JPS595725B2 - Reinforcement material for injection anchors - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a steel bar having helically extending ribs, said ribs defining a partial thread, and a fitting or anchor having a corresponding internal thread to said partial thread. This invention relates to a reinforcing member for injection type anchors, which can be screw-fitted.

Known steel bars of this type have the advantage that they can be used both as steel bars for reinforced concrete and as tension steel bars for prestressed concrete, as long as the ribs satisfy the requirements for deformed steel bars for reinforced concrete due to their shape and size.

After all, the ribs form a thread into which an anchor with a corresponding internal thread can be threaded (
(Federal Republic of Germany Patent No. 1784630).

There are also known reinforcing elements for injection anchors that consist of two or more steel rods.

In these reinforcing elements, the individual steel bars complement each other to form a Y-circular cross section.

(Federal Republic of Germany Publication No. 2412459, Japanese Patent Publication No. 56-23493, Patent No. 1081834).

In that case, the individual bars also have ribs that constitute a hot-rolled partial thread, but these ribs only along the outer surface, whereas the individual steel bars touch at the radial joint surfaces. .

Since the transition from this radial joint surface to the outer surface is circular, the grout injection pipe and/or exhaust pipe should be installed in the area limited by these depressions and the circumscribed circle of the cross section. I can do it.

Steel rods made up of such many parts have only limited screw fitability.

This is because individual steel bars have variations in the spacing between ribs due to the rolling process, and as the length of the steel bar increases, these variations accumulate and impair or completely impede thread fitability. Because it will be.

In the case of injectable anchors, in order to create an integral part of the anchor,
A grout injection pipe and an exhaust pipe must be inserted deep into the drilled hole, through which the material forming the anchor integral can be forced in, and the air then displaced can escape through the exhaust pipe.

These tubes are generally composed of small tubes or tubes made of metal or plastic, which are inserted into the borehole together with reinforcing members.

Apart from the additional space required in the case of reinforcing elements with a circular cross section, which prevents the achievement of the smallest possible drilling, these tubes are Risk of damage.

If the reinforcing element consists of two or more pieces, the risk is even greater, since the said parts are connected by means of couplers, and the tubes can then exit outside the coupler. .

The object of the invention is to provide a reinforcing element of the type mentioned at the outset, which can be screwed in completely over its entire length, in order to prevent damage to the inlet and/or exhaust pipes in the narrowest cross-section, while taking up as little space as possible. The purpose is to provide the possibility of being able to prevent this.

This object is achieved in a reinforcing element of the type mentioned at the outset as follows.

That is, the steel bar has in the region between the ends of the ribs at least two circular constrictions starting from the pure cross-section excluding the ribs, and by the circumscribed circle of the pure cross-section excluding the ribs and the ribs. The structure is such that a grout injection pipe and/or an exhaust pipe can be installed in a limited area.

Advantageously, the longitudinal grooves are round and concave.

The advantages of this invention essentially consist in the following points.

That is, by configuring a constriction in the pure cross section of a steel rod having a constriction running in the longitudinal direction excluding the ribs, the grouting pipe and/or the exhaust pipe can be connected to the inside of the circumscribed circle of the pure cross section excluding the ribs. It is possible to provide a

In this way, the tube is well protected from mechanical damage when inserting the steel rod into the borehole by the outer surface of the steel rod defined by the circumscribed circle.

Additionally, this configuration of the steel rod allows the tubes to be inserted through threaded anchors or connectors, effectively avoiding damage to these tubes at such locations. Overall, the hole diameter can be made as small as possible.

Since the ribs forming the partial thread are produced in a single rolling process, the thread has a good thread fit over the entire length of the steel bar.

Therefore, the following advantages exist when rolling this steel bar.

The recess is used to prevent the unavoidable widening of the steel rod from forming a vertical lip that can impair the threaded fit of the steel rod.

(The function of the recess is not impaired by slight deformations that may occur due to widening.

The figures showing examples will be described in detail.

A steel rod 1 whose cross section is shown in FIG. 1 is used as a reinforcing member for an injection anchor.

This steel bar is provided with ribs 2 on two sides facing each other with respect to the plane of symmetry S-8 passing through the center point M, these ribs having already been produced by corresponding groups of rolls during rolling of the steel bar 1. It is something.

Each of the ribs 2 extends over approximately % or more of the circumference of the steel rod.

The pure cross section 3 of the steel rod 1 excluding the ribs has a constricted shape.

The plane of symmetry S-8 between the end faces 4 of the ribs 2 is provided with a rounded constriction 5, which was also created during hot rolling of the steel bar 1. Continuous in the length direction of the steel bar.

A grout injection pipe or exhaust pipe 6, for example in the form of a small plastic tube, is installed in this constriction 5,
These tubes therefore lie inside the circumscribed circle 7 shown in dashed lines of the pure cross section 3 excluding the ribs.

The circumscribed circle 7 corresponds to a complete thread of a fixing device or a connecting device, not shown.

Anchors and couplings can be threaded onto such steel rods without damaging the tube 6'.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view, and FIG. 2 is a partially cut-and-analyzed side view. Symbols in the figure 1... Steel bar, 2... Rib, 3... Pure cross section excluding ribs, 5... Constriction, 6... Grout injection pipe/exhaust pipe, 1... Circumscribed circle .

Claims (1)

[Scope of Claims] 1. Consisting of a steel rod having a helically extending rib, said rib defining a partial thread, into which a fitting or fixing device with a corresponding internal thread is screwed. In a reinforcing member for an injection type anchor that can be combined,
The steel bar 1 has in the region between the ends of the ribs 2 at least y-circular waists 5 starting from pure cross-sections 3 excluding the ribs, and these waists 5 and the circumference of the pure cross-section 3 excluding the ribs. A reinforcing member for an injection type anchor, characterized in that it is configured such that a grout injection pipe and/or an exhaust pipe 6 can be installed in an area limited by a circle 7. 2. The reinforcing member according to claim 1, wherein the constriction 5 is a round depression.