METHOD FOR ATTACHING MOUNTED PARTS TO CONCRETE OR MASONRY

Abstract

A method is defined for attaching mounted parts on a mounting substrate, formed of concrete or masonry, having a group of anchors, wherein the following is true for the ratio VSd/NSd of the rated value for the transverse load VSd and of the rated value of the tensile load NSd of at least one anchor in the anchor group: VSd/NSd≥0.3, preferably VSd/NSd≥0.6 and particularly preferably VSd/NSd≥1.0, and wherein the characteristic resistances of these anchors to transverse loading VRk or to tensile loading NRk satisfy the following relationship: VRk/NRk≤1.1. The at least one anchor of the anchor group is inclined at an angle αAnker to the perpendicular to the surface of the mounting substrate in such a manner that the following is true: αAnker=k*¾*arctan (VSd/NSd) for NSd>0, and αAnker=k*67.5° for NSd=0, where: 0.8≤k≤1.34, providing that αAnker≤75°.

Claims

1. A computer program product, comprising a plurality of instructions, which when executed on a computer system execute the following steps: outputting a Graphical User Interface (GUI) via a display device, wherein the GUI has input fields, which allow a user to input information with regard to a planned attachment of a mounted part to a mounting substrate of concrete or masonry using a group of anchors having anchor heads, wherein this information represents at least a rated value of a transverse load V.sub.Sd and a rated value of a tensile load N.sub.Sd of at least one anchor in the anchor group, or these rated values V.sub.Sd and N.sub.Sd from this information, wherein the GUI is further configured to display whether the planned attachment obeys predetermined rating rules, where at least in the cases in which for a ratio V.sub.Sd/N.sub.Sd of the rated value of the transverse load V.sub.Sd and of the rated value of the tensile load N.sub.Sd of an anchor in the anchor group the following applies: V.sub.Sd/N.sub.Sd≥0.3, and and a ratio of a characteristic resistance to transverse loading V.sub.Rk and to tensile loading N.sub.Rk of this anchor is equal or less than 1.1, wherein each of the values V.sub.Sd, N.sub.Sd, V.sub.Rk and N.sub.Rk refer to an anchor when mounted perpendicular to the surface of the mounting substrate, the computer program is configured to execute a calculation of the rating of this anchor of the anchor group for a mounting with its head tilted in a direction of the corresponding rated value of the transverse load V.sub.Sd by an angle of inclination α.sub.anchor to the normal to the surface of the mounting substrate, wherein:
α.sub.anchor=k*¾*arctan(V.sub.Sd/N.sub.Sd) for N.sub.Sd>0, and
α.sub.anchor=k*67.5° for N.sub.Sd=0, where: 0.6≤k≤1.34, provided that α.sub.anchor≤75°,and to output the result of the rating.

2. The computer program product according to claim 1, wherein the input fields of the GUI allow the user to input information with regard to one or more of the following features: type or nature, respectively, of the mounting substrate; type, size, shape, and material of an anchor plate, rated values with regard to tensile force, transverse force, torsional moment, and/or bending moment, type and/or dimension of the anchor.

3. The computer program product according to claim 1, which is configured to initially calculate a rating for an anchor, which is positioned normal to the mounting substrate, and, in the case that the said anchor does not satisfy the rating regulations rules, alternatively to propose a suitable mounting, which does satisfy the rating rules.

4. The method according to claim 1, where the following applies: 0.6≤k≤1.2.

5. The method according to claim 1, where the following applies: 0.6≤k≤1.15.

6. The method according to claim 1, where the following applies: 0.6≤k≤1.1.

7. The method according to claim 1, where the following applies: 1.34≥k≥0.85.

8. The method according to claim 1, where the following applies: 1.34≥k≥0.9.

9. A computer program product, comprising a plurality of instructions, which, when executed on a computer system, execute the following steps: outputting a Graphical User Interface (GUI) via a display device, wherein the GUI has input fields, which allow a user to input information with regard to a planned attachment of a mounted part to a mounting substrate of concrete or masonry using a group of anchors having anchor heads, wherein this information represents at least a rated value of a transverse load V.sub.Sd and a rated value of a tensile load N.sub.Sd of at least one anchor in the anchor group, or these rated values V.sub.Sd and N.sub.Sd are derivable from this information, wherein each of the values V.sub.Sd, and N.sub.Sd, refer to an anchor when mounted perpendicular to the surface of the mounting substrate, wherein the GUI is furthermore configured to display whether the planned attachment obeys predetermined rating regulations rules, wherein the computer program is configured to execute a calculation of the rating of this anchor of the anchor group for a mounting with its head tilted in a direction of the corresponding rated value V.sub.Sd of the transverse load by an angle α.sub.anchor to the normal to the surface of the mounting substrate, for which the following applies: 35°≤α.sub.anchor≤55°, preferably 40°≤α.sub.anchor≤50°, particularly preferably 43°≤α.sub.anchor 48°, and to output the result of the rating.

10. The computer program product according to claim 9, wherein the input fields of the GUI allow the user to input information with regard to one or a plurality of the following features: type or nature, respectively, of the mounting substrate; type, size, shape, and material of an anchor plate, rated values with regard to tensile force, transverse force, torsional moment, and/or bending moment, type and/or dimension of the anchor.

11. The computer program product according to claim 9, which is configured to initially calculate a rating for an anchor, which is positioned normal to the mounting substrate, and, in the case that the said anchor does not satisfy the rating regulations rules, alternatively to propose a suitable mounting, which does satisfy the rating rules.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0098] FIG. 1 shows a schematic cross-sectional view, which represents an attachment of a mounted part with the aid of two inclined anchors to concrete.

[0099] FIG. 2 shows a sectional view of an attachment of a mounted part in a region close to the edge of the concrete, comprising two normally positioned anchors.

[0100] FIG. 3 shows the same situation as FIG. 2, wherein the anchor, which is closer to the edge, is positioned at an inclined angle with respect to the surface normal according to the invention.

[0101] FIG. 4 shows the same situation as FIG. 2, wherein the anchor closer to the edge is arranged in an elongate hole in the mounted part and the anchor further away from the edge is positioned at an inclined angle to the surface normal.

[0102] FIG. 5 shows an attachment of a mounted part with the aid of two inclined anchors, which receive a tensile load only.

[0103] FIG. 6 shows a screenshot of a GUI of a computer program, which is suitable for carrying out ratings according to the method according to the invention.

[0104] FIGS. 7-11 show different anchors, which can be used in the method according to embodiments of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0105] Further advantages and features of the invention follow from the following description, in which the invention is described on the basis of an exemplary embodiment with reference to the enclosed drawings.

[0106] FIG. 1 shows a cross-sectional view of an attachment of a mounted part 10 to a mounting substrate 12 of concrete with the aid of two anchors 14, which are formed by means of schematically illustrated concrete screws in the embodiment as shown. In the exemplary embodiment of FIG. 1, the mounted part 10 is formed by a metal plate, as could be used, for example, to attach a balcony railing or the like. However, the invention is not limited to certain mounted parts. Rather, any mounted parts 10, in particular those of concrete, can be attached to the mounting substrate 12.

[0107] A transverse load with a rated value V.sub.Sd and a tensile load N.sub.Sd, which are distributed evenly with respect to the corresponding loads V.sub.Sd,1, N.sub.Sd,1 with regard to the upper anchor and V.sub.Sd,2, N.sub.Sd,2 with regard to the lower anchor, acts on the mounted part 10, i.e. the following relations apply: V.sub.Sd,1=V.sub.Sd,2=½ V.sub.Sd, N.sub.Sd,1=N.sub.Sd,2=½ N.sub.Sd. The resultant or total load is inclined at an angle of arctan (V.sub.Sd/N.sub.Sd)=400 to the surface normal.

[0108] In the exemplary embodiment of FIG. 1, the anchors 14 are not positioned normal to the surface of the mounting substrate 12, as is usual in the prior art. Instead they are positioned at an angle α.sub.anchor of 30°, thus ¾ of the angle of the actual resultant load. A significantly higher load can thus be supported than in the case of a normal mounting. The effective installation depth hef is further illustrated in FIG. 1. The effective installation depth hef does not correspond to the length of the anchor 14 in this case, but to the normal projection of the latter, or, in other words, the length of the anchor 14 multiplied by cos(α.sub.anchor).

[0109] FIG. 2 shows a cross-sectional view of an attachment of a mounting part 10 with the aid of two anchors 14 in a region of a mounting substrate 12 of concrete close to the edge. According to the valid rating regulations, the anchor close to the edge has to be designed in this case to support the entire transverse load according to the rated value of the transverse load V.sub.Sd, i.e. applies: V.sub.Sd,2=V.sub.Sd. This is sometimes difficult to achieve in practice, because small edge distances decrease the characteristic resistance to transverse loading V.sub.Rk.

[0110] A solution for these difficulties is shown in FIG. 3, where in the otherwise identical situation, the anchor close to the edge is positioned at an angle of α.sub.anchor=¾*arctan (V.sub.Sd,2/N.sub.Sd), but which has the same placement depth with regard to the surface of the mounting substrate 12, as the normally positioned anchor 14 of FIG. 2. Due to the fact that the anchor that is further away from the edge does not share a proportion of the transverse forces in the rating in this case, there is no reason not to position the said anchor normally in the usual way, as shown in FIG. 3.

[0111] FIG. 4 shows an alternative variant for solving the situation of FIG. 2. In this variant, the anchor 14 close to the edge is accommodated in an elongate hole 16, so that in the rating, this anchor does not share a proportion of the transverse load V.sub.Sd, while the tensile loads are distributed evenly, i.e. N.sub.Sd,2=N.sub.Sd,2=½*N.sub.Sd. The anchor 14 that is further away from the edge, which is positioned at an angle, has an improved load-bearing capacity with regard to this comparatively high transverse load V.sub.Sd,1=V.sub.Sd, as compared to a normally positioned anchor.

[0112] Finally, FIG. 5 shows a variant, in which no pressure-resistant material is present between the mounted part 10 and the mounting substrate 12. A space is shown in FIG. 5, which, in practice, however, can be formed by a non-pressure-resistant material, such as, for example, an insulating material or a plaster, which is not pressure-resistant. In the arrangement of FIG. 5, the rated values of the transverse load V.sub.Sd or tensile load N.sub.Sd, respectively, are distributed evenly to the individual anchors 14, i.e. the following applies: V.sub.Sd,1=V.sub.Sd,2=½*V.sub.Sd, and N.sub.Sd,1=N.sub.Sd,2=½*N.sub.Sd. α.sub.anchor is selected in such a manner in this embodiment that it corresponds to arctan (V.sub.Sd/N.sub.Sd), i.e. the anchors 14 are each arranged parallel to the resulting force and thus only receive a tensile load (with respect to their own longitudinal axis). In the general definition for the angle α.sub.anchor, this corresponds to the case k=1.33.

[0113] A further aspect of the present invention relates to a computer program product, which includes a plurality of instructions, which, when executed on a computer system, output a GUI via a display device, as is shown in an exemplary manner in FIG. 6. Such computer programs are generally of known art and are in common use, and help the user to determine whether a planned application, in this case an attachment of a mounted part 10 to a mounting substrate 12 of concrete, corresponds to the rating regulations. For this purpose, the GUI includes input fields, which allow the user to input information with regard to a plurality of features, for example a field 20 for specifying the mounting substrate (in this case concrete), a field 22 for inputting information with regard to the type, size, shape and material of an anchor plate, fields 24 for inputting rated values of the loads, in particular tensile force, transverse force, torsion moment and bending moment, as well as a field 26 for specifying the type and the dimension of the anchor 14.

[0114] The results of the rating calculation corresponding to the input values and parameters are displayed on the right-hand side of the GUI of FIG. 6. As can be seen in the exemplary screenshot, the planned attachment satisfies the rating regulations with regard to all failure mechanisms, which are considered here, with regard to the tensile loading (steel failure, pull-out, concrete pryout failure). The rating regulations with regard to the transverse loading with regard to steel failure without a lever arm and with regard to concrete pryout failure are further also satisfied, but not the failure with regard to the concrete edge breakage. Here, the transverse loading exceeds the resistance to transverse loading with regard to the failure mechanism “concrete edge breakage” by approximately 20%, the interaction condition is even exceeded by 60%. These results refer to the rating in response to conventional mounting, in which the anchors 14 are positioned normal to the surface of the mounting substrate 12.

[0115] The computer program, however, can also propose ratings in which the anchor is not positioned normally, but at an angle α.sub.anchor to the surface normal of the mounting substrate 12. In the embodiment as shown, the program automatically proposes a rating for an inclined mounting, when certain criteria are met. Such a criterion can be that the rating regulations cannot be satisfied with a normal mounting of the anchor. A further criterion can be that a significantly improved load-bearing capacity can be anticipated in the case of an inclined mounting, for example in cases in which a threshold with regard to the ratio V.sub.Sd/N.sub.Sd is exceeded, or a threshold for V.sub.Rk/N.sub.Rk is not reached. It is advantageous in some cases to consider a design that has a better load-bearing capacity, even if the rating regulations in the case of the planned mounting attachment are also satisfied with a normal mounting. This can prompt the user, for example, to consider a mounting with anchors of a smaller cross section. In some embodiments, the computer program itself can also propose the suitable, generally most cost-efficient anchors, by means of which the mounting attachment can be realized, by utilizing the possibility of an inclined mounting.

[0116] It can be seen in the screenshot shown in FIG. 6 that the rating regulation is not yet satisfied at an angle α.sub.anchor of 34.23°, but that the load-bearing capacity is already significantly better than in the case of normal mounting. At an angle of 38°, in contrast, all rating regulations are satisfied.

[0117] It goes without saying that officially recognized rating regulations do not yet exist for a suitable mounting of anchors in concrete. When reference is thus made in connection with FIG. 6 to “rating regulations”, this relates to the rating regulations, which are expanded to the possibility of an inclined mounting. The analyses by the inventor clearly suggest that significantly improved load-bearing capacities than currently exist can be created thereby in a plurality of applications.

[0118] In a simplified embodiment of the computer program, provision can be made for only one rating to be executed for a predetermined alternative standard mounting angle, for example a mounting angle of 45°. The rating can be executed upon request, i.e. in response to a user input, and/or can be executed automatically. An automatic execution can be considered, for example, when due to the mounting position (closeness to edge, lever arm, etc.) and due to the loads underlying the rating, in particular tensile forces and transverse forces, there are indications that the load-bearing capacity would be increased with a mounting at the alternative standard mounting angle as compared to the normal mounting. It is also possible for the rating calculation for the mounting to be executed as a matter of course at the alternative standard mounting angle and for the result to be displayed, or at least to be displayed if it promises an improved load-bearing capacity.

[0119] The above-described method is not limited to a specific type of anchor. In fact, the term “anchor” is to be understood broadly in the present disclosure, and it can be formed by a one-piece anchor in the strictest sense, as well as by two- or three-piece systems, which will be briefly described below.

[0120] In FIGS. 1 to 5 the anchors 14 each take the form of concrete screws. Such concrete screws are known in the prior art and typically have a self-cutting concrete thread, which forms a load introduction region, a shaft section, and a head, which serves as a power drive for positioning the anchor, as well as for securing the mounted part 10.

[0121] FIG. 7 shows a further example of a one-piece anchor, namely an undercut anchor, which is introduced into the mounting substrate 12 at an inclined angle. On its trailing end, the undercut anchor has a metric thread 28, to which a washer 30 is attached, and which is clamped against the mounted part 10 by means of a nut 32.

[0122] FIG. 8 shows a two-piece anchor, which comprises an anchor sleeve 34, which also provides an undercut. The anchor sleeve 34 is illustrated in FIG. 8 in a partially sectioned manner and has a metric internal thread, into which a threaded rod 36 is screwed. A washer 30 and nut 32 are again arranged on the trailing end of the threaded rod 36.

[0123] FIG. 9 shows a further example for a two-piece anchor, comprising an anchor sleeve 40 comprising a self-cutting external thread 38. Inside the anchor sleeve 40 a metric internal thread is again formed, into which a threaded rod 36 is screwed in a manner similar to FIG. 8. A washer 30 and a nut 32, which are clamped against the mounted part 10, again serve to attach the mounted part 10 to the mounting substrate 12. Here the threaded rod 36 represents an example of an above-cited “clamping element”. The anchor sleeve 40 further has a power drive (not shown in the Figure), by means of which it can be screwed into the concrete of the mounting substrate 12.

[0124] FIG. 10 shows an anchor 14 according to a related embodiment, which is formed by a three-piece system, which comprises a first threaded sleeve 40 of the above-described type, and has a second threaded sleeve 42, which does not include an internal thread. In the illustration of FIG. 10, the mounted part 10 is also a concrete part, which is joined to the mounting substrate 12 with the aid of the anchor 14. Bridge caps or the like are an example for such mounted parts of concrete.

[0125] As shown in FIG. 10, the first threaded sleeve 40 is screwed into the mounting substrate 12, while the second anchor sleeve 42 is screwed into the mounted part 10. A threaded rod 36, which is guided through the (internal thread-free) second anchor sleeve 42, and which is screwed into the internal thread in the first anchor sleeve 40, again serves as clamping element here. When the nut 32 is tightened, the first and the second anchor sleeve 40, 42 are axially clamped in such a manner that the first and the second anchor sleeve 40, 42 generate opposed bond stresses in the mounting substrate 12 or the mounted part 10, respectively.

[0126] FIG. 11 shows a side view and a cross-sectional view of an alternative two-piece system, which is essentially similar to the system of the anchor 14 of FIG. 9. The difference is that the anchor sleeve 40 does not have an internal thread in this case, and that the clamping element is formed by a screw 44 in this case, which is inserted upside down, i.e. head 46 first into the borehole, before the anchor sleeve 40 is screwed in. The head 46 is then located on the leading end of the clamping element 44 and forms a stop element, against which the anchor sleeve 40 can abut so as to transfer a load. This variant is advantageous in that the anchor sleeve 40 can be embodied without an internal thread. Such a clamping element 44, comprising a stop element 46 on the leading end, can also be used for a three-piece system, as shown in FIG. 10, wherein again the clamping element 44 is first introduced into the borehole, and the first and the second sleeve 40, 42 are then guided over the clamping element and are screwed into the mounting substrate 12 or the mounting part 10, respectively.

[0127] It is to be noted that all embodiments with a concrete thread, which introduce the load that is to be transferred into the concrete via a bonding mechanism, can likewise be embodied with a composite anchor, which transfers the load into the concrete via a composite mass. It is furthermore to be noted that the above-described embodiments are to be considered to be purely exemplary and as not limiting the invention, and that the described features can be significant in any combination.

LIST OF REFERENCE NUMERALS

[0128] 10 mounted part [0129] 12 mounting substrate [0130] 14 anchor [0131] 16 elongate hole [0132] 20, 22, 24, 26 fields of the GUI [0133] 28 metric thread [0134] 30 washer [0135] 32 nut [0136] 34 anchor sleeve [0137] 36 threaded rod [0138] 38 external thread [0139] 40 first anchor sleeve [0140] 42 second anchor sleeve [0141] 44 screw [0142] 46 head