BS 6319-3-1990 Testing of resin and polymer cement compositions for use in construction - Methods for measurement of modulus of elasticity in flexure and flexural strength《建筑用合成树脂胶.pdf

1、BRITISH STANDARD BS6319-3: 1990 Testing of resin and polymer/cement compositions for use in construction Part3: Methods for measurement of modulus of elasticity in flexure and flexural strengthBS 6319-3:1990 This British Standard, having been prepared under the directionof the Cement, Gypsum, Aggreg

2、ates and Quarry Products Standards Policy Committee, was published under the authorityof the Board of BSI andcomes intoeffect on 31 December 1990 BSI 03-1999 First published January1983 Second edition December1990 The following BSI references relate to the work on this standard: Committee reference

3、CAB/17 Draft for comment89/14067DC ISBN 0 580 19184 2 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Cement, Gypsum, Aggregates and Quarry Products Standards Policy Committee (CAB/-) to Technical Committee CAB/17, upon which the followi

4、ng bodies were represented: British Adhesives and Sealants Association British Cement Association British Railways Board Building Employers Confederation Cement Admixtures Association Concrete Repair Association Concrete Society County Surveyors Society Department of the Environment (Building Resear

5、ch Establishment) Department of Transport Department of Transport (Transport and Road Research Laboratory) Federation of Civil Engineering Contractors FeRFA Institution of Highways and Transportation Institution of Structural Engineers Plastics and Rubber Institute Sprayed Concrete Association Amend

6、ments issued since publication Amd. No. Date CommentsBS6319-3:1990 BSI 03-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Definitions 1 3 Principles 1 4 Apparatus 1 5 Test specimens 2 6 Procedure for measuring modulus of elasticity in flexure 2 7 Calculation of

7、 modulus of elasticity in flexure 3 8 Procedure for measuring flexural strength 3 9 Calculation of flexural strength 3 10 Test report 3 Publication(s) referred to Inside back coverBS6319-3:1990 ii BSI 03-1999 Foreword This Part of BS6319 has been prepared under the direction of the Cement, Gypsum, A

8、ggregates and Quarry Products Standards Policy Committee. It supersedes BS6319-3:1983 which is withdrawn. This Part describes methods for measurement of modulus of elasticity in flexure and flexural strength and is one of a series of Parts describing methods for measuring basic physical properties o

9、f resin based and polymer modified materials. In this revision of the1983 edition, flexural strength is now measured under a four point loading system on longer specimens and a new test for modulus of elasticity in flexure using the same loading system has been added. This Part of BS6319 should be r

10、ead in conjunction with Part1which provides general information and describes a method for preparing test specimens. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a

11、British Standard does not of itself confer immunity from legal obligations. In particular, attention is drawn to the Health and Safety at work etc. Act 1974. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1 to4, an inside back cover and a back cov

12、er. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table ontheinside front cover.BS 6319-3:1990 BSI 03-1999 1 1 Scope This Part of BS6319 describes methods for the measurement of modulus of elasticity in flexure a

13、nd flexural strength of specimens of polymer based mortars and polymer/cement based mortars in the form of rectangular prisms. These methods are not applicable to unfilled systems. NOTE 1The procedure described in BS2782: Method335A is suitable for unfilled systems. NOTE 2The titles of the publicati

14、ons referred to in this standard are listed on the inside back cover. 2 Definitions For the purposes of this Part of BS6319 the definitions in BS6319-1 apply, together with the following. 2.1 elastic modulus ratio of stress to corresponding strain below the proportional limit, where the proportional

15、 limit is the greatest stress which a material is capable of supporting without any deviation from the proportionality of stress to strain (Hookes law) 2.2 modulus of elasticity in flexure elastic modulus determined from the relationship between load and the deflection induced by that load in a simp

16、le freely supported beam NOTEAccording to the classical theory of pure bending the deflection () may be expressed in terms of the curvature according to the following relationship: where K is a constant depending upon the configuration of loading. For a beam in four point bending and loaded at the t

17、hird points, K has a value of L is the span of the beam between the supporting rollers. The curvature may be expressed as: where M is the applied bending moment at the section considered; E is the elastic modulus; I is the second moment of area of the section. Hence the modulus of elasticity in flex

18、ure (E) is given by: 2.3 secant modulus in flexure modulus of elasticity in flexure determined from the slope of a particular line on the load versus deflection relationship. This line passes through the origin and a point on the curve corresponding to the deflection necessary to cause a specified s

19、train in the extreme tensile fibre of the beam at the section considered NOTETo determine the deflection of a beam corresponding to a specified strain on the extreme tensile fibre, use may be made of the relationship: where D is the depth of the rectangular specimen;1 r - M EI - = (3) (4) (5) 1) The

20、 capacity of a testing machine is suitable when the expected load at failure of the specimen lies above the lower one-fifth of the range of the machine being used. EK M I - L 2 = b) for specimens more than25mm wide:12.0 times the width of the specimen 0.04 times the width. The loading rollers shall

21、be located at the third span points between the supporting rollers and shall be free to rotate in the vertical plane through their axes. Load shall be applied through a steel spreader beam spanning over the two loading rollers and at a point mid-way between them. The parallelism tolerance for the ho

22、rizontal axis of one supporting roller with respect to the horizontal axis of the second supporting roller as datum shall be0.04mm wide. NOTEParallelism may be achieved by allowing one of the supporting rollers to be free to rotate in the vertical plane through its vertical axis. 4.2 Moulds, complyi

23、ng with BS6319-1 and of a size to produce rectangular prisms in accordance with clause5 of this standard. 4.3 Deflection transducer, capable of continuously monitoring the central deflection of the beam to an accuracy of0.01mm. 5 Test specimens 5.1 Dimensions of specimens Specimens shall be rectangu

24、lar prisms of size25mm 25mm 320mm unless the material contains an aggregate that, when sampled in accordance with BS812-1, will not pass through a test sieve of5mm aperture size complying with BS410. For such materials the width and depth of the prisms shall be at least5.0times the nominal size of t

25、he smallest aperture of a sieve complying with BS410 through which90% of the aggregate will pass. The length to width ratio of the prisms shall be13 : 1. 5.2 Preparation of specimens Prepare the specimens, including the conditioning, proportioning and mixing of materials, and the conditioning and fi

26、lling of moulds in accordance with BS6319-1. 6 Procedure for measuring modulus of elasticity in flexure 6.1 Number of specimens Test a minimum of three specimens at a time from each batch of material for each prescribed set of test conditions. 6.2 Testing 6.2.1 Temperature Carry out the test at20 1

27、C unless, for a specific purpose, an alternative temperature is deemed more appropriate. Maintain the test specimens at the test temperature for not less than16h before testing commences. 6.2.2 Placing the specimen in the testing machine Wipe clean the bearing surfaces of the rollers and the sides o

28、f the specimen to remove any loose grit or other material. Locate the specimen symmetrically in the equipment for the determination of flexural modulus with the upper face, as cast, parallel to the movement of the testing machine crosshead and with the two moulded faces perpendicular to the upper fa

29、ce, in contact with the metal rollers. 6.2.3 Loading Apply the load without shock and at a uniform rate while continuously monitoring the deflection of the tensile face at mid-span. The rate of deflection shall be1mm/min. The maximum load, N 1 , to be applied should be one-third of that necessary to

30、 cause failure in the flexural strength test described in clause8. In the absence of such information, the maximum load, N 1 , to be applied should be that necessary to cause a strain on the extreme tensile fibre of0.0022for polymer mortars or0.00022for polymer/cement mortars. Record the applied loa

31、d, N 1 . Smoothly remove and re-apply the load at least twice to ensure that the specimen and rollers are well seated and that the transducer is indicating consistently. If the individual deflections are not within a range of 10% of their mean value at N 1 , centre the test specimen again and repeat

32、 the procedure. If it is not possible to reduce the differences to within this range, do not proceed with the test on that specimen. Select another specimen from the same batch and continue until three acceptable specimens have been found. Zero the transducers (or the recorder) while the specimen is

33、 under a load, N 2 , approximately10% of that previously applied. Measure the eight changes in deflection as the load is increased and decreased four times between loads N 2and N 1 .BS 6319-3:1990 BSI 03-1999 3 7 Calculation of modulus of elasticity in flexure Calculate the secant modulus, E, (in GN

34、/m 2 ) of each specimen using the following equation: where P is the difference between the two levels of applied load (N 2 N 1 ) (in kN); L is the span of the specimen (in mm); B is the breadth of the specimen (in mm); D is the depth of the specimen (in mm); is the mean of the eight deflection chan

35、ges (inmm). Calculate the mean secant modulus for a minimum of three specimens originating from the same batch and express the value to the nearest0.1GN/m 2 . 8 Procedure for measuring flexural strength 8.1 Number of specimens Test a minimum of four specimens at a time from each batch of material fo

36、r each prescribed set of test conditions. 8.2 Testing 8.2.1 Temperature Control the temperature in accordance with6.2.1. 8.2.2 Placing the specimen in the testing machine Place the specimen in accordance with6.2.2. 8.2.3 Loading Apply the load without shock and at a uniform rate such that the specim

37、en fractures in60 30s. Measure the deflection of the specimen at mid-span during loading. NOTE 1A rate of platen movement1 mm/min to5mm/min will usually be appropriate. Record the maximum load applied. Measure the breadth and depth of the specimen at the point of fracture to the nearest0.1mm. If the

38、 line of fracture occurs between a supporting and loading roller, do not use the result for calculating the flexural strength but declare the result in the test report. Conduct repeat tests at the same rate of loading. NOTE 2If the deflection before fracture exceeds one-fifteenth of the span of the

39、specimen, the test should be discontinued on the grounds of insufficient rigidity of the material for a meaningful value of flexural strength to be measured. 9 Calculation of flexural strength Calculate the flexural strength, u , (in N/mm 2 ) of each specimen using the following equation: where W is

40、 the maximum load recorded prior to fracture (inN); L is the span of the specimen (inmm); B is the breadth of the specimen at its point of fracture (inmm); D is the depth of the specimen at its point of fracture (inmm). Calculate the mean flexural strength obtained for a minimum of four specimens or

41、iginating from the same batch and express the value to the nearest0.2N/mm 2 . NOTEIf12or more specimens are tested, a standard deviation may be calculated and recorded. 10 Test report 10.1 The following information shall be included in the report on a test for modulus of elasticity in flexure and on

42、 a test for flexural strength: a) date and site of specimen preparation; b) date of test; c) ambient conditions during the preparation, curing and testing of the specimens and their age when tested; d) a complete identification of the material tested including type, source, manufacturers code number

43、s and history; e) type of test machine used. 10.2 The following information shall be included in the report on a test for modulus of elasticity: a) cross-sectional area at the centre of the test specimen; b) upper (N 1 ) and lower (N 2 ) load levels used in the testing cycle; c) mean deflection; d)

44、secant modulus of elasticity of each test specimen; e) arithmetic mean secant modulus of elasticity; f) type of transducer used. (6) E 23PL 3 108 BD 3 - = (7) u WL BD 2 - =BS6319-3:1990 4 BSI 03-1999 10.3 The following information shall be included in the report on a test for flexural strength: a) n

45、ominal sizes of each specimen prior to testing and the dimensions at the site of any fracture as a result of testing; b) flexural strength of each specimen; c) arithmetic mean flexural strength; d) breaking loads, including those results excluded from the calculations because of the location of the

46、fracture; e) details of specimens excluded from the results due to excessive deflection (see note2to8.2.3).BS 6319-3:1990 BSI 03-1999 Publication(s) referred to BS410, Specification for test sieves. BS812, Testing aggregates. BS812-1, Methods for determination of particle size and shape. BS1610, Mat

47、erials testing machines and force verification equipment. BS1610-1, Specification for the grading of the forces applied by materials testing machines. BS2782, Methods of testing plastics. BS2782-3, Mechanical properties. BS2782:Method335A, Determination of flexural properties of rigid plastics. BS63

48、19, Testing of resin compositions for use in construction. BS6319-1, Method for preparation of test specimens. BS 6319-3: 1990 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards. It presents the UK v

49、iew on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions BritishStandards are updated by amendment or revision. Users of BritishStandards should make sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve the quality of our products and services. We would be grateful if anyone finding an inaccuracy or ambiguity while using this BritishStandard would inform the Secretary of the technical committee respons