the penetration of the final connection of the rope with the structure Keep the required distance from thin-bodied cement.

According to another feature of the invention is to reduce the forces required to anchor the ends of a tensioned rope determine the direction of the tensioned rope Part of the rope in the immediate vicinity of the anchorage changed at least once by removing the rope wrapped around a rounded holder.

The rope can expediently have several successive, opposite changes of direction, since the reduction in tension brought about in this way is independent of the direction of these successive ones Bends depend on the arithmetic sum of the winding angle, by changing this Changes in direction can be avoided too great differences in the length of the individual straps of a rope.

009825/1387

In contrast to the changes in direction that the rope runs learns due to the formation of the structure, are in this case between the holder and the rope and no friction-reducing organs are used between the adjacent bands of the rope.

Further features of the invention emerge from the following description of several exemplary embodiments, reference being made to the accompanying drawing. On this drawing show:

1 shows an axial section through a clamping device provided at one end of the rope along the line I-I of Fig. 2.

Fig. 2 is a section along the line H-II of Fig .. ^Λ .

Fig. 3 is a schematic representation of an example clamping device serving as anchor head.

Figs. 4- and 5 are graphs of those lost by friction Force as a function of the length measured on the rope.

6 shows an axial section through a clamping device consisting of several clamping members along the line VI-VI of Fig. 7.

7 shows a section along the line VII-VII from FIG.

8 shows a perspective illustration of a device which is modified in relation to the device shown in FIGS. 6 and 7 Embodiment.

00382871367

Figure 9 is a side view of another embodiment of the anchor head.

Fig. 1o shows a section along the line X-X of Fig. 9.

11 shows a section through an anchor head which is modified in relation to the anchor head shown in FIGS. 9 and 10 Embodiment.

12 shows an axial section through an embodiment of an assembled anchor head.

FIG. 13 shows a section along the line XIII-XIII from FIG. 12.

For the sake of clarity, the strengths of the bands shown are greatly exaggerated and on all figures in some cases there were gaps between the ligaments and the organs that clamped them released. In fact, however, these elements are in contact with one another and have an essential one lower strength. Furthermore, these elements are actually present in far greater numbers, than shown on the figures.

The rope shown in Figs. 1 and 2 consists of a certain number of overlapping bands 1, which are individually clamped by the clamping device shown in these figures.

For this purpose, intermediate pieces 2 in the form of strips or elongated plates in the between two

-8th-

009825/1367 originally inspected

-8th-

aufeinanaerfolbaren tapes 1 existing gap used and this stack is on the in pressed together in the transverse direction as described below. The intermediate pieces 2 can anchoring elements represent, which at their right end (not shown) fixed to any rigid component connected, or they can be formed by the bands of another rope, the ones shown in Figs. 1 and 2 shown clamping device is used for the butt connection of two ropes.

The clamping device consists of a frame 3, between the large sides of which two jaws 4 can be displaced. These jaws are pressed against one another with the aid of wedges 5 and 6, which are beveled in opposite directions, so that they clamp the straps 1 in place. The wedges have the shape of a right triangle and their hypotenuses lie against one another. The clamping effect is obtained by pushing the wedges against each other.

If the bands and the intermediate pieces have 2 mutually parallel and planar side surfaces, it is not necessarily required between the jaws oil devices for distribution of the pressure on the clamped stack provided.

In the embodiment shown in FIG Inserted between the bands 1 of a rope intermediate pieces 7, which consist of flat elements arranged transversely to the bands. In each between two

0098 * 25/1367

ORlGiNAL!? 'CPECTED

η successive intermediate pieces' existing space and on the outer surfaces of the outermost intermediate pieces are provided filler plates 8, the thickness of which is the same as that of the strips 1. Bending of the intermediate pieces 7 is avoided by means of these filler plates when they rest with their edge on support surfaces for anchoring the rope.

The stack consisting of intermediate pieces 7 and filling plates 8 is enclosed by a housing 9, the bands 1 pass through the bottom 1o and the ends of the non-recessed part thereof Intermediate pieces 7 are in contact. As in the previous case (see also FIG. 7), the stack is between two opposite sides of the housing 9, for example by means of oppositely arranged Wedges 5 »6 or other clamping devices (screws, Winches or working cylinders, spacers and the like.) Clamped.

Here, the wedges act via distributor plates 11 and flat elastic members 12 on the stack to be clamped. These elastic organs can be plates made of rubber or the like. Or, as in the case shown, be finely corrugated metal foils. Thus, the emergence of strong local clamping pressures and thus a · insufficient clamping is avoided.

N is the perpendicular force acting on a belt force and f the friction coefficient, the traction force T, the ten sliding between the band dae einküenmenden elemene is effected, T "2 · · ί Ν. Ee iet ala> practically in all

ORlGiNAL! NS

009826/1117

-Ίο-cases possible to generate a clamping force N that Withstands tensile forces that can lead to the tearing of the tape, even if the value of f is very high is low, for example 0.1.

If the frame -9 is blocked by a wedge, the tensile force acting in the rope is transferred from one side of the frame-to the other over the length L _Q (FIG. 4-) of the clamped rope section from the maximum value T ₀ to 0. There is thus a sliding of the tape between the clamping members as a result of an expansion of the tape which is strongest on the side of maximum tension and 0 on the opposite side. FIG. 4 shows this change in tension over the length L _Q , which also corresponds to the movement of the band section emerging from the clamping elements in relation to them.

However, the vertical force acting on the belt as a result of the clamping must not weaken it in the section of the belt in which there is the maximum tensile stress must withstand · For this purpose, the clamping pressure can be increased by selecting the point of application of the clamping force on the side on which the voltage is O. Furthermore, the clamping surface can be increased by the clamping elements be extended in the direction of the tape length. In the end the clamping elements can be divided into several successive elements * what in particular? has the advantage that the sliding of the 3n:; ui> 3 in every IQosrsorgan is reduced "

009825/1367

If three clamping elements of length L ₁ , L ₂ and L are used (FIG. 5), the tension change in each band can be divided into three parts T ₁ , (T ₂ -T ₁ ) and (T ^ -T ₂ ) to be divided.

Such an embodiment is shown in FIG. The housing 13a is put on the filling plates 8 first with the intermediate pieces and 7 and by inserting wedges 5 _t 6 clamped. Then the housing 13b is attached to the housing 13a and equipped with spacers and filler plates and these are clamped with wedges, etc. In this way, an anchor head is created, with the help of which the rope can be put under tension and then this tension on a Structure can be transferred, on which the anchor head rests with its side 14 via wedges.

Furthermore, the rope can also be pulled by a tensile force exerted on any desired path from the left (on FIG. 6) tension, then on the tensioned rope, the housing 13a 'to 13d place one behind the other so that they are with the the structure to be prestressed are in contact, and then anchor the rope and its tension directly transferred to this structure without wedging.

Instead of the housing 13a to 13d, the on Fig. 8 shown device can be used. This device consists of two opposite one another thick jaws 15 »which are

-12-

009825/1367

ORIGINAL INSPECTED

other oppositely arranged ribs serving to support intermediate pieces 7 and filler plates 8 16 are provided. In the narrow edge of the jaws 15 threaded holes 17 are provided for attachment of end plates 18 with the help of threaded bolts 19 are used. As with the one described above Embodiment can between the pressure-exerting face plates 18 and those of These clamped organs elastic plates 11 are used. The end plates 18 preferably have right-angled bends 18a which grip around the jaws 15 and thus move apart prevent these cheeks.

Since the bolts 19 used to fasten the end plates 18 are only used to maintain the clamping force can be, the clamping force is appropriately supported by any, on an external structure Facilities, such as working cylinders or winches and the like. Generated. You can also use for matching the pressures under the heads of the bolts 19 are elastic organs, for example Belleville springs, be provided. Instead of the end plates 18, U-shaped rods can be provided in each of their ends a single bolt 19 is used.

Both on FIGS. 9 and 1o shown modified This is the embodiment of an anchor head Rope-forming bundles consisting of parallel bands in two equal-sized band groups 1A and 1B shared. The bands of these two groups are opposed around a substantially half-cylindrical Head 22 wrapped and so interlocked,

00982571367

ORIGINA

1958883

that each band of a group is clamped between two bands of the other GrugB. The straps 1A and 1B can also be identical to one another, the rope | forms a loop at its other end. ^{

Preferably, the radius of curvature of the surface of the head 22 decreases on either side of the location at which the ligaments come into contact with him, up to the sight · j tel of the head from (see. Fig. 9). This winding already absorbs part of the tension in the ligaments, so that the clamping members used to anchor the ends of the tape have to use less force.

These clamping members consist of rods 23 which traverse the head 22 in the axial direction and to which Ends further rods 24 are attached. At the ends !

the rods 24 are threaded rods 25. The distribution plates 26 are tightened by cutters 27 and compress if necessary over any '.

saddles 26a provided with elastic elements that of I.

Ribbons 1A and 1B existing bundles in the transverse direction. :

In the embodiment shown in FIGS. 9 and 10, the rope halves run at a certain mutual distance. As FIG. 11 shows, these two rope halves can be reunited. This is what they will do! compressed by a socket 28, which has a be [expanding opening 29, are rounded by the two mutually opposite sides, that the ί belts 1A and 1B of two cable halves are gradually curves overall j. As in the previous case, this development of the straps on the sides of the opening 29 reduces the rope tension and the effect of the adhesive organs 26, 27 is facilitated. 'f

009825/1367

1958382

Another device with which the rope tension is reduced by winding the straps is shown in Figs.

The rope consisting of bands 1 traverses a passage 32 provided in a block 3o Block 3o consists of elements that are connected to one another by bolts 31; the opposite Walls of the passage are oppositely curved so that in it a series of widenings and tapering occurs. Cylindrical bolts 35 »33 are arranged in the center of the widenings. Here, the bolt 35 crosses the side cheeks 3 ^ of the block 3o, while the bolt 33 is loose in the passage.

Each band of the rope is thus first at an angle "around the wall section 36 of the passage 32, then at an angle β around the bolt 33" then at an angle ^ around the curved wall section 37 of the passage, at the angle δ around the bolt 35 and then wrapped around the curved wall portion 38 at an angle i.

With regard to the decrease in tension of the ligaments add up the individual winding angles, so that this undulating course of a winding around a cylinder at an angle corresponds to ot + ft + i + 2 + ε. Furthermore, the loosely inserted The bolt 33 is pulled towards the central taper of the passage 32 by the tensile force exerted on the rope, which causes an additional clamping due to the wedge effect.

009825/1367

Ο ^ ΐΛ

The one consisting of the block in the rope at the exit Tensile stress is greatly reduced in this way. To fully absorb the tensile force, the two cable halves passed by a central wedge 39 on the left and right. This wedge is involved two symmetrical blocks- 4-0 together, the sloping one Have sides and by a spiral tape winding 41 and a hoop 42 placed around them be held together.

The tape winding 41 and the hoop 42 clamp the Rope halves between the wedge 39 and the two blocks 4d elastically together. That way you can the rope, before it is under any tension, can be elastically clamped, whereby during tensioning of the rope, on the one hand, a displacement of the rope and the wedge 39 in the space between the blocks and on the other hand, mutual sliding of the adjacent bands is prevented.

With the anchor head shown in FIGS high tensile forces can be exerted on a rope made of tapes with complete safety.

In the various embodiments described above, ropes are used which consist of Ribbons of the same width exist, i.e. have a rectangular cross-section. In some cases you can the bands, for example, to adapt to a ■ bore with a circular cross-section Widths, but have the same thickness, so that one

009825/1367 c ~ g "'al inspected

receives a tape stack adapted to this cross-section. The clamping elements must here as in the preceding Case must be designed in such a way that they exert even pressure on the construction rope

The invention is not restricted to the exemplary embodiments described above, but rather allows numerous changes. In particular, can
various technical means are replaced by other equivalent means.

009825/1367

Claims (21)

Claims Μ?) Pre-tensioning or! Prague rope, in particular for pre-tensioning buildings, characterized in that it consists of several juxtaposed metallic strips (1) of the same thickness, essentially the same length and generally the same width, which on at least one End between at least two clamping members (3 »5» 6, 9 _t 22-27, 15.3o, 39-42) acting perpendicularly on their surface are clamped. 2. PreloadSf or Support rope according to claim 1, characterized in that it is clamped between two jaws (M-) via intermediate pieces (2) which are inserted into the spaces between the straps (1) and do not shift in the direction of the tension imparted to the rope can· 3. pretensioning or! Supporting rope according to claim 2, characterized in that the intermediate pieces (2) are made of thin, parallel to the longitudinal direction of the strips arranged plates. 4. pretensioning or! Prague rope according to claim 2, characterized in that the intermediate pieces (2) consist of the bands (1) of a second rope. 5. bias or supporting cable according to claim 2, characterized in that the intermediate pieces (7) consist of strips (1A, 1B) consist of the same rope, and that the ^ö eil in the longitudinal direction into two beams overall . ORIGINAL INSPECTED 009825/1367 is divided, the bands of which are bent towards one another and interlocked with one another. 6. biasing or «supporting rope according to claim 2, characterized in that the intermediate pieces (2) thin plates (7) arranged transversely to the belts (1), the length of which is greater than the width of the Bands is, and that between the ends of the intermediate pieces protruding from the bands, filler plates (8) are used, the thickness of which is the same as that of the belts 7. biasing or supporting rope according to claim 1, characterized in that it is clamped before its components is rolled around at least one rounded holder (22, 3o). 8. biasing or support rope according to claim 7 »characterized in that the rounded holder (22) from one of the straps (1) of the rope clamping Baking is formed. 9. pretensioning or support rope according to claim 7, characterized in that the rope before the attachment its ends by rolling on holders (3o, 33 »35) several successive, opposite ones Changes direction experiences. 10. biasing or supporting rope according to claim 2, characterized in that the through the jaws caused clamping by inserting elastic plates (12) is evenly distributed. 009825/1367 j ·· press ■ -19- 11. Pre-tensioning or Support rope according to claim 2, characterized in that the clamping effect of Bake using oppositely inclined Wedges (5, 6) is reached. 12. biasing or supporting rope according to one of claims 1, 2 or 6, characterized in that it is provided with an anchor head, which consists of at least one housing (9), in one of which a recess for the implementation of the rope having bottom (1o) the ends straight, in the transverse direction between the Bands (1) of the rope of opposing intermediate pieces (7) and the edges of between these intermediate pieces inserted, the same thickness as the tapes having filler plates (8), wherein the stacks consisting of tapes, spacers and filler plates perpendicular to their surfaces between two oppositely arranged side walls of the housing is clamped. 13. biasing or supporting rope according to claim 12, characterized in that the anchor head consists of several Housings (13a, 13b, 13c, 13d) of the same area, the side walls of which are against one another issue. 14. Prestressing or supporting rope according to claim 13, characterized in that the anchor head has several housings which are formed by two flat, opposing ribs (16) provided with cheeks (15), the edges of which are attached by end plates (18) are connected to each other, which put together the stack consisting of strips and spacers resting on the ribs. -2o- 009825/1367 -2ο- 15. Prestressing or supporting rope according to claim characterized in that the end plates (18) in the side edges of the ribs (16) The cheeks (15) are fastened by means of bolts (19) which are inserted into threaded holes provided in these side edges are screwed in and elastic washers are used under their heads. 16. Prestressing or supporting rope according to one of the claims 1, 5 or 7 »characterized in that it has an anchor head consisting of an essentially the shape of a cylinder half symmetrical with respect to its center plane having a block (22) consists, around which the interlaced bands (1A, 1B) of the two halves of the same rope are rolled in the opposite direction, with the tapes passing through at least one on one of the block parallel to its axis traversing rod (23) hinged bracket (24-27) pressed against this block are. 17 · Prestressing or supporting rope according to claim 16, characterized in that the radius of curvature of the Blockes (22) gradually decreasing on each side towards the median plane. 18. biasing or supporting rope according to claim 16, characterized in that the peripheral surface of the block (22) extends over more than one cylinder half, and that the block on a base (28) rests, which has an opening (29) to be widened towards the block, at the two of which diverges The two halves of the rope rolled around the block are in contact with the walls. 009825/1367 19. Prestressing or supporting rope according to one of claims 1, 7 or 9, characterized in that it is provided with a voltage reducing device consisting of a block (3o) which has a passage (34) the side walls of which have cylindrical curvatures in opposite directions have and thereby form a series of widenings and tapers in the passage, and in whose expansions cylindrical elements (35 »33) inserted parallel to the generatrix of the walls are. 20. prestressing or supporting rope according to claim 19, characterized in that at least one (33) of the cylindrical elements (33 »35) loosely in the Passage is used. 21. biasing or supporting rope according to claim 1, characterized in that it is in the case in which it is divided into two essentially equal parts (1A, 1B), one formed by two blocks (4o) Has anchor head, between which there is a widening opening, on the wall of which the straps of the two halves of the rope are in contact, a wedge (39) and the entire anchor head being inserted in the middle between the two halves is wrapped with an elastic band. 009825/1387 Emptied