1、BRITISH STANDARDBS 2000-533: 2005 BS EN 14771:2005Bitumen and bituminous binders Determination of the flexural creep stiffness Bending Beam Rheometer (BBR)(Identical to IP 533:2005)The European Standard EN 14771:2005 has the status of a British StandardICS 75.140; 91.100.50g49g50g3g38g50g51g60g44g49
2、g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58Licensed Copy: Wang Bin, na, Tue Apr 18 02:38:08 BST 2006, Uncontrolled Copy, (c) BSIBS EN 14771:2005This British Standard was
3、 published under the authority of the Standards Policy and Strategy Committee on 13 January 2006 BSI 13 January 2006ISBN 0 580 46892 5National forewordThis British Standard is the official English language version of EN 14771:2005.The UK participation in its preparation was entrusted to Technical Co
4、mmittee PTI/13, Petroleum testing and terminology, which has the responsibility to:A list of organizations represented on this committee can be obtained on request to its secretary.The Energy Institute, under the brand of IP publishes and sells all parts of BS 2000, and all BS EN petroleum test meth
5、ods that would be part of BS 2000, both in its annual publication “Standard methods for analysis and testing of petroleum and related products and British Standard 2000 parts” and individually.Further information is available from:Energy Institute, 61 New Cavendish Street, London W1G 7AR. Tel: 020 7
6、467 7100. Fax: 020 7255 1472.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the
7、 BSI Electronic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquir
8、ers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK.Summary of pagesThis document co
9、mprises a front cover, an inside front cover, the EN title page, pages 2 to 15 and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsLicensed Copy: Wang Bin, na, Tue Apr 18 02:38:08 BS
10、T 2006, Uncontrolled Copy, (c) BSIEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14771May 2005ICS 75.140; 91.100.50English versionBitumen and bituminous binders - Determination of the flexuralcreep stiffness - Bending Beam Rheometer (BBR)Bitumes et liants bitumineux - Dtermination du module derig
11、idit en flexion - Rhomtre flexion du barreau (BBR)Bitumen und bitumenhaltige Bindemittel - Bestimmung derBiegekriechsteifigkeit - Biegebalkenrheometer (BBR)This European Standard was approved by CEN on 25 March 2005.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stip
12、ulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exis
13、ts in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies
14、 of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STAN
15、DARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2005 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14771:2005: ELicensed Copy: Wang Bin, na, Tue Apr 18 0
16、2:38:08 BST 2006, Uncontrolled Copy, (c) BSIEN 14771:2005 (E) 2 Contents page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Principle5 5 Apparatus .5 6 Preparation of test samples6 7 Procedure .7 8 Calculation8 9 Expression of results 9 10 Precision.9 11 Test report 10 Li
17、censed Copy: Wang Bin, na, Tue Apr 18 02:38:08 BST 2006, Uncontrolled Copy, (c) BSIEN 14771:2005 (E) 3 Foreword This document (EN 14771:2005) has been prepared by Technical Committee CEN/TC 336 “Bituminous binders”, the secretariat of which is held by AFNOR. This European Standard shall be given the
18、 status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2005, and conflicting national standards shall be withdrawn at the latest by November 2005. This European Standard is based on ASTM D 6648-01. According to the CEN/CENELEC Internal
19、 Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlan
20、ds, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: Wang Bin, na, Tue Apr 18 02:38:08 BST 2006, Uncontrolled Copy, (c) BSIEN 14771:2005 (E) 4 1 Scope This European Standard specifies a method for the determination of the flexural creep stif
21、fness of bituminous binders in the range of 30 MPa to 1 GPa by means of the bending beam rheometer. WARNING The use of this European Standard may involve hazardous materials, operations and equipment. This European Standard does not purport to address all of the safety problems associated with its u
22、se. It is the responsibility of the user of this European Standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. 2 Normative references The following referenced documents are indispensable for the application of this E
23、uropean Standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 58, Bitumen and bituminous binders Sampling bituminous binders EN 12594, Bitumen and bituminous binders Preparation of
24、test samples 3 Terms and definitions For the purposes of this European Standard, the following terms and definitions apply. 3.1 flexural creep stiffness S (t) ratio obtained by dividing the bending stress by the bending strain; the strain will increase with the loading time and therefore the flexura
25、l creep stiffness will also be a function of time 3.2 m-value the absolute value of the slope of the curve of the logarithm of the stiffness versus the logarithm of time 3.3 contact load Pcload required to maintain positive contact between the test specimen, supports and the loading shaft NOTE The c
26、ontact load of 25 mN to 45 mN is used in this method. 3.4 test load Ptload used to determine the stiffness of the bituminous binder being tested NOTE The test load of 930 mN to 1030 mN is used in this method. Licensed Copy: Wang Bin, na, Tue Apr 18 02:38:08 BST 2006, Uncontrolled Copy, (c) BSIEN 147
27、71:2005 (E) 5 4 Principle The bending beam rheometer is used to measure the mid-point deflection, in three point bending, of a beam of bituminous binder. A constant load is applied to the mid-point of the test specimen for a defined loading time and the deflection is measured as a function of time.
28、A low temperature liquid bath is used to control the temperature. The stiffness of the test specimen for the specific loading times is calculated from the bending stress and strain. 5 Apparatus 5.1 Bending Beam Rheometer (BBR), consisting of a loading frame with test specimen supports, a controlled
29、temperature liquid bath and a data acquisition system. 5.1.1 The loading frame consists of a set of sample supports, a blunt-nosed shaft to apply the load to the mid-point of the test specimen, a load cell mounted in line with the loading shaft, a means for zeroing the load applied to the specimen,
30、a means for applying a constant load to the test specimen and a deflection measuring transducer attached to the loading shaft. A schematic picture of the device is shown in Figure 1. 5.1.1.1 The loading system shall be capable of applying a contact load of 25 mN to 45 mN to the test specimen and mai
31、ntaining a test load of 930 mN to 1030 mN within 10 mN. The rise time from the contact load to the test load shall be less than 0,5 s. Details of the loading pattern are shown in Figure 2. 5.1.1.2 The loading shaft shall be continuous and in line with the load cell and deflection measuring transduce
32、r with a spherically-shaped end 6,3 mm 0,3 mm in radius. 5.1.1.3 The load cell shall have a minimum capacity of no less than 2,0 N and a resolution of at least 2,5 mN. 5.1.1.4 The LVD-transducer, or other suitable device to measure the deflection of the test specimen shall have a linear range of at
33、least 6 mm, and be capable of resolving linear movement of 2,5 m. 5.1.1.5 The sample supports, shall consist of two non-corrosive metal supports with a 3,0 mm 0,3 mm contact radius and spaced 101 mm to 103 mm apart. The spacing of the supports shall be measured to0,3 mm, see Figure 3. 5.1.2 A temper
34、ature measurement device, as a calibrated temperature transducer shall be capable of measuring the temperature with the accuracy of 0,1 C over the range of 36 C to 0 C. The measuring head shall be mounted within 50 mm of the mid-point of the test specimen. 5.1.3 A liquid bath capable of maintaining
35、the desired test temperature near the test sample within 0,2 C during isothermal conditioning and during test procedure in the range of 36 C to 0 C. Bath liquid shall not affect the properties of the bituminous binder being tested. The density of the liquid shall not exceed 1050 kg/m3at the test tem
36、perature. NOTE 95 % (volume fraction) ethanol has been found to be suitable as a bath liquid. 5.1.3.1 A bath agitator shall be used for maintaining the required temperature homogeneity with agitation intensity such that the fluid currents do not disturb the testing process. 5.1.3.2 A circulating bat
37、h, an optional separate bath unit, cools the test bath liquid. 5.1.4 A data acquisition and control system resolves loads to at least 2,5 mN, test specimen deflection to at least 2,5 m, and bath liquid temperature to the nearest 0,1 C. The software shall control the measuring system and record time,
38、 load deflection and temperature during the test. All the load and deflection readings shall be an average of at least five points within 0,2 s of the reporting time. Licensed Copy: Wang Bin, na, Tue Apr 18 02:38:08 BST 2006, Uncontrolled Copy, (c) BSIEN 14771:2005 (E) 6 5.2 Test specimen moulds, wi
39、th the interior dimensions 6,4 mm 0,1 mm wide, 12,7 mm 0,1 mm deep and 127 mm 5 mm long fabricated from a suitable metal as shown in Figure 4. The thickness of the two end pieces used for each mould shall not vary from each other in thickness by more than 0,1 mm. NOTE Small errors in thickness of th
40、e test specimen can have a large effect on the calculated modulus because the calculated modulus is a function of the thickness raised to the third power. 6 Preparation of test samples 6.1 General The laboratory sample shall be taken in accordance with EN 58 and prepared in accordance with EN 12594.
41、 6.2 Preparation of moulds A very thin layer of petroleum-based grease is spread on the interior faces of the dry and clean metal mould sections. Press the plastic strips against the metal faces to force out any air bubbles. Cover the inside faces of the two end pieces with a thin film of demoulding
42、 agent to prevent bituminous binder from sticking to the metal end pieces. Assemble the mould as shown in Figure 4 using O-rings to hold the pieces of the mould together. Ensure plastic sheeting fits so that no raised edges occur on the cast beam. NOTE 1 Plastic sheeting 0,08 mm to 0,15 mm thick sho
43、uld be used. Transparency film sold for use with laser printer has been found suitable for this purpose. NOTE 2 Polyvinyl alcohol and glycerol are found to be suitable as demoulding agents. It is recommended to avoid silicone-based demoulding agents that may affect the binder stiffness. 6.3 Preparat
44、ion of test specimen Hot binder is poured into the metal mould that is at room temperature. Slightly overfill the mould. Pour the binder continuously toward the other end in a single pass. Let the filled mould cool in the ambient temperature for 45 min to 60 min. After cooling to room temperature tr
45、im the exposed face of the cooled specimen flush with the top of the mould using a hot knife or a heated spatula. Store all the test specimens in their moulds at the room temperature prior to testing. Testing shall be completed within 4 h after specimens are poured. NOTE 1 If the test is done at sev
46、eral temperatures then it may be practical to have longer time between pouring and testing, this may effect on the precision of the test. Just prior to demoulding, cool the mould containing the test specimen in a cold chamber or liquid bath for no longer than 5 min to stiffen the test specimen so th
47、at it can be readily demoulded without distortion. In no case shall the sample be exposed to a demoulding temperature less than the test temperature. At least two specimens per test temperature shall be tested. NOTE 2 Excessive cooling may cause unwanted hardening of the binder and affect the test r
48、esult. NOTE 3 During demoulding, the specimen should be handled with care to prevent distortion. A warped test specimen may affect the measured values. Licensed Copy: Wang Bin, na, Tue Apr 18 02:38:08 BST 2006, Uncontrolled Copy, (c) BSIEN 14771:2005 (E) 7 7 Procedure 7.1 Measurement Clean the suppo
49、rts, loading head and bath liquid of any dust and coatings as necessary. Check the adjustment of contact load and test load prior to testing each set of test specimens. Refer to the operating instructions of the apparatus for checking and calibration. Select the first test temperature according to the expected stiffness level. Set the temperature control device to the desired test temperature and allow the apparatus to equilibrate. The bath liquid shall be at the test temperature 0,2 C. After demoulding immediately place the test sp
