BS PD CEN TS 15963-2014 Bitumen and bituminous binders Determination of the fracture toughness temperature by a three point bending test on a notched specimen《沥青和沥青混合料 切口试样上用三点弯曲试验.pdf

1、BSI Standards PublicationBitumen and bituminous binders Determination of the fracture toughness temperature by a three point bending test on a notched specimenPD CEN/TS 15963:2014National forewordThis Published Document is the UK implementation of CEN/TS 15963:2014.It supersedes DD CEN/TS 15963:2010

2、, BS 2000-584:2010 which iswithdrawn.The UK participation in its preparation was entrusted by Technical Committee B/510, Road materials, to Subcommittee B/510/19, Bitumen andrelated products.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publica

3、tion does not purport to include all the necessary provisions ofa contract. Users are responsible for its correct application. The British Standards Institution 2014.Published by BSI Standards Limited 2014ISBN 978 0 580 79758 3ICS 91.100.50Compliance with a British Standard cannot confer immunity fr

4、omlegal obligations.This Published Document was published under the authority of theStandards Policy and Strategy Committee on 30 June 2014.Amendments/corrigenda issued since publicationAmd. No. Date Text affectedPUBLISHED DOCUMENTPD CEN/TS 15963:2014TECHNICAL SPECIFICATION SPCIFICATION TECHNIQUE TE

5、CHNISCHE SPEZIFIKATION CEN/TS 15963 April 2014 ICS 91.100.50 Supersedes CEN/TS 15963:2010English Version Bitumen and bituminous binders - Determination of the fracture toughness temperature by a three point bending test on a notched specimen Bitumes et liants bitumineux - Dtermination de la tempratu

6、re de rsistance la fissuration par un essai de flexion 3 points sur un barreau entaill Bitumen und bitumenhaltige Bindemittel - Bestimmung der Bruchwiderstandstemperatur mittels eines Drei-Punkt-Biegeversuches an einem gekerbten Probekrper This Technical Specification (CEN/TS) was approved by CEN on

7、 16 December 2013 for provisional application. The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard. CEN memb

8、ers are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS) until the final decision about the

9、possible conversion of the CEN/TS into an EN is reached. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

10、Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 1

11、7, B-1000 Brussels 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. CEN/TS 15963:2014 EPD CEN/TS 15963:2014CEN/TS 15963:2014 (E) 2 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Principle

12、6 5 Apparatus .6 5.1 Testing apparatus 6 5.2 Test specimen 8 6 Preparation of test samples 9 6.1 Preparation of test samples 9 6.2 Preparation of moulds .9 6.3 Preparation of test specimen 11 7 Procedure to determine the Fracture Toughness temperature TFT. 12 7.1 Number of tests . 12 7.2 Specimen co

13、nditioning 12 7.3 Loading rate and test temperature 12 7.4 Validity of the test results 12 7.5 Fracture Toughness temperature, TFT12 8 Calculation . 12 8.1 Test sample . 12 8.2 Results and temperature 13 8.3 Fracture Toughness temperature, TFT13 9 Expression of results . 14 9.1 Fracture Toughness te

14、mperature, TFT14 9.2 Other properties 14 10 Precision 14 10.1 Repeatability 14 10.2 Reproducibility 14 11 Test report . 15 Annex A (informative) Calculation of Critical Stress Intensity factor . 16 A.1 General . 16 A.2 Terms and definitions 16 A.3 Calculations . 16 Bibliography . 18 PD CEN/TS 15963:

15、2014CEN/TS 15963:2014 (E) 3 Foreword This document (CEN/TS 15963:2014) has been prepared by Technical Committee CEN/TC 336 “Bituminous binders”, the secretariat of which is held by AFNOR. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent ri

16、ghts. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes CEN/TS 15963:2010. According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following countries are bound to announce this Technical Sp

17、ecification: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slove

18、nia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. PD CEN/TS 15963:2014CEN/TS 15963:2014 (E) 4 1 Scope This Technical Specification specifies a method for the determination of the Fracture Toughness temperature, TFT, of bituminous binders by means of a three point bending test on a notc

19、hed binder sample. WARNING The use of this Technical Specification can involve hazardous materials, operations and equipment. This Technical Specification does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this Technical Specificat

20、ion to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. For environmental reasons, it is recommended to limit the use of products, solvents and energy to minimum in order to reduce the emissions to air, water and soil. 2 Nor

21、mative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments

22、) applies. EN 58, Bitumen and bituminous binders - Sampling bituminous binders EN 12594, Bitumen and bituminous binders - Preparation of test samples 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 maximum force F highest force measured durin

23、g the bending test Note 1 to entry: The test is done in the brittle state or close to that, so that the maximum force is considered as the onset of the crack propagation. Note 2 to entry: Force is expressed in newtons (N). 3.2 displacement at maximum force D bending of the test beam from the beginni

24、ng of the test (from the zero point) to the break point Note 1 to entry: Displacement is expressed in millimetres (mm). 3.3 work W area under the force-displacement curve from the beginning of the test to the break of the sample, i.e. at the maximum force Note 1 to entry: Work is expressed in newton

25、smetres (Nm) or in Joules (J). PD CEN/TS 15963:2014CEN/TS 15963:2014 (E) 5 3.4 Fracture Toughness temperature TFTtemperature at which the displacement at the maximum force is 0,3 mm (from the zero point) Note 1 to entry: Fracture Toughness temperature is expressed in degrees Celsius (C). 3.5 initial

26、 stiffness S value calculated as the slope of the tangent of the force-displacement curve at the inflection point Note 1 to entry: See Figure 1. Note 2 to entry: Stiffness is expressed in newtons per millimetre (N/mm). 3.6 zero point intersection of the x-axis and the tangent of the force-displaceme

27、nt curve at the inflection point expressed in millimetres (mm) Figure 1 presents an example of the force versus displacement curve at a temperature T close to TFT. Key X displacement, in millimetres (mm) A maximum force (defined as F) Y force, in newtons (N) B X point at maximum force C tangent at t

28、he inflection point D displacement at maximum force, (D = B - E) E zero point W work as defined in 3.3 I inflection point of F versus displacement Figure 1 Example of a Force versus displacement curve at temperature T (close to TFT) PD CEN/TS 15963:2014CEN/TS 15963:2014 (E) 6 4 Principle The notched

29、 three point bending test is used to measure cracking performance of unmodified and modified bituminous binder samples. The test sample is a beam with a notch in the middle of one side of the beam. The sample is conditioned in a temperature controlled bath. The beam is placed on two supports with th

30、e notch facing downwards and a vertical downward force is applied on the middle of the upper face of the sample. The beam is loaded until failure with a specified displacement rate, whereby force is recorded versus displacement. NOTE 1 The fracture properties of bituminous binders are strongly depen

31、dent on test temperature, loading rate and sample preparation method. NOTE 2 This test is based on the work done by S. Hesp for the Ministry of Transportation in Ontario, Canada 1. 5 Apparatus 5.1 Testing apparatus 5.1.1 Tension-compression device A universal tension-compression device, which is cap

32、able of sustaining a constant, predetermined displacement rate. 5.1.2 Bending rig A bending rig consisting of two cylindrical specimen supports, a cylindrical-nosed shaft to apply the load to the mid-point of the test specimen and a load cell mounted in line with the loading shaft. The dimensions an

33、d tolerances of the loading frame are given in Table 1. 5.1.3 Loading system A loading system, which is capable of applying a rate of displacement of 0,01 mm/s. The specified displacement rate shall fluctuate by no more than 10 % over time. The maximum stroke of the instrument shall be at least 20 m

34、m for this test. 5.1.4 Loading shaft A loading shaft, which is continuous and in line with the load cell and deflection measuring transducer. The T-shape shaft shall have a cylindrical-shaped loading pin in the end. The diameter of the pin shall be (10,0 0,1) mm. 5.1.5 Load cell A load cell having a

35、 minimum capacity of no less than 500 N and an accuracy of 1 % above 5 N with a minimum resolution of at least 100 mN is required. The load cell shall allow the measurement of the force at any time during the test. 5.1.6 LVD-transducer An LVD transducer or other suitable device to measure the deflec

36、tion of the sample is necessary. It shall have a linear range of at least 5 mm with an accuracy of 2 m. The deflection may be measured using this separate transducer or by measuring the vertical movement of the tension/compression device. PD CEN/TS 15963:2014CEN/TS 15963:2014 (E) 7 5.1.7 Specimen su

37、pports Specimen supports which shall consist of two non-corrosive metal half-rounds or cylinders with a diameter of (10,0 0,1) mm that are spaced (100 1) mm apart (cylinder centre point to cylinder centre point). The specimen shall be placed perpendicular to the supports and the loading pin. To faci

38、litate that, two vertical alignment pins of 2 mm to 4 mm in diameter can be provided at the back of each support. A schematic diagram of the sample supports is shown in Figure 2. 5.1.8 Ventilated oven, capable of maintaining a temperature up to 200 C, with an accuracy of 1 C. The specified temperatu

39、re shall only be assessed in the surroundings of the sample (see 6.3). Dimensions in millimetres Key 1 cylindrical loading shaft pin 4 alignment pin 2 specimen (see details on Figure 3) F force applied 3 specimen supports Figure 2 Bending rig Table 1 Measurement and tolerances of the rig Dimension S

40、ize, mm Tolerance, mm Loading shaft pin length 25 2 Loading shaft diameter 10,0 0,1 Specimen support length 25 2 Specimen support diameter 10,0 0,1 Specimen support span 100 1 5.1.9 Temperature measurement device A calibrated temperature transducer capable of measuring the temperature with the accur

41、acy of 0,1 C over the range of - 40,0 C to 0,0 C. The temperature measuring head shall be mounted in the near vicinity of the specimen, at a distance of not more than 25 mm from the middle of the specimen. PD CEN/TS 15963:2014CEN/TS 15963:2014 (E) 8 5.1.10 Liquid bath A liquid bath shall be capable

42、of maintaining the required test temperature near the test specimen within 0,2 C during the isothermal conditioning and the test procedure, enabling to reach the lower temperature required for testing the specimen. Bath liquid shall not affect the properties of the bituminous binder being tested. NO

43、TE 95 % volume ethanol or a 40 % to 50 % mass potassium acetate-water solution has been found to be suitable as a bath liquid. 5.1.11 Data acquisition The data acquisition system shall resolve loads to the nearest 100 mN, record specimen deflection to the nearest 0,5 m, record time to the nearest 0,

44、1 s and temperature around the sample to the nearest 0,1 C. The software shall control the measuring system and record time, load, deflection and temperature during the test. Sampling rate of force and displacement should be at least 0,1 s1(10 Hz). 5.2 Test specimen A test specimen as shown on Figur

45、e 3 is used. The sample is moulded from the bituminous binder to be assessed. Two aluminium inserts are installed at the ends of the mould. The notch is made by installing two sheets of silicone paper into the pre-notched mould frame. NOTE Silicone paper with a weight of 135 g/m2has been found suita

46、ble. Key LBebeam length H specimen height a notch depth L specimen length B specimen thickness b notch thickness LIninsert length Figure 3 Specimen geometry PD CEN/TS 15963:2014CEN/TS 15963:2014 (E) 9 Table 2 Test specimen dimensions and tolerances Dimension Size, mm Tolerance a, mm Beam length, LBe

47、 120,0 0,3 Insert length, LIn 40,0 0,1 Specimen length, L 40,0 0,2 Specimen height, H 25,0 0,5 Specimen thickness, B 12,5 0,3 Notch depth, a 5,0 0,1 Notch thickness, b 2 25 m - aTolerance is related to the mould. 6 Preparation of test samples 6.1 Preparation of test samples The laboratory sample sha

48、ll be taken in accordance with EN 58 and the test samples shall be prepared in accordance with EN 12594. 6.2 Preparation of moulds The moulds for making the samples shall be assembled from aluminium side spacers. On the side spacers and on the bottom a plastic film is glued with an anti-sticking age

49、nt to prevent sticking of the bitumen binder to the mould. Two aluminium inserts are installed in the ends of the mould. The surfaces of the aluminium inserts that are in contact with bitumen should be roughened to ensure good adhesion. A series of such assemblies may be clamped together to make more than one specimen at a time. Figure 4 shows the different parts of the mould. Figure 5 shows a picture of such an example assembly and its parts. PD CEN/TS 15963:2014CEN/TS 15963:2014 (E) 10 Key LBe