1、STDSBSI BS EN 932-L-ENGL 1797 m Lb2YbbS Ob33817 215 m BRITISH STANDARD Tests for general properties of aggregates Part 1. Methods for sampling The European Standard EN 932-1 : 1996 has the status of a British Standard ICs 91.100.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT L
2、AW BS EN 932-1 : 1997 BS EN 932-1 : 1997 Amd. No. Date Committees responsible for this British Standard Text affected This British Standard, 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 c
3、omes into effect on 15 May 1997 Q BSI 1997 The foliowing BSI references relate to the work on this standard Committee reference BI502 Draft for comment 92/19731 DC ISBN O 680 26804 7 The preparation of this British Standard was entrusted to Technical Committee B/502, Aggregates, upon which the follo
4、wing bodies were represented: Association of Consuiting Engineers Association of Lightweight Aggregate Manufacturers British Aggregate Constsuction Materials Indwtries British Cement Association British Iron and Steel Producers Association British Precast Concrete Federation Ltd. British Ready Mixed
5、 Concrete Association Department of the Environment Department of the Environment (Building Research Establishment) Department of kmsport (Highways Agency) Electricity Association Institute of Concrete Technology Institution of Civil Engineers Institution of Strucm Engineers Sand and Gravel Associat
6、ion Limited Society of Chemical Industry The following bodies were also represented in the drafting of the standad, through subcommittees and panels: British Civil Engineering Test Equipment Manfacturers Association County Surveyors Society Department of Thde and Indusry (National Measurement Accred
7、itation Service) STD-BSI BS EN 932-1-ENGL 1777 W lb24bb7 Ob33822 BOT BS EN 932-1 : 1997 O e Contents Committees responsible Inside hnt cover National foreword u Foreword 2 Text Of EN 932-1 3 O BSI 1997 i STD*BSI BS EN 932-1-ENGL 1977 Lb24bb7 Ob33823 74b BS EN 932-1 : 1997 National foreword This Brit
8、ish Standard has been prepared by Technical Committee B/502. It is the English language version of EN 932-1 : 1996 Testsfor general properties of aggregates -Part i: Mewd-s for sampling published by the European Committee for Standardization (CEN). It forms part of a group of European standards deal
9、ing with test methods for aggregates which are being developed by CENITC: 154 to verify requirements which will be specified in European product standards for aggregates for various end uses. It is intention that this standard will be included in a package of European Standards to be declared by CEN
10、m 154 and when all the associated European test methods for aggregates are available, this Part of this European Standard will supersede BS 812 : Past 102 : 1989 Testing aggregates Part 102. Methods for sampling. Compliance with a British Standard does not of itself confer immunity from legal obliga
11、tions. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages 2 to 18, an inside back cover and a back cover. ii O BSI 1997 STD.BS1 BS EN 732-1-ENGL 1777 Lb2Libb7 b33824 682 GuRopEAN mmm Nom EUROPENNE EUROP is the maximum grain size, i
12、n miilimetres; is the loose bulk density, in megagrams per cubic metre, determined as specified in prEN 1097-3. NOTE 2. A procedure that producers can use to check that they are taking numbers of sampling increments that are adequate for their products and processes is given in annex B. O BSI 1997 S
13、TD.BS1 BS EN 732-1-ENGL 1777 LbZqbb b33827 391 Page 4 EN 932-1 : 1996 6 Sampling plan A sampling plan shall be prepared, prior to sampling, talung into account the aggregate size, the nature and size of the batch, the local circumstances and the purposes of sampling. It shall include: - the type of
14、the aggregates; - the ahn of the sampling including a list of the properties to be tested; - the identification of the sampling points; - the approximate mass of sampling increments; - the number of sampluig increments; - the sampling apparatus to be used; - the methods of sampluig and sample reduct
15、ion with reference to the clauses of this European standard; - the marlung, packaging and dispatch of the samples. 7 Apparatus AU apparatus shall comply with the general requirements of prEN 932-5. NOTE 1. General advice for apparatus to be used in sampling and sample reduction is given in annex A.
16、In all cases the width w of the opening of apparatus used in sampling shall be not less than three times the upper aggregate size of the batch and in no case less than 10 mm. NOTE 2. The same applies to the dimensions indicated in the figures of annex A. Equipment to be used in sample reduction is a
17、lso given inannexk NOTE 3. in all cases, alternative designs may be used so long as the essential dimensions of width of opening and length are met and the devices can be used to fulfil the sampling methods described in clause 8 or the reduction methods described in clause 9. 8 Sampling procedures 8
18、.1 General Regulahons for safety and ergonomics shali be followed NOTE 1. The sampling methods wili inevitably involve the samplers working close to processing plant and moving vehicles. Those involved in the planning and execution of sampling should work closely with the operational management to e
19、nsure safe working practices. NOTE 2. Aggregates should preferably be sampled from a stationary conveyor belt or from the stream of materiai. Sampling increments should be taken at regular intervals throughout the period the batch is in motion. NOTE 3. When samphg from stockpiles as described in 8.8
20、 is canied out, it is difficult to satisfy the principle of taking sampling increments at random from ail parts of the batch, so that segregation can cause the sampling to produce biased results. Therefore, this method, wherever possible, should be avoided. Manual sampling with shovels or scoops etc
21、 shall not be applied to moving makrials. 8.2 Sampling from stationary conveyor belts NOTE 1. Sampling should oniy be started after a preliminary run to ensure that possible irregularities in the pass do not cause a false sample to be taken. All samphg increments shall be taken at the same samphg po
22、int. The materiai shall be taken across the complete Cros section of the belt in every sampling increment. NOTE 2. The sampling frame (see A.3) should be used to separate the material that is to be taken as the sampling increment at the sampling point As an alternative to the use of the samphng fram
23、e a shovel or a flat piece of metal can be used to separate the sampling increment at both ends from the material remaining on the belt. This increment should have the length of about three times the width of the material stream on the belt or a minimum mass as calculated according to the equation g
24、iven in clause 5. 8.3 Sampling at belt and chute discharge points NOTE 1. Mechanical apparatus provides the most practical means of talung samples from belt and chute discharge points. Manual sampling should be avoided if possible, due to both errors and dangers involved. The period during which the
25、 sampling is to be done shall be divided into a number of equal intervais, and a sampling increment shail be taken in the middle of each interval. A sampling increment shall be taken by passing the sampling receptacle e.g. the sampling box (see A.4) through the discharge stream in a uniform movement
26、, making sure that the complete cross section of the stream of material is intercepted. NOTE 2. Where appropriate, sampling should only be started after a preliaq run to ensure that possible irregularities in the pass do not cause a false sample to be taken. NOTE 3. Samples can also be taken at the
27、discharge from a screen by the same method. 8.4 Sampling of pneumatically transported aggregates Samphg from the pneumatic transport in a plant shall be carried out in accordance with 8.3 and by means of sampling equipment installed by the producer. This sampiing equipment, mostly based on a by-pass
28、 principle, shall be designed in such a way that the whole stream of the aggregate can be interrupted to form an increment through the bypass. 8.5 Sampling of packed aggregates When aggregate is packed in bags, drums or other smal containem, a bulk sample shd be obtained by selecting a number of pac
29、ks at random. NOTE. A whole pack can be taken as a sampling increment, or the sampling spear (see A.6) used to take one sampling increment from each of the selected packs, or each of the selected packs can be reduced by one of the procedures described in clause 9. O BSI 1997 Whenever possible random
30、 selection of packs shall be achieved by selecting packs at random times as they pass a chosen sampling point during loading or unloadmg, or by numbering ail the packs and using random numbers (see mexes D and E). 8.6 Sampling of material in bucket conveyors, bucket loaders, or grabs Each sampling i
31、ncrement shall consist of the entire contents of a grab or bucket. NOTE. When this gives too large a sampling increment, it should be reduced by one of the methods described in clause 9, or discharged to form a small stockpile and sampled accordmg to 8.8. 8.7 Sampling from a silo Sampling at an outl
32、et shall be canied out in accordance with 8.3. The silo shall be opened sufficiently to ensure a uniform materiai flow without segregation; this requires an aperture at least three times the diameter of the maximum grain diameter. For aggregates with a lower size above 32 mm an aperture of at least
33、200 mm is required. 8.8 Sampling from stockpiles Sampling increments of approximately equal size shail be taken from different points at different heights or depths, distributed over the complete stockpile (see figure i), The location and number of sampling increments shall take into account the way
34、 in which the stockpile was built, its shape and the possibility of segregation within the stockpile. A sampling increment shall be taken using a scoop (see A.l), a shovel (see A.2) or a grab (A.7) from the deepest point of each hole. I I Figure 1. Sampling from flat stockpiles NOTE. Conical stockpi
35、les present special problems. Further guidance on sampling from such stockpiles is given in annex C. 8.9 Sampling from railway wagons, lorries and Sampling of singlesized aggregates and of free flowing fine aggregate from lorries may be carried out as described in 8.8. Sampling of fine aggregate fro
36、m lorries may also be carried out by using the sampiing tube (see A.6); each sampling increment shall be taken by inserting the tube vertically down through the full depth of the aggregate. ships Page 5 EN 932-1 : 1996 In other situations, proper sampling from railway wagons, lorries or ships may no
37、t be possible. Sampling shall therefore be carried out wherever possible during loading or discharge according to 8.2, 8.3 or 8.6. Only when this is not possible, the aggregate shall be discharged to form a stockpile and sampled according to 8.8. 9 Sample reduction 9.1 General The procedure describe
38、d in 9.2 shall preferably be used for the preparation of laboratory samples from buk samples of aggregates. The procedures described in 9.4, 9.6 and 9.6 may be used when the other methods are not suitable or the devices are not available. All the procedures may also be used in combination, for examp
39、le by using quartering for the first few reduction stages followed by riffling. NOTE. For all-in aggregates with an upper aggrkgate size of more than 63 mm, it may be suitable to remove aggregates coarser than 63 mm and treat them separately. If nece-, the bulk sample shall be brought to a condition
40、 in which it is free-flowing but not so dry that fines will be lost or accretion occurs. For rnixjng, and other operations that require a working surface, use a clean, flat, hard surface such as a sampling tray (see A.9) or a glass plate (for fillers). If a shovel is required it shall be in accordan
41、ce with clause 7. If a rotatory sample divider is available it is preferred for sample reduction. 9.2 Reduction of a bulk sample using a riffle box Put the buk sample inb one of the riffe box (see A.lO) receptacles and place the other two in position. Pour the aggregate from the long side of the rec
42、eptacle down the centre line of the riffle box. Discard the aggregate that f b) the laboratory sample identification mark(s); c) the date and place of sampling d) the gradhg type and size of the batch e) sampling point or identification of the batch sampled f) a reference to the sampling plan prepar
43、ed according to clause S; g) the name of sampler(s). NOTE. Depending on the circumstances other information can be relevant. Figure 3 shows an example of a comprehensive sampling report. O BSI 1997 * * m STD-BSI BS EN 732-1-ENGL 1777 lb24bb9 Ob33830 78b = Page 7 EN 932-1 : 1996 Qt w a 3 m a Y td M M
44、 M td k O fi O a 2 P PH Li 7 O BSI 1997 STD-BSI BS EN 732-L-ENGL i777 1b2ibbS Ob33831 812 Page 8 EN 932-1 : 1996 O Annex A (informative) Examples of equipment for sampling and sample reduction A.l Scoop (see figures Al and A.2) Requirements for dimensions are given in clause 7. Figure A.l Example of
45、 a sampling scoop with a rectangular cross-sectior Figure A.2 Example of a sampling scoop with a circular cross-section A.2 Shovel (see figure A.3) Requirements for dimensions are given in clause 7. A.3 Sampling frame (see figure A.4) The sides of the sampiing frame are parallel and shaped to fit th
46、e conveyor belt and their length is approximately the breadth of the belt. The sides of the sampling frame are high enough to prevent particles spilling over the top. The opening w is at least three times the maximum particle size. A.4 Sampling box (see figureA.5) The sides of the sampling box are v
47、ertical and opposite sides are parallel. The edges around the top of the sampling box are rounded. The capacity of the sampiing box is such that it is not more than half- Wed by a samphg increment. The width w of the opening complies with clause 7. The length I of the opening is large enough to allo
48、w the complete stream of materiai to be intercepted. The depth of the sampling box is such that no particles are lost by jumping out of the box. AO Sampling tube (see figure k6) The sampling tube consists of two tubes, one inside the other. Both tubes have openings down their operational lengths, so
49、 that by turning one tube relative to the other, aggregate is allowed to enter the sampling tube and is then trapped in it. The length 1 of the sampling tube is between loo0 mm and 2000 mm. The width w of the openings of the inner and outer tubes conforms to clause 7. The wall thickness of the tubes are such that they will withstand norma use without deformation O BSI 1997 STD.BS1 BS EN 732-1-ENGL 1977 Lb24bb7 b33832 757 H Page 9 EN 932-1 : 1996 A-A n Figure A.3 Examples of a shovel Figure A.4 Example of a sampling frame O BSI 1997 STD.BSI BS EN 932-L-ENGL 1797 H Lb24b
