CZ263493A3 - Multiple-part steel rod, particularly a rod of concrete reinforcement, a prestressing rod, an anchor rod or the like - Google Patents

Abstract

A multipart steel bar, in particular a concrete-reinforcing bar, comprises two identical bar pieces (2, 3) which have an approximately oval cross-section and a thread-like, corrugated profiling (10) on the curved side surfaces. The bar pieces (2, 3) are arranged such that they are parallel to one another and make contact with one another in the longitudinal direction in such a manner that a corrugation peak of one bar piece (2) comes to lie in a corrugation valley of the other bar piece (3), said bar pieces (2, 3) forming an overall cross-section with a circular envelope. At least over sub-regions of their length, the bar pieces (2, 3) are fixed by an enclosing device (14) which prevents the bar pieces from separating from one another under loading and may exhibit a corresponding internal thread. The reinforcing bar thus forms a reinforcing element which, although it can be handled as a single-part system, is a multipart element, in the case of which the bar pieces, as a result of the profiling on their inner contact surface, undergo a mutual positively locking connection over their entire length, this permitting, in the installed state, a redundancy of the reinforcing elements which has been unknown in the building industry hitherto. <IMAGE>

Description

Technical field

The invention relates to a multi-part steel bar, in particular a reinforcing bar, a prestressing bar, anchoring bar or the like.

BACKGROUND OF THE INVENTION

Building reinforcement elements such as tempered reinforced concrete fittings, prestressing elements, tensile or compression elements for ground anchors and rock anchors or piles and the like consist of one-piece or multi-piece systems, such as single members or bundles, of several individual elements. Usually these systems are used side-by-side depending on the purpose of use. Reinforcement elements for reinforced concrete usually consist of individual reinforcement elements that are embedded in the concrete of the component. The prestressing elements for prestressed concrete may consist of a single individual element, for example also steel reinforcement, or a bundle of several individual elements, such as steel wires or wire ropes, which are located to provide longitudinal mobility when prestressed relative to hardened concrete in the conduit ducts . The prestressing elements can be additionally connected by grouting the cementitious slurry with the respective component or, in the absence of a prestressing, they can be injected with an anticorrosive material for corrosion protection.

Individual systems, such as steel elements, have the advantage that they are provided with screw threads and can thus be directly anchored by screwing in the anchor rods or extended by slippers. In multi-part systems, such as rope bundles, conventional wedge anchoring may be used, either individual or all elements being prestressed and anchored together.

The safety of reinforced concrete or prestressed concrete works depends entirely on the condition of the reinforcement elements. The concrete surrounding the reinforcement elements, in the prestressing elements, the cement mortar filling the additional prestressing channels to form an additional connection, prevents corrosion. At the same time, these reinforcements are inaccessible and hence uncontrolled, or when connected to a component, they are also not replaceable inside the building, so that the state of operational damage, for example caused by corrosion, is not detectable from the outside. The safety assurance is therefore aided by the use of a safety coefficient when dimensioning the reinforcement insert or determining the allowable stress. Despite this, one-piece systems, especially in building offices, are becoming increasingly skeptical, because in the event of a failure of one part, the entire system is quickly shut down. However, if one element fails in a multi-part system, the preloading element of the beam, the remaining elements can provide additional safety.

SUMMARY OF THE INVENTION

On this basis, the object of the invention is to achieve a high safety against failure of the whole system in a one-piece system, for example a steel rod.

According to the invention, a combination of the features mentioned in claim 1 serves to solve this problem.

Advantageous further developments are apparent from the subclaims.

In these solutions, the invention partially extends back to two known embodiments. Thus, on the one hand, a reinforcing element or a hot-rolled anchoring element is known which consists of two or more mutually parallel bars complemented by a circular envelope over the entire cross-section on which an anchoring means having rounded ribs is positioned over the entire outer surface. DE-AS 18 13 627. Thus, two or more individual elements, which may also have an oval cross-section, are connected to the system, yet each individual element nevertheless acts independently. On the inner contact surface of the individual bars there are inclined ribs, which only have to be achieved if the individual bars additionally extruded with mortar are fully surrounded by the extruded material.

Further known is a reinforcing bar with hot-rolled helical ribs which are located on two opposite sides of the circumference of the rod and form part of the thread, the longitudinal section of the rod in the region of the ribs generally showing a smooth rounded curve. in an otherwise circular cross-section of the core, they form valleys between the ribs, as described in DE 35 17 638 G2. The benefits of these reinforcing bars are *

especially in the production method. The shallow valleys must act as pressure points during rolling, which can easily and evenly fill the corrugated ribs with material. The rounded shape of the ribs must, among other things. prefer to temper the rib during rolling. The cross-sectional area of the bar is practically constant over its entire length, which is also advantageous for the rolling process.

The one-piece system will be usable by the invention, but multi-part reinforcement elements are proposed in which individual bars, including profiling, on their inner contact surface along their entire length enter the closed connection. In this way, a reduction of the reinforcement elements which has not been known in the construction industry for the first time is achieved in the installed state. By uniformly curved profiling, the individual rods are precisely matched to each other in their contact surfaces, so that the transmission of force from one rod to another is ensured when the two rods are fixed against each other.

In the case of concreted reinforcing elements, this fixation is ensured by the concrete surrounding the reinforcing elements. For the prestressing elements, the fixation can normally be achieved by a sleeve which is concreted and grouted with a cement paste. In the anchoring area, the fixation can be achieved by an anchor, generally characterized as a nut, having a female thread suitable for through bar profiling. In order to create the clearance required to screw the nut, it is expedient for the female thread of the nut if the length of the rounding apex is made shorter and the length of the rounding mine longer than the same part for the beam.

Description of the drawings

The invention is further illustrated by the drawings, in which:

Fig. 1 is a cross-sectional view of a steel rod according to the invention consisting of two partial bars; Fig. 2 is a longitudinal section of a steel rod in the nut region; Fig. 3 is a cross-section along line III-III in Fig. S; on the inside of the nut in an enlarged view.

Example 1. „Pro.ved.e.n.í ... vyn.á ls_zu

The steel bar 1 shown in FIGS. 1 to 3 consists of two partial bars 2, 5 which are formed in the same way. The partial rods 3, 3 have, as can be seen from FIG. 1, a substantially oval cross-section with two opposing, curved side surfaces 4 and 6, respectively 6 and 7 and straight or weakly curved front surfaces 8 or g.

In the area of the curved side surfaces 4 and 5, respectively 6 and 7, the partial bars 2 and 3 are provided with rounded profiling LO, which forms the rounding apex 11 and the rounding mine 12, as shown in FIG.

and FIG. 2. The undulating profiling 10 preferably follows a sinusoid in which, as indicated by dashed lines, the curvature apex 11 rises above the original perimeter 15 of the rod core S, 3 and the fillet mine 12 forms a trough below the perimeter 15 of the rod core. The profiling 10 is uniform, the length 1 of the rounding apex 11 and the rounding mine 12 are identical. The profiling 10 follows the helix so that the rib radius 11 and the groove radius 12 form screwable threads.

The two partial bars 2 and 3, as can be seen in particular in FIG. 2, are in close contact with each other with their inwardly facing side faces 5, 6, so that the rounding tips 11 of one partial bar 2 or 3 are aligned of the adjacent member 1 or 2 and vice versa. Thus, the two partial bars 2 and 3 are toothedly connected to one another in the axial direction.

Generally, this positive connection can only be maintained if it is ensured that the partial bars 2 and 3 cannot be separated from the positive connection, for example, under different axial forces. This is achieved by an annular clamping, which in the embodiment shown in Figs. 2 and 3 consists of a nut 14. having an internal thread 15 corresponding to the threaded profiling 10 of the rods 2, 3. The nut 14 is here an exemplary anchoring body supported against the abutment surface. a fastening element positioned at any point along the steel bar I or a fastening element, for example a sleeve.

The profiling of the internal thread 15 of the nut 14 has the same pitch s as the profiling of the 10 members 2 and only for the different diameter of the thread formed by the profiling 10 or the internal thread 15 is the thread travel inclined to the longitudinal axis of the steel 1. nut 14.

The profiling of the female thread 15 on the inside of the nut 14 essentially follows the profiling 10 on the lateral faces 4, 5, possibly 8, 7 of the sub-members 3 and 3. In order to achieve sufficient clearance to screw the nut 14 measured between the turning points smaller and the length I2 of the rounding of the nut 14 greater than the corresponding lengths 1 of the sub-members 3 and 3.

Claims (3)

PATENT CLAIMS Multi-part steel bar, in particular a reinforcing bar, prestressing bar, anchor rod or the like, characterized in that the steel bar (1) consists of two equally formed partial bars (2, 3) with oval cross-section and threaded profiling (10) In the longitudinal section along the axial plane, the profiling (10) of the partial bars (2, 3) has a uniformly rounded course in which the apex (11) has a rounding and a mine (12). ) the rounding of the same length (1), the partial bars (2, 3) are placed parallel to each other and in longitudinal direction they touch each other, the rounding tip (11) of the partial bar (2 or 3) being located in the rounding mine (18) of the second of a partial beam (3 or 2), and form a circular cross-section with a circular sleeve, the radius of curvature of the lateral surfaces (4, 5 or 6, 7) of the partial beams (2, 3) corresponding to the radius p the collars and the rods (2, 3) are clamped at least in part of their length. Steel bar according to claim 1, characterized in that the rounding tips (11) of the partial bars (2, 3) form threaded ribs and the rounding mills (12) form threaded valleys, the clamping consisting of a nut (14) provided with an internal thread ( 15). Steel bar according to claim 2, characterized in that the internal thread (15) of the nut (14) has a shorter length (li) of the rounding (16) of the nut (14) and a length (I2) of the mine (14). 17) a rounding of the nut (14) longer than the corresponding length (1) of the rounding apex (11) and the rounding mine (12) of the partial beam (2,3).