GOST R 56731-2015
GOST R 56731−2015 mechanical Anchors for fastening in concrete. Test methods
GOST R 56731−2015
NATIONAL STANDARD OF THE RUSSIAN FEDERATION
MECHANICAL ANCHORS FOR FASTENING IN CONCRETE
Test methods
Anchors for use in concrete. Test methods
OKS 77.140.01
Date of introduction 2016−06−01
Preface
1 DEVELOPED by the research, design and technological Institute of concrete and reinforced them… Gvozdev, JSC SIC «Construction», with the participation of the Central research Institute of building constructions named.In.Kucherenko
2 SUBMITTED by the Technical Committee for standardization TC 465 «Construction"
3 APPROVED AND put INTO EFFECT by the Federal Agency for technical regulation and Metrology dated November 19, 2015 N 1895-St
4 INTRODUCED FOR THE FIRST TIME
Application rules of this standard are established in GOST R 1.0−2012 (section 8). Information about the changes to this standard is published in the annual (as of January 1 of the current year) reference index «National standards» and the official text changes and amendments — in monthly information index «National standards». In case of revision (replacement) or cancellation of this standard a notification will be published in the upcoming issue of the monthly information index «National standards». Relevant information, notification and lyrics are also posted in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet (www.gost.ru)
1 Scope
1.1 this standard specifies test methods for mechanical anchors that are installed in a ready base of heavy concrete.
1.2 the Standard does not apply to testing glue and plastic anchors.
1.3 this Standard specifies requirements for methods of testing and does not contain requirements for the evaluation of their bearing capacity.
2 Normative references
This standard uses the regulatory references to the following standards:
GOST 12.1.004−91 System safety standards. Fire safety. General requirements
GOST 12.2.003−91 System safety standards. Equipment production. General safety requirements
GOST 8267−93 Crushed stone and gravel from dense rocks for construction works. Specifications
GOST 10178−85 Portland cement and Portland slag cement. Specifications
GOST 10180−2012 Methods for determining the strength of control samples
GOST 17624−2012 Concrete. Ultrasonic method of strength control
GOST 18321−73 Statistical quality control. Methods of random selection of piece products
GOST 26633−2012 Concrete is heavy and fine-grained. Specifications
GOST 22690−2015 Concrete. Determination of strength by mechanical methods of nondestructive testing
GOST 28570−90 Concrete. Strength determination methods on samples taken from structures
GOST 31108−2003 Cements for General construction. Specifications
GOST R 51254−99 Tool mounting normalized tightening threaded connections. Keys torque. General specifications
Note — When using this standard appropriate to test the effect of reference standards in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet or in the annual information index «National standards» published as on January 1 of the current year, and the editions of the monthly information index «National standards» for the current year. If replaced with a reference standard, which was given an undated reference, then it is recommended to use the current version of this standard, taking into account all enabled in this version modifications. If replaced with a reference standard, which is given a dated reference, it is recommended to use the version of this standard referred to above by year of approval (acceptance). If after approval of this standard in the reference standard, which is given a dated reference, a change affecting a provision to which reference, the provision is recommended to be applied without taking into account this change. If the reference standard is cancelled without replacement, the position in which reference is made to him, recommended to be used in part not affecting this link.
3 Terms, definitions and symbols
3.1 this standard applies the following terms with respective definitions:
3.1.1 anchor: Constructive element intended for fastening elements for various purposes to the base, which is either laid in the ground, or later installed in finished ground and used to transfer force on the base.
3.1.2 mechanical anchor: Steel anchor in which the transmission of the efforts from steel element to the base via a direct mechanical interaction with the base (propping it stops, gearing, friction, etc.);
3.1.3 push-in anchor: the Mechanical anchor, the securing of which the base is carried out by forcing the spacers into the drilled hole.
3.1.4 anchor with control of tightening torque: Spacer anchor, whose thrust is created by a controlled torque acting on the screw, bolt or nut.
3.1.5 the anchor with the control of movement: Push-in anchor, whose thrust is achieved by the controlled movement of the cone of wedging relation to the bushing.
3.1.6 anchor with widening: the Mechanical anchor, the securing of which the base is carried out by the device widening in the body of the base and the mechanical locking in this anchor.
3.1.7 anchor-screw: Mechanical anchor, anchoring at the base of which is carried out by screwing in the drilled hole with the cutting edges of a carving in the base material.
3.2 this standard applies the following designations: — distance from the axis of the anchor to the edge of the base;
— distance from the axis of the anchor to the edge of the base in the direction of the shearing force;
— distance from the axis of the anchor to the edge of the base in a direction perpendicular to the action of shear forces;
— the minimum allowable distance from the edge;
— diameter of anchor bolt or thread diameter;
— the diameter of the hole in attached parts;
— outer diameter of the anchor;
— the thickness of the base;
effective embedment depth;
— the minimum thickness of the concrete element;
— distance (pitch) between axes of anchors;
— the minimum allowable distance (step) between axes of anchors;
— tightening torque when installing the anchor;
— thickness of attached parts.
4 General provisions
4.1 the results of the tests prescribed in this standard, used for setting or monitoring compliance with regulatory documents and technical documentation of the mechanical characteristics of anchors and their installation in concrete base.
4.2 Under the mechanical characteristics of anchors, as defined in this standard, means:
strength on the tension;
— shear strength;
— move the anchor when digging and shear, respectively.
4.3 the Influence of deviations of the settings of the anchor from the specified manufacturers, and also damage the concrete base set in the course of the following tests:
— test in concrete with a crack;
— test when exceeding the torque anchor;
— test near the valve base (for anchors with widening);
— data on size and anchor design.
4.4 tests On selected samples of anchors, representing the finished product manufacturer. Scope of supply of anchors must comply with the technical documentation for the submitted sample.
4.5 Anchors with internal thread is allowed to provide for testing without such fasteners, as screws, threaded studs or nuts, but the manufacturer of the anchor should specify the necessary to use screws, threaded studs or nuts.
4.6 Samples should be selected at random according to GOST 18321. Sampling confirmed by the certificate.
4.7 Together with the anchor on the testing set of technical documentation in the following scope:
— information on the manufacturer;
— installation guide anchor;
— other documentation provided for national standards or certification body.
4.8 Before testing should be conducted to identify the samples presented in the following order:
— visual inspection to establish compliance of the anchor of technical documentation;
— to carry out control of compliance marking, marked on the anchor, technical documentation;
— to measure the size of the anchor and to match their technical documentation.
4.9 the Tested anchors, including not brought to the ultimate limit state of strength, can not be reused, recycling is performed by the instructions of the technical documentation of the manufacturer.
5 Requirements for test conditions and equipment
5.1 testing Conditions
5.1.1 Test should be carried out at an ambient temperature of +10°C to +40°C and a humidity of 70%.
5.1.2 the base Concrete should be kept at a positive ambient temperature before the test of anchors is not less than 7 days.
5.2 Requirements for concrete
5.2.1 For test should be applied heavy concrete in accordance with trebovaniyami 26633 manufactured at Portland cement according to GOST 10178, GOST 31108.
5.2.2 as filler for concrete, you should apply granite crushed stone according to GOST 8267, particle size 5−20 mm.
5.2.3 Concrete should be made with water cement ratio not more than 0.75, the consumption of cement shall be not less than 240 kg/m.
5.2.4 the Average strength of concrete of the base, corresponding to the accepted class of concrete for testing shall meet the range specified in table 1.
Table 1 — Range strength of concrete
| Class of concrete (In) | The range of medium strength ®, MPa |
Class of concrete (In) | The range of medium strength ®, MPa |
| 15 | 12−19 |
40 | 40−14 |
| 20 | 20−24 |
45 | 45−19 |
| 25 | 25−29 |
50 | 50−54 |
| 30 | 30−34 |
55 | 55−59 |
| 35 | 35−39 |
60 | 60−70 |
5.2.5 the strength of the concrete Foundation should be set by standard samples-cubes according to GOST 10180 in an amount of not less than 3, produced during the concreting of the base. Samples must be adhered to and to harden in conditions of hardening grounds for testing.
5.2.6 testing of standard samples according to GOST 10180 should be carried out during testing of anchors. You can also determine the strength of concrete by sampling according to GOST 28570 or by non-destructive testing according to GOST 22690 and GOST 17624.
5.2.7 the Size and design of the Foundation for the testing of anchors shall satisfy the following requirements:
— when testing at the base with a crack: the base should have a rectangular shape in plan, of a thickness not less than 2but not less than 100 mm. Cracks should be placed along one of the sides of the base and have a uniform opening width over the height of the sample.
— when testing in the concrete without cracking the base should not have reinforcement. Use constructive reinforcement, the distance from the axis of the anchor to valve stem shall be not less than 2.
5.2.8 the layout of the reinforcement shall be displayed on the surface of the sample to comply with the conditions for setting of anchors.
5.2.9 Testing of anchors should be in the age of the concrete at least 28 days. Allowed to test at the age that is different from 28 days, in compliance with the requirements
5.3 installation Requirements anchor
5.3.1 Anchors must be installed in the base in accordance with the technical documentation of the manufacturer.
5.3.2 the Hole in the base of the anchor should be placed on a smooth surface (bottom of the molding) and run perpendicular to the surface. The dependence of the diameter of the cutting edges of the drill diameter is given in Annex B.
5.3.3 to apply the equipment for drilling and installation according to the technical documentation of the manufacturer. In the absence of manufacturer’s instructions for the type of equipment allowed to use any tool, while the nominal dimensions of the tip of the drill shall conform to the manufacturer’s instructions.
5.4 hardware Requirements for testing
5.4.1 the Equipment should provide a smooth application of the load, with a constant rate of change of force or displacement, and to provide a simultaneous fixation of the load and displacement of the anchor. It is also allowed to apply the load steps.
5.4.2 equipment for testing should not have detrimental effect on the concrete in the installation of the anchor, for this distance in light between the supports snap and the axis of the anchor shall be not less than 2(when tested in tension, and shear without the influence of the base) or 2
(when tested in shear on the chipping edges of the base).
5.4.3 Schematic of test benches for testing the tension and shear given in Appendix A.
5.4.4 During the tests on the tension load to the anchor should be attached coaxially with the anchor. The diameter of the hole in attached parts shall conform to the values given in table A. 1.
5.4.5 When subjected to a shear load shall be applied parallel to the surface of the concrete base. Sleeve for shear testing shall be made of hardened steel and have rounded edges of 0.4 mm (see figure A. 3). The height of the sleeve in the zone of contact with the anchor must be no less than the outer diameter of the anchor. The inner diameter of the liner should conform to the dimensions shown in table A. 1. To reduce friction between the plate sleeve and the concrete base you should use a gasket made of PTFE.
5.5 Requirements for measuring instruments
5.5.1 For testing, use of certified means of measurement, last calibration and verification in the prescribed manner.
5.5.2 measurement Error of the load must not exceed 2% of the bearing capacity of the anchor according
5.5.3 measurement Error of the displacements of the anchor should not exceed 0,02 mm.
5.6 safety Requirements when testing
5.6.1 When testing should ensure compliance with safety requirements according to GOST 12.1.004 and GOST
5.6.2 In the installation of the anchors should comply with the security requirements stipulated in the technical documentation of the manufacturer.
5.6.3 Location of the test site, the equipment and equipment must guarantee the safety of the personnel participating in the test.
5.6.4 Testing should be stopped in the following cases:
— increased pressure in hydraulic equipment above the values permitted the technical documentation on the equipment;
— pressure drop in hydraulic equipment that is not associated with the nature of the anchors under load;
— detection of damage or malfunction of equipment and measuring instruments.
5.6.5 All work associated with removal of the detected defects shall be performed only after complete unloading.
6 Rules for testing
6.1 the essence of the method
6.1.1 the method of testing anchors on the tension and shear in concrete without cracks and with cracks is to measure the values of the test load corresponding to one of limiting States, and measuring displacement of the anchor during loading.
6.1.2 Limit state of strength when tested in tension.
— debonding of the anchor with the concrete, causing it to slide or pulling;
— puncturing of the concrete base with the formation of a cone of concrete;
— fracture of the anchor steel at the effort gap.
6.1.3 Limit state of strength when tested in shear.
— fracture of the anchor steel at the achievement of shear forces;
— puncturing of the concrete base for an anchor.
6.2 Preparation and test
6.2.1 In preparation for the test, the anchor and snap-in must be installed in accordance with the requirements of 5.2−5.3.
6.2.2 When testing the spacing of nearby anchors and the distance from the axis of the anchor to the edge of the base must be large enough to prevent the formation of the puncturing cone with angle of 120°.
6.2.3 testing of the anchors with control of the tightening torque, use the torque (torque) keys according to GOST 51254*, the error shall not exceed 5% of the tightening torque. After 10 min tightening should reduce the time to 0.5.
________________
* Probably, the error of the original. Should read: GOST R 51254. — Note the manufacturer’s database.
6.2.4 Anchors that does not require screws according to the technical documentation of the manufacturer, should not be tightened before testing.
6.2.5 nominal diameter of the drill should be taken with the level tolerances in accordance with table B. 1. In order to comply with these requirements, you should check the diameter of the drill after every 10 drill holes.
6.2.6 Test is carried out for a series of anchors.
6.2.7 Duration of loading of the anchor should be 1 to 3 min. under continuous loading and 15−20 min with a step-loading exposure time of 2−3 min at each step.
6.2.8 test results for each build anchor chart «load — displacement».
6.3 Test on the tension
6.3.1 Loading of the anchor is performed until it reaches one of the limit States according
6.3.2 When tested in the base crack testing is carried out in such sequence. With wedges installed in predrilled holes, forming a crack in the base according to the scheme in figure A. 5, and then remove the wedges, drill a hole and control the formation of cracks in the hole. The crack must pass through the hole throughout its depth. Then set the anchor in place of formation of a crack according to the manufacturer’s instructions. Perform opening cracks and carry out tests of anchor.
6.3.3 the test should measure the width of cracks in the vicinity of the anchor.
6.3.4 testing of the anchor in the corner of the concrete element equipment for testing shall be arranged so as to prevent unrestricted destruction of the concrete in the corner (see figure 1).
Figure 1 — Example of equipment for tensile testing of anchors installed in the corner
1 — base; 2 — test anchor
Figure 1 — Example of equipment for tensile testing of anchors installed in the corner
6.4 Test shear
6.4.1 the Anchor set with no gap between the sleeve and the concrete Foundation. The test is carried out to destruction in accordance with 5.4.5 and 6.2 and the diagram in figure A. 2.
6.4.2 during the test record the value of the displacement of the anchor relative to the base along the direction of shear loading.
6.5 Test for excess torque
6.5.1 Test performed on a single anchor at the base without cracking.
6.5.2 tightening Torque applied with a torque wrench with the torque until the cessation of growth, but not more than 1.3. Perform exposure 10 min, control torque, and performing the lift anchor point to 1.3
.
6.5.3 After tightening perform a test on the tension
6.6 Test check of minimum spacing and edge distances
6.6.1 Test performed by the tightening torque of the anchors.
6.6.2 Performing the test group of two anchors installed near edge of base:
— with minimum edge distance and corresponding centre distance
;
— with a minimum center-to-center distance and the edge distance
.
6.6.3 Distance between anchors of adjacent groups should be at least 3.
6.6.4 the size of the anchor plates should be used according to Annex A (see figure A. 4). Diameter of clearance holes, made in the anchor plate shall meet the values given in table A. 1 of Annex A. the Thickness of the plate is taken to be equal
. Permitted instead of anchor plates to apply a square washer with a width 4
and a thickness
.
6.6.5 fastening anchors should be performed alternately with the step of the torque of 0.2. After each step, inspect the concrete surface for cracks. The tightening torque should be increased prior to the termination of its growth.
6.6.6 Should fix the speed in one step load for each anchor.
6.6.7 During the test, record the torque at which the first crack is formed and the maximum torque.
6.7 Test the effect of reinforcing the base
6.7.1 Test to determine the effect of the reinforcement base to perform on single anchors in 6.3.1, subject to the following provisions.
6.7.2 Perform the hole with the trim valves base on the effective depth of the anchor 1 mm (as shown in figure 2), and then perform the test to failure.
Figure 2 — diagram of the anchor testing under the influence of the reinforcement of Foundation
Figure 2 — diagram of the anchor testing under the influence of the reinforcement of Foundation
6.8 Test of a multi-cycle tensile
6.8.1 the Test is performed in the base without cracking in axial tension on the action repetitive (pulsating) load. The scheme of load application is presented in figure A. 1.
6.8.2 Tensile load on the anchor is applied cyclically with a frequency of 5−7 Hz. The number of loading cycles from to
take up to 10
or to failure of the anchor.
6.8.3 Measurement of displacement of the anchor is performed by the first cycle of loading to a value , then the measurement is performed continuously or after 1, 10, 10
, 10
, 10
, 10
cycles of loading.
6.8.4 After completion of the load cycles the anchor should offload, to measure the residual displacement and to perform a test on the tension
7 the Rules of registration of test results
The test report must include the following information:
7.1 General information
— Description and type of anchor;
the anchor identification (dimensions, materials, coating, production method);
— the name and address of the manufacturer;
— the name and address of the testing laboratory;
— date of the test;
— the person responsible for conducting the test;
— type of test (e.g. tensile test, shear);
— the number of trials.
— equipment for test with drawings or photographs.
7.2 characteristics of the base for testing
— The composition of the concrete. The indices of concrete mix before laying (density, mobility);
— date of manufacture;
— dimensions of control samples and/or cores (if applicable), the value of compressive strength at time of testing (individual results and average value);
— the dimensions of the base for testing and the location of the molding surface;
— the nature and location of the reinforcement of Foundation.
7.3 Installation of anchors
— Information about the location of the anchor (e.g. on the molding surface of the concrete base);
— the distance between adjacent anchors and the edge of the concrete base;
— tool required for installation of the anchor, e.g. impact drilling tool, rotary hammer, other equipment, e.g. torque wrench with torque;
— the type of tip drill, marking of the manufacturer and the measured size of the tip of the drill bit corresponding to the effective diameter , carbide-tipped insert.
— data on direction of drilling;
— information about purging holes;
— the depth of drilled holes;
— the actual installation depth of the anchor;
— the width of crack when installing the anchor (where applicable);
— tightening torque and other parameters to control the installation, such as the depth of penetration of an expansion element in the anchors, the control move;
— move the anchor upon application of torque (if measured);
— the type of screws and nuts;
— the length of thread involved (as appropriate).
7.4 Recorded figures
— Parameters of load application (the time to maximum load, moving speed);
a plot of the displacement of the anchor from the applied load;
— crack width during loading of the anchor (where applicable);
— breaking load;
— type of fracture of the anchor;
— the shape and size of the cone puncturing concrete substrate at failure (as appropriate);
— information about the trials of a group of anchors: the mechanism of destruction, the possible formation of cracks between the anchors;
— information about tests of the anchor in contact with pin valve: positioning the anchor relative to the rods, the size broadening.
7.5 the contents of the Protocol may be supplemented, depending on volume and circumstances test.
Annex a (informative). Schematic diagrams of the test rigs
Appendix A
(reference)
Figure A. 1 — schematic diagram of the test stand anchor on the tension
1 — the Jack with a force sensor (pressure); 2 — strength frame; 3 — bearing power frame; 4 — a universal gripping device with traction; 5 — joint; 6 — registration device of the control parameters (force, displacement); 7 — base; 8 — subject anchor; 9 — guide unit on an independent tripod; 10 — thin wire; 11 — travel indicator on an independent tripod
Figure A. 1 — schematic diagram of the test stand anchor on the tension
Figure A. 2 — schematic diagram of the test stand shear
1 — the Jack with a force sensor (pressure); 2 — strength frame; 3 — pole, fixed to floor power; 4 — a universal gripping device with traction; 5 — joint; 6 — registration device of the control parameters (force, displacement); 7 — base; 8 — subject anchor; 9 — emphasis; 10 — clamp; 11 — a travel indicator on an independent tripod; 12 — power floor
Figure A. 2 — schematic diagram of the test stand shear
Figure A. 3 — Sleeve for shear testing
1 — base; 2 — a casing (liner); 3 — equipment for tests; 4 — chamfer
Figure A. 3 — Sleeve for shear testing
Table A. 1 — Diameter of the sleeve for testing
| In millimeters | ||||||||||||
The outside diameter of the anchor |
6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 22 | 24 | 27 | 30 |
The diameter of the hole in the world |
7 | 9 | 12 | 14 | 16 | 18 | 20 | 22 | 24 | 26 | 30 | 33 |
Figure A. 4 — Test to check the minimum spacing and edge distances
1 — base; 2 — base plate; 3 — anchor
Figure A. 4 — Test to check the minimum spacing and edge distances
Figure A. 5 — Test basis with crack
1 — anchor;
2 — the wedge;
3 — the indicator measure the width of the crack opening
Figure A. 5 — Test basis with crack
Appendix B (mandatory). Requirements for drilling installation holes for the anchors
Appendix B
(required)
Drill (drills) to complete the holes for the anchors should enable the implementation of the locating holes of the specified depth the specified nominal diameter. The actual drill diameter is determined by the maximum dimensions of the cutting part (see figure B. 1) shall comply with the requirements of table B. 1. The actual drill diameter is measured with accuracy up to 0.05 mm. the Required level of tolerances drill diameter is determined depending on the kind of tests, for unspecified cases were subject to drill with average tolerances.
Table B. 1 — the Diameter in millimeters
| Nominal diameter of the drill |
The actual diameter of the drill | ||
| The minimum level of tolerances |
The average level of tolerance | The maximum level of tolerance | |
| 6 |
6,05−6,2 | 6.2 and 6.3 | 6.35 mm-6,4 |
| 8 |
8,05−8,2 | 8,25−8,35 | The 8.4-to 8.45 |
| 10 |
Of 10.05 to 10.2 | 10,25−10,35 | 10,4-of 10.45 |
| 12 |
12,1−12,2 | 12,25−12,35 | 12,45−12,5 |
| 14 |
14,1−14,2 | 14,25−14,35 | And 14.45−14.5 mm |
| 15 |
15,1−15,2 | 15,25−15,35 | 15,45−15,5 |
| 16 |
16,1−16,2 | 16,25−16,35 | 16,45−16,5 |
| 18 |
18,1−18,2 | 18,25−18,35 | 18,45−18,5 |
| 20 |
20,1−20,2 | The 20.3 and 20.4 | 20,5-of 20.55 |
| 22 |
22,1−22,2 | Of 22.3 and 22.4 | 22,5−22,55 |
| 24 |
24,1−24,2 | With 24.3−24.4 per | A 24.5−24,55 |
| 25 |
25,1−25,2 | 25,3−25,4 | 25,5−25,55 |
| 27 |
27,1−27,2 | 27,3−27,4 | 27,5−27,55 |
| 30 |
30,1−30,2 | 30,3−30,4 | 30,5−30,55 |
| 32 |
Of 32.15−32,25 | 32,35−32,5 | A 32.6−32.7 per |
| 35 |
35,15−35,25 | 35,35−35,5 | 35,6−35,7 |
| 37 |
The 37.15−37,25 | 37,35 is 37.5 | Of 37.6−37,7 |
| 40 |
40,15−10,25 | Of 40.4−40.6 per | 40,7 of 40.8 |
Figure B. 1 — Reference drill sizes for installation holes for anchors
Figure B. 1 — Reference drill sizes for installation holes for anchors
Annex b (informative). Test digging in the cyclic crack opening
The App
(reference)
V. 1 the Test is carry out in such sequence. Form the crack in the base with the cage reinforcement (see figure V. 1). Install the anchors according to the manufacturer’s instructions in the closed crack and run the crack opening until it reaches the values , and then apply tensile load to the anchor and carry out a cyclical opening cracks with number of cycles equal
.
B. 2 Frequency of disclosure and closing of the cracks is taken in the range 0.1−0.3 Hz.
B. 3 Range of crack take to
. For this loading the crack opening pick up empirically.
Q. 4 a Tensile force in the anchor during the test shall not differ from the initial by more than 5%.
B. 5 the test results build a graph of the displacement of the anchor from the tensile force. For this purpose, the tests are carried out in a continuous non-moving anchor or after 1, 2, 5, 10, 20, 50, 100, 200, 500, 1000 etc. cycle crack.
V. 6 After completion of the cyclic crack anchor should offload, to measure the residual displacement and to perform a test on the tension in 6.3.1 with .
Figure B. 1 — Test base with crack
1 — anchor; 2 — the initiator of the crack; 3 — crack; 4 — valves
Figure B. 1 — Test base with crack
