DE202009014039U1 - Composite anchor with glass cartridge for the tensile zone - Google Patents

Abstract

Composite anchor, in particular for anchoring in the compression or tension zone in concrete, comprising an anchor rod (1) and a glass cartridge (15) which can be destroyed by the anchor rod (1) and which is filled with a hardenable resin (16) and quartz grains as filler .
characterized in that
the quartz grains present in the glass cartridge (15) are present in the resin (16), preferably a vinyl ester, in a controlled mass distribution of the quartz grains in the hardenable resin (16), the quartz grains being present in at least two fractions
Coarse quartz grains (19a) of 1200-1800 μm size with 75-50% by mass of the total mass of the quartz grains,
- Fine quartz grains (19b) with 125-250 microns size with 25-50% by mass of the total mass of quartz grains are divided.

Description

The The invention relates to a composite anchor, in particular for An anchorage in the generated by load stresses in the concrete Pressure or tension zone, consisting of an anchor rod and a through The anchor rod destructible glass cartridge, which with a hardenable resin and quartz grains filled is.

For heavy duty fasteners in concrete, such a composite anchor system from the EP 0 867 624 B1 known, wherein a composite anchor consisting of an anchor rod having a plurality of widening towards the end of the anchor rod cone sections and is anchored by means of a mortar mass in a borehole of a mounting base. The cone-shaped extensions of the anchor rods provide a good mixing of the mortar mass and a constant load capacity of the composite anchor, even when cracking in concrete. From the EP 0 967 402 B1 another such composite anchor is known, wherein an anchor rod for a filled with mortar composition bore has a shaft having a connection area and an anchoring area with a plurality of axially successively arranged, cone-like extensions and constrictions.

The mehrkomponentige mortar mass is in the well by means of a special glass cartridge introduced. The components for the mortar mass are housed in the glass cartridge in the manner a chamber having a resin component with fillers, e.g. As quartz sand, and a second chamber a hardener component, mostly in powder or liquid form. The glass cartridge is made in the borehole by turning and turning destroyed an anchor rod. By turning the anchor rod The components are resin, broken glass, hardener and more Fillers mixed, so that a resulting Bonding compound evenly between the wall of the Borehole and anchor rod is distributed.

There where the due to component shape and size Load voltages act in concrete, arise so-called pressure or Zones of tension, depending on whether a pressure or tensile load occurs. Especially in the Zugzone can to expand by cracking in the concrete holes, where in conjunction with the concrete, the mortar mass also expands. Here can by an axial displacement of this kind of Anchor rods in the cured composite a Nachspreizen take place, with the cone sections in the narrower area of the mortar shell slipping, so that the anchor rod turn a form-fitting Bonding with the composite material enters and the load on the anchor rod is maintained. For a subsequent spreading, it is necessary that the conical surface of the anchor rod completely detached from the composite mass, but no detachment along the composite surface, d. H. the area between Compound and concrete, occurs.

A separation-ensuring ratio of the composite surface to the cone surface is in the EP 0 867 624 B1 described. This anchor rod has a typical ratio of composite surface to cone surface between 3 and 4.5. The cone sections have a cone angle between 10 ° and 20 °.

An important relationship with respect to the load capacity of the anchor rod is the value of the ratio of the borehole annular gap area, which results from the radial distance of the borehole to the anchor rod, the annular gap, to the bolt cross section of the anchor rod. A value of the ratio of hole ring gap area to the bolt cross section between 0.3 and 0.5 is from EP 0 867 624 B1 known. A high load capacity is achieved by a small annular gap.

The Basic component of suitable mortar compounds consists of a solid hardening resin, usually an epoxy resin or a Acrylic resin. To achieve increased strength, be the resin components mixed with inert fillers, for. As quartz sand, silicates or steel balls of suitable size. The use of quartz sand as a filler allows a cured composite with a large Firmness with a pure two-component mortar can not be reached without fillers. Likewise prevented Quartz sand as filler the typical shrinkage during curing of the resin, which reduced when cracked in the concrete to a Spreading ability of the entire composite anchor and thus one lower load capacity of the anchor rod in the concrete leads. critical Therefore, when curing the composite, how much Filler is present in the glass cartridge. A small share allows a more viscous composite, but can not to the same extent achieve the strength of the surrounding concrete.

A mortar mass that can be pressed into a borehole by hand is out DE 3 226 602 A1 known. The mortar composition has quartz as a preferred filler with a grain size of about 0.1-0.6 mm or 0.1-0.25 mm with a filling of 50-80% in the two-component mass. It is carried out a screening process with the appropriate sieve size and the sieved quartz sand with a statistical distribution of added to different grain sizes of the mortar composition. For borehole sizes from M6 to M16, quartz grains in the lower filling area have proven to be an anchor rod with a maximum annular gap of 1 mm. For boreholes larger than M16, in particular with ring gaps of approx. 1-2 mm, quartz grains in the upper grain range have proven themselves.

A two-component mass for fixing anchor rods with quartz sand as filler describes the US Pat. No. 6,583,259 B1 , wherein the quartz grains have a mean size of 1.2-1.8 mm.

The DE 36 38 750 A1 describes a reaction kit having a multi-chamber cartridge for adhesive attachment of fasteners having a filler content in the resin component of 40-45, examples of which have a percentage of grain sizes on the order of 0.5-1.8 mm or 1.2-1.8 mm, as appropriate Overall composition, specify.

The DE 4 315 788 A1 describes a further composition with one part of binder and 1-6 parts of filler, wherein for a glass cartridge size smaller than M16 quartz grain sizes of 0.8-2 mm and for glass cartridges greater than M16 quartz grains are used with a size of 2-6 mm.

The DE 10 2004 035 567 A1 discloses another two component mortar composition comprising a radically polymerizable resin, fillers, other common mortar components, and a separately disposed hardener component. The resin component contains a mixture of hydroxyalkyl (meth) acrylate and an acetoacetoxyalkyl (meth) acrylate. The fillers consist to a small extent of fumed silica and, as a major constituent of quartz sand, in a certain percentage in an average particle size of 400 μm or smaller than 50 μm. For the former, 20 and 23% respectively, for the latter individual values are given as 26, 29, 37 and 50% based on the total mass.

Furthermore, the describes DE 4131457 A1 a cartridge for chemical fastening technology, which discloses quartz sands with grain sizes of 0.5 to 3 mm, for which cartridge sizes smaller than M16 are selected. For cartridges larger than M20, grain sizes of 3 to 6 mm are specified.

adversely is the sorting of grain sizes in only a single faction. This is only possible to a limited extent a concrete composition of the sizes of the quartz grains and the proportions by weight of the fillers in the To keep the composite mass constant. In the prior art will as well no exact distribution of the quartz grains used based on specific grain sizes for specified hole sizes. With a each variable proportion of quartz grains not exactly known size, also by different Screen results and the simple indication of a mean grain size, becomes a constant filling weight in the composite and thus a consistent strength of any mortar mixture not guaranteed. This deviant strength can be diminished Payloads for set anchor rods with smaller annular gaps especially in the load zones of the concrete, such as the tension or pressure zone, have as a consequence. The resin components used in the prior art show a high strength in the cured state, harden but due to fluctuating temperature and humidity levels very slowly. In particular, methyl (meth) acrylates as a resin component have the disadvantage that they are very irritating in direct skin contact act and continue not directly in air, under the influence of oxygen Harden. By screwing the anchor rod into the drill hole Excess composite mass swells out of the annular gap and forms a drop, the so-called "overflow", which does not harden and thus the installer no way gives the curing of the composite mass to control.

task Therefore, according to the present invention, it is a composite anchor to create an anchor rod with a glass cartridge whose fast hardening compound a controlled mass distribution of quartz as filler also for small annular gaps very high loads in both the compression and tension zones of concrete.

According to the invention said task in a composite anchor of the input mentioned Art solved by a composite anchor with an anchor rod and a glass cartridge destructible by the anchor rod, those with a hardenable resin and quartz grains filled as a filler, with the in the glass cartridge quartz grains in egg ner controlled mass distribution the quartz grains are in the hardenable resin, the quartz grains in two fractions into coarse quartz grains coarse quartz grains with 1200-1800 μm size with 75-50% by mass of the total mass of quartz grains, fine quartz grains with 125-250 μm size with 25-50 mass% of the total mass of the quartz grains, are divided. A preferred percentage distribution of quartz grains sizes is independent of the diameter of the glass cartridge and identical for all cartridge sizes.

preferred Manner is provided here that the fraction of the fine quartz grains turn in turn into two fractions in quartz grains smaller Size with 125-180 μm size with 12.5-25 mass% of the total mass of quartz grains, and medium grain quartz grains of 180-250 μm Size with 12.5-25 mass% of the total mass the quartz grains are divided.

hereby can - against the state of the art - essential lower annular gaps up to 1 mm for pressure zone cartridges and even up to 0.5mm for pull zone cartridges become. This in turn requires better distribution and composition the compound and the constituents, the latter before curing, so that this is improved, evened out and is accelerated. Furthermore, due to the low mass of Compound mass in columns of shrinkage lower, resulting in a higher bond strength results.

The compared to the prior art smaller quartz grains as fillers of the finer grain fraction results an improved strength of the cured mortar composition.

For this contributes further, that just the coarser grain fraction when screwing in the anchor rod rubbing against the borehole wall, the clean them and increase the bond to them as well as shrinking in this case, which in turn to improve the compound force of the mass contributes.

In Another preferred embodiment is a vinyl ester resin used as a resin component in the glass cartridge. This shows by means of a hardener in powder or liquid form in the cured Condition properties of a high-durometer plastic Strength and chemical resistance. By the invention controlled mass distribution of quartz grains in particular in vinyl ester, in addition, a composite strength becomes similar achieved by epoxy resins, but with further advantages in the application. Vinylester shows with a curing time from 20 to 60 minutes a much shorter curing time as comparable epoxy resins, which cure up to 24 h have to. Also is an application in wet wells and at outside temperatures below 0 ° C, wherein the vinyl ester, in contrast to epoxy resin pressure and tensile strength cures. Harden compared to methyl acrylate resins Vinylester resins regardless of the atmosphere even out, bringing the curing process can also be controlled from the outside, which is methyl acrylate not possible, because this on the surface as an "overflow" due to the oxygen level remains liquid, so no statement about that Curing can be done in depth. Although included Vinylesterharze harmful styrene, but are the emission levels for vinyl ester resins during assembly of glass cartridges far below the approval levels. In contrast, Methylacrylates are harmful when in contact with the skin.

The resulting composite has a content of inert fillers of 70-85% by mass and achieved by the defined Distribution of quartz grains in coarse, fine and very fine Grain sizes, both in the tensile zone and in the pressure zone of the concrete very high loads. This one in comparison to the prior art higher content of inert fillers Ensures that a compound with the compressive strength made of high-strength concrete.

Around is to allow a subsequent spreading at anchor rods in the tension zone is the anchor rod in a preferred embodiment with provided with several PTFE or nickel coated cone sections whose Cone angle 8 ° -10 ° or 22 ° -25 °. As has been found to be particularly useful that the anchor rod in the anchored state a ratio of Composite surface to cone surface between 2.5 and 2.9. The preferred embodiment allows also lower ring gaps, with a preferred value of the ratio from borehole annular gap surface to the bolt cross section between 0.12 and 0.25 is.

In a particularly preferred embodiment is provided that the composite anchor according to one of the preceding claims, characterized in that the anchor rod to a for attachment an object certain end of an internal thread for recording having a screw. This can be a particularly stable attachment especially for the train zone, where screws of conventional size between M10 and M20 are usable. Also, screws are more variable Length usable, depending on requirements and geometry of the to be fastened components.

Further Advantages and features of the invention will become apparent from the claims and from the following description in which a preferred embodiment of the invention with reference to the drawings in detail is explained. Showing:

1 a first illustration of an anchor rod according to the invention;

2 a second representation of an anchor rod;

3 a third view of an anchor rod according to the invention after EP 0 697 530 B1 ;

4 a fourth illustration of an anchor rod with an internal thread;

5 a comparison of the resulting annular gap surfaces;

6 a schematic representation of the glass cartridge according to the invention in longitudinal section;

7 a schematic representation of the glass cartridge according to the invention in cross section.

The 1 - 3 show three preferred embodiments of an anchor rod belonging to a composite anchor 1 , At the anchor rod 1 in 1 it is a threaded rod made of suitable steel, with the anchor rod 1 is produced by cutting an endless threaded rod perpendicular to its axis in the desired length and from the end of a tip is made at an angle of 90 °. The attachment background 2 Concrete is drawn schematically and indicates the borehole for the composite anchor. The anchor rod 1 has a marking notch in the upper third 3 up to which the anchor rod 1 pushed into the borehole, with the part of the threaded rod above the mark, an external thread 4 , used to attach an object.

The anchor rod 1 of the 2 has an external thread 4 for fixing an object at the upper end, being attached to the external thread 4 a smooth cylindrical section 5 connects whose length allows an adjustment of the depth in which the on the anchor rod 1 acting forces are introduced into the attachment ground. A tapered shaft 6 leads to three cone sections 7 , The cone sections 7 taper towards the lower end of the anchor rod to the shaft 6 go and go through a steep conical section in each of the adjacent cone section 7 above. The cone sections 7 are by a cone angle 8th embossed, which in the preferred embodiment in 2 22 °. The anchor rod 1 shows three uniform cone sections except for the lowest cone section 7 which has a peak instead of its steep conical section. The series of cone sections arranged in series 7 are on their cone surfaces 9 treated so that after inserting the anchor rod 1 in a composite compound, a lower coefficient of friction is given. For this reason, the cone sections 3 on their cone surfaces 4 each provided with a coating, which consists in the preferred embodiment of polytetrafluoroethylene (PTFE) or nickel.

In another embodiment, not shown here, an anchor rod 1 as they are in 2 you can also see four cone sections 7 have, here the cone angle 8th is also 22 °.

3 shows a further illustration of an anchor rod 1 , this type of anchor rod 1 in itself already from the EP 0 697 530 B1 is known. The anchor rod 1 again has an external thread in the upper quarter 4 for fixing an object. This is followed by a cylindrical shaft 10 in the lower third of the anchor rod 1 in an outer screw thread 11 which ends within a special end nut 12 is screwed. This end mother 12 indicates a conically widening area from its rear end to its free end and a profiling on its outside 13 , This profiling 13 is realized as a V-shaped groove, the helical around the end nut 12 runs around. The composite mass penetrates in this example in the grooves of the end nut 12 and continues to engage behind the conical area of the end nut. Furthermore, the anchor rod 1 a cone angle 8th from 10 ° up. The anchor rod 1 in 3 points in comparison to the anchor rod 1 in 2 also a special coating, which consists of nickel or PTFE.

In 4 is a further embodiment of an anchor rod according to the invention 1 shown, with the anchor rod 1 almost the same features as those in 2 described anchor rod 1 having. At an end intended for attachment of an object is in place of an external thread 4 an internal thread 4a (shown in dashed lines) designed for use with a screw. The internal thread 4a is continuous inside the anchor rod to the end of the cylindrical section 5 designed to accommodate the length of a screw so far that the desired attachment is guaranteed. The diameter of the internal thread 4a is at the diameter of the surrounding anchor rod 1 adapted, preferably internal thread 4a of size M10 to M20 are provided. In principle, the embodiments of an anchor rod can also 1 according to the 1 and 3 such internal thread 4a exhibit.

5 shows an overview of possible ring gaps 14 between the composite anchor and a fixing ground, z. Concrete. In example a) in 5 is an annular gap 14 represented how he z. B. by the anchor rod 1 out 1 is formed, and shows an annular gap width of 1 mm. Example b) in 5 shows an annular gap 14 with a smaller dimension, in the example of anchor rods 1 out 2 or 3 Also ring gap widths between 0.5 to 1 mm are possible. An annular gap for mounting in the pressure zone is approx. 1 mm for corresponding anchor rod sizes of M8-M36. In the tensile zone of the concrete, an annular gap is achieved for sizes of M10-M16 of 0.5 mm and for sizes of M20-M24 of 1 mm. The annular gap area formed by the annular gap is decisive for an important value, which states how the annular gap area to the cross section of the anchor rod 1 , the bolt cross-section is and thus allows statements about the strength of the anchor rod in the borehole. The ratio of the borehole annular gap area to the bolt cross section can here assume values between 0.12 and 0.25. For small values of this ratio, the surrounding composite must have increased strength. A reduced annular gap has a smaller shrinkage of the composite mass in the borehole and thus a stronger bonding force between the borehole wall and anchor rod result.

6 shows a glass cartridge 15 for a curing multicomponent composition based on a free-radically curing resin 16 , in this specific example, a vinyl ester resin. The glass cartridge 15 consists of an outer cartridge 17 and one in the outer cartridge 17 lying inner cartridge 18 , In the inner cartridge 18 there is a hardener in powder or liquid form. In the outer cartridge 17 is the resin 16 Vinyl ester filled with fillers, wherein in the preferred embodiment, the fillers are represented by quartz grains in a specific mass distribution (see 7 ).

The glass cartridge 15 is inserted into a borehole by hammering one of the in 1 to 3 described anchor rods 1 destroyed and those in the glass cartridge 15 components thus activated. By turning the anchor rod 1 during the mixing, a good mixing of the components (resin 16 , Quartz grains, hardeners and glass fragments), which in turn promotes better strength of the hardened mass. The mixture of the components glass-resin-quartz grains and the hardener powder results in a composite mass with a high content of inert fillers of about 70 to 85% by mass, which is achieved by a controlled mass distribution of the quartz grains. The resulting composite material achieves the compressive strength of high-strength concrete 2 ,

7 shows the glass cartridge 15 in the cross section of the axis AA (see also 5 ). The controlled mass distribution of the quartz grains is shown schematically here and illustrates that the distribution of quartz grains in three fractions into coarse quartz grains 19a , fine quartz grains 19b and very fine quartz grains 19c , The coarse quartz grains 19a with a size of 1200 microns 1800 microns in a preferred embodiment in proportionate percent by mass, depending on the cartridge diameter of 75% -50% before, the remaining mass percent of 12.5% -25% are fine quartz grains 19b with 180 μm-250 μm size and very fine quartz grains 19c with 125 μm-180 μm size. The masses refer here to the total physical mass of the quartz grains.

Here are the fine quartz grains 19b and very fine quartz grains 19c in equal parts. It applies in an exemplary embodiment for the specific quartz distribution for any glass cartridge 15 : Grain size [μm] Proportional mass% coarse fine very fine 1200-1800 180-250 125-180 75-50 12.5-25 12.5-25

These grain sizes for the coarse quartz grains 19a , fine quartz grains 19b and very fine quartz grains 19c apply to glass cartridges 15 with the dimension M8-M30 and are in an identical distribution in the glass cartridge 15 in front. The coarse quartz grains 19a take care when mixing the compound by turning the anchor rod 1 in the borehole for further grinding of the borehole wall. Its original size is thereby reduced when screwing in the anchor rod. The fine quartz grains 19b serve, as well as the very fine quartz grains 19c , as a filler between the coarse quartz grains 19a , whereby the composite mass solidifies strongly.

By this controlled mass distribution of the division of quartz grains into three fractions with coarse 19a , fine 19b and very fine quartz grains 19c to divide, this allows the anchor rods of the invention 1 with relatively small annular gaps 14 to set efficiently with a high strength of the cured composite. This also prevents the typical shrinkage when curing the Har zes, which crack in concrete 2 to a reduced ability to spread the entire composite anchor and thus a lower load of the anchor rod 1 in the concrete 2 leads. Due to the quartz grain distribution with different grain sizes and the associated short distance of the quartz grains, a resin layer thickness between the quartz grains resulting from the mixing with the resin component is likewise low, resulting in a significantly stronger composite layer. Due to the controlled mass distribution according to the invention, even at low annular gaps 14 (see also 2 ) very high loads in both the pressure and the tensile zone of the concrete 2 reached.

1

anchor rod

2

Anchoring on concrete

3

notch

4

external thread

4a

inner thread

5

cylindrical section

6

shaft

7

cone section

8th

cone angle

9

conical surface

10

cylindrical shaft

12

end nut

13

profiling

14

annular gap

15

glass cartridge

16

resin

17

outer cartridge

18

inner cartridge

19a

rough quartz grains

19b

fine quartz grains

19c

very fine quartz grains

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 0867624 B1 [0002, 0005, 0006]
• - EP 0967402 B1 [0002]
• - DE 3226602 A1 [0008]
• - US 6583259 B1 [0009]
• - DE 3638750 A1 [0010]
• DE 4315788 A1 [0011]
• - DE 102004035567 A1 [0012]
• - DE 4131457 A1 [0013]
• EP 0697530 B1 [0028, 0036]

Claims (14)

Composite anchor, in particular for anchoring in the compression or tension zone in concrete, with an anchor rod ( 1 ) and one through the anchor rod ( 1 ) destructible glass cartridge ( 15 ), which are filled with a curable resin ( 16 ) and quartz grains is filled as a filler, characterized in that in the glass cartridge ( 15 ) quartz grains in the resin ( 16 ), preferably a vinyl ester, in a controlled mass distribution of the quartz grains in the curable resin ( 16 where the quartz grains are present in at least two fractions as coarse quartz grains ( 19a ) with 1200-1800 μm size with 75-50% by mass of the total mass of the quartz grains, - fine quartz grains ( 19b ) of 125-250 μm in size with 25-50% by mass of the total mass of the quartz grains. Composite anchor according to claim 1, characterized in that the fraction of fine quartz grains ( 19b ) in turn into two fractions: quartz grains of smaller size of 125-180 μm size with 12.5-25 mass% of the total mass of quartz grains, and quartz grains of medium size of 180-250 μm size with 12.5-25 mass % of the total mass of the quartz grains are divided. Composite anchor according to claim 1 or 2, characterized in that the percentage size distribution of the quartz grains for all diameters of the glass cartridges ( 15 ) is identical. Composite anchor according to claim 1, 2 or 3, characterized in that the glass cartridge ( 15 ) consists of an outer and an inner cartridge. Composite anchor according to claim 4, characterized in that the hardenable resin in the outer glass cartridge ( 17 ) is provided. Composite anchor according to claim 4 or 5, characterized in that the inner glass cartridge ( 18 ) is preferably filled with a hardener in powder or liquid form. Composite anchor according to one of the preceding claims, characterized in that the composite mass of a content of inert Has fillers of about 70-85% by mass. Composite anchor according to claim 7, characterized that the cured composite mass a compressive strength of high strength concrete. Composite anchor according to one of claims 1 to 8, characterized in that the anchor rod ( 1 ) with several similarly coated cone sections ( 7 ) whose cone angle ( 8th ) is between 22 ° to 25 ° or 8 ° to 10 °. Composite anchor according to claim 9, characterized in that the coating of the cone sections ( 7 ) consists of PTFE or nickel. Composite anchor according to claim 10, characterized in that the anchor rod ( 1 ) in the anchored state a ratio of composite surface to conical surface ( 9 ) between 2.5 and 2.9. Composite anchor according to one of the preceding claims, characterized in that in the anchored state of the anchor rod ( 1 ) the ratio of borehole annular gap area to the bolt cross section is between 0.12 and 0.25. Composite anchor according to one of the preceding claims, characterized in that the anchor rod ( 1 ) at an end intended for fastening an object an internal thread ( 4a ) for receiving a screw. Composite anchor according to claim 13, characterized in that the internal thread ( 4a ) one size between M10 to M20.