1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 933-7:1998 The Euro
2、pean Standard EN 933-7:1998 has the status of a British Standard ICS 91.100.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Tests for geometrical properties of aggregates Part 7: Determination of shell content Percentage of shells in coarse aggregatesThis British Standard,
3、having been prepared under the direction of the Sector Board for Building and Civil Engineering, was published under the authority of the Standards Board and comes into effect on 15 July 1998 BSI 1998 ISBN 0 580 29780 2 BS EN 933-7:1998 Amendments issued since publication Amd. No. Date Text affected
4、 National foreword This British Standard is the English language version of EN 933-7:1998. It supersedes BS 812-106:1985 which, it is intended, will be withdrawn on 1999-12-01 if all the European Standards included in the package are available. The UK participation in its preparation was entrusted b
5、y Technical Committee B/502, Aggregates, to Subcommittee B/502/6, Test methods, which has the responsibility to: aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monit
6、or related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this do
7、cument may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of
8、 British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 5 and a back cover.CEN European
9、 Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1998 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 933-7:1998 E EUROPEAN
10、 STANDARD EN 933-7 NORME EUROPE ENNE EUROPA ISCHE NORM March 1998 ICS 91.100.20 Descriptors: Aggregates, tests, geometrical characteristics, determination, percentage, gravel English version Tests for geometrical properties of aggregates Part 7: Determination of shell content Percentage of shells in
11、 coarse aggregates Essais pour de terminer les proprie te sg e ome triques des granulats Partie 7: De termination de la teneur en e le ments coquilliers Pourcentage des coquilles dans les gravillons Pru fverfahren fu r geometrische Eigenschaften von Gesteinko rnungen Teil 7: Bestimmung des Muschelsc
12、halengehaltes Prozentsatz von Muschelschalen in groben Gesteinko rnungen This European Standard was approved by CEN on 15 February 1998. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national
13、 standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any ot
14、her language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany,
15、Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.Page 2 EN 933-7:1998 BSI 1998 Foreword This European Standard has been prepared by Technical Committee CEN/TC 154, Aggregates, the secretariat of which is held by BSI. This stand
16、ard forms part of a series of tests for geometrical properties of aggregates. Test methods for other properties of aggregates will be covered by parts of the following European Standards: EN 932, Tests for general properties of aggregates. EN 1097, Tests for mechanical and physical properties of agg
17、regates. EN 1367, Tests for thermal and weathering properties of aggregates. EN 1744, Tests for chemical properties of aggregates. A European Standard Tests for filler aggregate used in bituminous mixtures is in the course of preparation. The other parts of EN 933 will be: Part 1: Determination of p
18、article size distribution Sieving method. Part 2: Determination of particle size distribution Test sieves, nominal size of apertures. Part 3: Determination of particle shape Flakiness index. Part 4: Determination of particle shape Shape index. Part 5: Assessment of surface characteristics Percentage
19、 of crushed and broken surfaces in coarse aggregates. Part 6: Assessment of surface characteristics Flow ocoefficient of coarse aggregates. Part 8: Assessment of fines Sand equivalent test. Part 9: Assessment of fines Methylene blue test. Part 10: Assessment of fines Grading of fillers (air jet siev
20、ing). This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 1998, and conflicting national standards shall be withdrawn at the latest by December 1999. According to the CEN/CENELEC Internal Re
21、gulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and th
22、e United Kingdom. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Definitions 3 4 Principle 3 5 Apparatus 3 6 Preparation of test portion 3 7 Procedure 4 8 Calculation and expression of results 4 9 Test report 5 Annex A (informative) Example of a test data sheet 5Page 3 EN 933-7:1998 B
23、SI 1998 1 Scope This European Standard specifies a method for the determination of shell content of coarse aggregates. It applies to gravel or mixed aggregate containing gravel. The test method specified in this part of this European Standard is applicable to particle size fractions d i /D i where D
24、 i # 63 mm and d i $ 4 mm. NOTE For aggregate sizes with D 63 mm and/or d4mmt h e test may be carried out on particle size fractions d i /D i where D i # 63 mm and d i $ 4 mm. 2 Normative references This European Standard incorporates by dated or by undated reference, provisions from other publicati
25、ons. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. F
26、or undated references, the latest edition of the publication referred to applies. prEN 932-2, Tests for general properties of aggregates Part 2: Methods for reducing laboratory samples. prEN 932-5, Tests for general properties of aggregates Part 5: Common equipment and calibration. EN 933-1, Tests f
27、or geometrical properties of aggregates Part 1: Determination of particle size distribution Sieving method. EN 933-2, Tests for geometrical properties of aggregates Part 2: Determination of particle size distribution Test sieves, nominal size of apertures. 3 Definitions For the purposes of this Euro
28、pean Standard the following definitions apply. 3.1 aggregate size a designation of aggregate in terms of lower (d) and upper (D) sieve sizes NOTE This designation accepts the presence of some particles which will be retained on the upper sieve (oversize) and some which will pass the lower sieve (und
29、ersize). 3.2 particle size fraction d i /D i fraction of an aggregate passing the larger (D i ) of two sieves and retained on the smaller (d i ) NOTE The lower limit may be zero. 3.3 test portion the sample used as a whole in a single test 3.4 constant mass successive weighings after drying at least
30、 1 h apart not differing by more than 0,1 % NOTE In many cases constant mass can be achieved after a test portion has been dried for a pre-determined period in a specified oven (see 5.3) at (110 5)8C. Test laboratories may determine the time required to achieve constant mass for specific types and s
31、izes of sample dependent upon the drying capacity of the oven used. 3.5 shell the hard outer casing of a testaceous animal 4 Principle The test consists of sorting by hand shells and shell fragments from a test portion of coarse aggregate. The shell content is determined as the proportion of the mas
32、s of shells and shell fragments to the mass of the test portion. The shell content, SC, is expressed as a percentage. 5 Apparatus Unless otherwise stated, all apparatus shall conform to the general requirements of prEN 932-5. 5.1 Test sieves, of nominal size of apertures in accordance with EN 933-2.
33、 5.2 Tightly fitting pan and lid, for the sieves. 5.3 Ventilated oven, thermostatically controlled to maintain a temperature of (110 5)8C, or equipment for drying the aggregate which does not cause any particle size breakdown. 5.4 Balances or scale, of suitable capacity, readable to 0,1 % of the mas
34、s to be weighed. 5.5 Trays. 5.6 Brushes. 5.7 Sieving machine, optional. 6 Preparation of test portion The sample shall be reduced in accordance with the requirements of prEN 932-2. Dry the sample at (110 5)8C to constant mass. Weigh and record the mass as M 0 . Sieve on appropriate test sieves, agit
35、ating with sufficient vigour to ensure complete separation of particles greater than 4 mm. Discard the particles retained on the 63 mm test sieve and those passing the 4 mm test sieve.Page 4 EN 933-7:1998 BSI 1998 If necessary further reduce the sample in accordance with prEN 932-2 to produce a test
36、 portion. Record the mass of the test portion as M 1 . The mass of the test portion shall be as specified in Table 1. Table 1 Mass of test portions Upper aggregate size D Test portion mass (minimum) mm kg 63 45 32 6 16 1 8 0,1 NOTE For other aggregate sizes D, appropriate test portion masses may be
37、interpolated from those given in Table 1. Sample reduction shall yield a test portion of mass larger than the minimum but not of an exact predetermined value. Carry out the test on each particle size fraction d i /D i where D i # 2 d i . Samples for which D 2dshall first be separated into particle s
38、ize fractions d i /D i where D i # 2 d i . 7 Procedure 7.1 Test portions where D# 2 d Spread the particles of the test portion on a flat surface and separate out the shells and shell fragments by hand. Weigh the shells and shell fragments and record their mass M 2 . 7.2 Test portion where D 2d Separ
39、ate the test portion into particle size fractions d i /D i where D i # 2 d i by sieving in accordance with EN 933-1. Record the mass of each particle size fraction as M i and calculate and record the percentage by mass of each particle size fraction d i /D i to the test portion mass M 1 as V i . Dis
40、card any size fraction d i /D i which comprises less than 10 % of M 1 . NOTE 1 Any remaining size fraction d i /D i which contains less than 100 particles should, if required, be recorded in the test report. NOTE 2 Size fractions d i /D i which contain an excessive number of particles can be further
41、 reduced in accordance with prEN 932-2. NOTE 3 Size fractions can be further reduced if they consist of significantly more than 200 particles. Record the mass of particles to be tested in each remaining particle size fraction d i /D i as M 1i and sort them as specified in 7.1. Record the mass of she
42、ll and shell fragments in each of these size fractions d i /D i as M 2i . 8 Calculation and expression of results 8.1 Test portions where D# 2 d Calculate the shell content SC in accordance with the following equation: SC =( M 2 / M 1 )3100 where: M 1 is the mass of the test portion, in grams; M 2 i
43、s the mass of the shells and shell fragments, in grams. Record the value of SC to the nearest whole number. 8.2 Test portions where D 2d 8.2.1 Size fractions not reduced If no size fractions have been reduced calculate the shell content in accordance with the following equation: SC = 3 100 M 2i M 1i
44、 where: M 1i is the sum of the masses in the size fractions tested, in grams. M 2i is the sum of the masses of shells and shell fragments in each of the size fractions tested, in grams. Record the value of SC to the nearest whole number. 8.2.2 Reduced size fractions If any size fractions have been r
45、educed calculate the percentages by mass of shells and shell fragments in each particle size fraction and record as SC i . Calculate the weighted mean percentage value of the shells and shell fragments in accordance with the following equation: SC = (V i SC i ) V i where: V i is the percentage by ma
46、ss of particle size fraction i in the sample tested; SC i is the percentage by mass of shells and shell fragments in particle size fraction i. Record the weighted mean percentage of shells and shell fragments to the nearest whole number.Page 5 EN 933-7:1998 BSI 1998 9 Test report 9.1 Required data T
47、he test report shall include the following information: a) reference to this European Standard; b) identification of the sample; c) identification of the laboratory; d) sample reception date; e) shell content SC, to the nearest whole number; f) where applicable, the weighted mean percentage. 9.2 Opt
48、ional data The test report may include the information: a) name and location of the sample source; b) description of the material and of the sample reduction procedure; c) visual description of shells (e.g., hollow or flat); d) mass of sample M 0 ; e) mass of test portion M 1 ; f) mass of shells and
49、 fragments M 2 ; g) any size fraction consisting of less than 100 particles; h) sampling certificate, if available; i) date of test. Annex A (informative) Example of a test data sheet EN 933-7 Laboratory: Identification of the sample: Date: Operator: M 0 =g Particle size fraction d/D i where D i # 2 d i Mass M 1 Mass M 2 Shell content SC =( M 2 / M 1 )3100 (to the nearest whole number) mm g g % NOTE When a particle size fraction d i /D i has been reduced, an appropriate test d
