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1、BRITISH STANDARD BS 1881-103: 1993 Testing concrete Part 103: Method for determination of compacting factor Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 1881-103:1993 This British Standard, having been prepared under the direction of T
2、echnical Committee B/517, was published under the authority of the Standards Board and comes into effect on 15 December 1993 BSI 12-1998 First published May 1983 Second edition December 1993 The following BSI references relate to the work on this standard: Committee reference B/517/1 Special announc
3、ement in BSI News February 1993 ISBN 0 580 22262 4 Committees responsible for this British Standard The preparation of this British Standard was entrusted by Technical Committee B/517, Concrete, to Subcommittee B/517/1, Concrete production and testing, upon which the following bodies were represente
4、d: Association of Lightweight Aggregate Manufacturers Association of Metropolitan Authorities British Aggregate Construction Materials Industries British Cement Association British Civil Engineering Test Equipment Manufacturers Association British Precast Concrete Federation British Ready Mixed Conc
5、rete Association Building Emloyers Confederation Cement Admixtures Association Cementitious Slag Makers Association Concrete Society County Surveyors Society Department of the Environment (Building Research Establishment) Department of the Environment (Property Services Agency) Department of Transpo
6、rt Department of Transport (Transport Research Laboratory) Electricity Association Federation of Civil Engineering Contractors Institute of Concrete Technology Institution of Civil Engineers Institution of Structural Engineers Institution of Water and Environmental Management National House-Building
7、 Council Quality Ash Association Sand and Gravel Association Society of Chemical Industry Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 1881-103:1993 BSI 12-1998i Contents Page Co
8、mmittees responsibleInside front cover Forewordii 1Scope1 2References1 3Definitions1 4Apparatus1 5Sampling1 6Preparing the sample2 7Gravimetric procedure2 8Expression of results4 9Report4 Annex A (normative) Volumetric procedure6 Figure 1 Compacting factor apparatus3 Table 1 Essential dimensions of
9、the compacting factor apparatus2 Table 2 Precision data for compacting factor measurements4 List of referencesInside back cover Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 1881-103:1993 ii BSI 12-1998 Foreword This Part of BS 1881 has
10、 been prepared under the direction of Technical Committee B/517, Concrete. It is a new edition that incorporates the minor changes to equipment made in 1989, the data on the precision of the method when using the conventional (gravimetric) procedure, added by amendment in 1992, and a new annex on th
11、e volumetric procedure. This edition does not represent a full revision as test methods for concrete are currently in preparation by CEN/TC 104 “Concrete Performance, production, placing and compliance criteria” and the UK is fully involved in this work. The resulting European Standards will be impl
12、emented as revisions of the corresponding Parts of BS 1881. This new edition of BS 1881-103 supersedes BS 1881-103:1983 and DD 90:1983, which are withdrawn. The new annex A describes the alternative (volumetric) procedure for determining the compacting factor. This procedure was originally published
13、 in DD 90:1983. By this procedure the compacting factor is determined from the reduction in volume that occurs when a defined volume of partially compacted concrete is fully compacted. This has the advantage of not requiring the use of scales or a balance and can be carried out in less time than the
14、 gravimetric method. The volumetric procedure is similar to that described in ISO 4111. Four methods of determining the workability of concrete are given in Parts 102 to 105 of BS 1881, these being the slump, compacting factor, Vebe time and flow methods. The methods are appropriate to concrete mixe
15、s of different workability as follows: There are no unique relationships between the values yielded by the four methods. Relationships depend upon such factors as the shape of the aggregate, the sand fraction and the presence of entrained air. A British Standard does not purport to include all the n
16、ecessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. WorkabilityMethod Very lowVebe time LowVebe time, compacting factor MediumCompacting factor, slum
17、p HighCompacting factor, slump, flow Very highFlow Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 6, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This wi
18、ll be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 1881-103:1993 BSI 12-19981 1 Scope This Part of BS 1881 describes the method for determining the compacting factor of concre
19、te of low, medium and high workability. The method applies to plain and air-entrained concrete, made with lightweight, normal weight or heavy aggregates having a nominal maximum size of 40 mm or less but not to aerated concrete, no-fines concrete and concrete which cannot be compacted by vibration a
20、lone. The measurement of compacting factor is not suitable for determining the workability of concrete when the value obtained lies outside the range 0.70 to 0.98. The method can be carried out either by using the conventional (gravimetric) procedure or by using the alternative (volumetric) procedur
21、e described in annex A. 2 References 2.1 Normative references This Part of BS 1881 incorporates, by reference, provisions from specific editions of other publications. These normative references are cited at the appropriate points in the text and the publications are listed on the inside back cover.
22、 Subsequent amendments to, or revisions of, any of these publications apply to this Part of BS 1881 only when incorporated in it by updating or revision. 2.2 Informative references This Part of BS 1881 refers to other publications that provide information or guidance. Editions of these publications
23、current at the time of issue of this standard are listed on the inside back cover, but reference should be made to the latest editions. 3 Definitions For the purposes of this Part of BS 1881 the definitions given in BS 5328-1:1991 and BS 1881-101:1983 apply. 4 Apparatus 4.1 Sampling tray, minimum di
24、mensions 900 mm 900 mm 50 mm deep, of rigid construction and made from a non-absorbent material not readily attacked by cement paste. 4.2 Square mouthed shovel, size 2 in accordance with BS 3388:1973. 4.3 Scales or balance, capable of weighing up to 25 kg and accurate to within 10 g. The balance sha
25、ll be calibrated on initial commissioning, and at least annually thereafter, using weights of which the accuracy can be traced to the national standard of mass. The balance shall be checked after relocation or disturbance. A certificate stating the accuracy of the balance shall be obtained from the
26、organization carrying out the check. 4.4 Compacting factor apparatus, consisting of two conical hoppers mounted above a cylinder; its essential dimensions are shown in Table 1 and Figure 1. The hopper and cylinder shall be of rigid construction and made of metal not readily attacked by cement paste.
27、 The interior surfaces shall be smooth and free from projections such as protruding rivets and shall be free from dents. The rim of the cylinder shall be machined to a plane surface at right angles to its axis. The lower ends of the hoppers shall have tightly fitting hinged trap doors made of rigid
28、non-corrodible metal plate, 3 mm thick. The doors shall have quick release catches which allow them to swing rapidly to a position at which they are caught by retaining catches which hold them clear of concrete falling through the bottom of the hopper. The frame in which the hoppers and cylinder are
29、 mounted shall be of rigid construction and shall firmly locate them in the relative positions indicated in Table 1. The cylinder shall be easily detachable from the frame. 4.5 Steel floats. Two plasterers steel floats. 4.6 Scoop, as described in 3.1 of BS 1881-101:1983. 4.7 Tamping rod, made out of
30、 straight iron or steel bar of circular cross section, (16 1) mm diameter and (600 5) mm long, with both ends hemispherical. 4.8 Compacting bar or vibrator. Compacting bar made from iron or steel, weighing (1.8 1.0) kg, at least 380 mm long and having a ramming face (25.0 0.5) mm square; or a vibrat
31、ing hammer or table suitable for compacting the concrete in accordance with 7.2 or 7.3. 5 Sampling Obtain the sample of fresh concrete by the procedure given in BS 1881-101:1983 or BS 1881-125:1986. Commence the determination of compacting factor as soon as possible after sampling. Licensed Copy: sh
32、effieldun sheffieldun, na, Fri Nov 24 08:28:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 1881-103:1993 2 BSI 12-1998 Table 1 Essential dimensions of the compacting factor apparatus 6 Preparing the sample Empty the sample from the container(s) onto the sampling tray (4.1). Ensure that no more tha
33、n a light covering of slurry is left adhering to the container(s). Thoroughly mix the sample by shovelling it to form a cone on the sampling tray and turning this over with the shovel (4.2) to form a new cone, the operation being carried out three times. When forming the cones, deposit each shovelfu
34、l of the material on the apex of the cone so that the portions which slide down the sides are distributed as evenly as possible and so that the centre of the cone is not displaced. Flatten the third cone by repeated vertical insertion of the shovel across the apex of the cone, lifting the shovel cle
35、ar of the concrete after each insertion. CAUTION. When cement is mixed with water, alkali is released. Take precautions to avoid dry cement entering the eyes, mouth and nose when mixing concrete. Prevent skin contact with wet cement or concrete by wearing suitable protective clothing. If cement or c
36、oncrete enters the eye, immediately wash it out thoroughly with clean water and seek medical treatment without delay. Wash wet concrete off the skin immediately. Determine the compacting factor in accordance with clauses 7 and 8, or in accordance with annex A. 7 Gravimetric procedure 7.1 Procedure 7
37、.1.1 Using the scales or balance (4.3), weigh the empty cylinder (4.4) and record its mass to the nearest 10 g. 7.1.2 Ensure that the internal surfaces of the hoppers (4.4) and cylinder are smooth, clean and damp but free from superfluous moisture. Place the frame (4.4) in a position free from vibra
38、tion or shock in such a manner that it is stable with the axes of the hoppers and the cylinder all lying on the same vertical line. Close the two trap doors and place the two floats (4.5) on the cylinder so as to cover its top. DetailDimension mm Preferred apparatusAlternative apparatusa Upper hoppe
39、r A: Top internal diameter, D260 2254 2 Bottom internal diameter, E130 2127 2 Internal height, F280 2279 2 Lower hopper B: Top internal diameter, G240 2229 2 Bottom internal diameter, H130 2127 2 Internal height, J240 2229 2 Distance, K, between bottom of upper hopper A and top of lower hopper B 200
40、 5203 5 Distance, L, between bottom of lower hopper B and top of cylinder C 200 5203 5 Cylinder C: Internal diameter, M150 1152 1 Internal height, N285 1305 1 Radius between wall and base, P20 a Owing to current availability, apparatus having the dimensions given in this column may be used until 31
41、January 1995. The column will then be deleted by amendment and the use of such apparatus will no longer comply with the standard. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 1881-103:1993 BSI 12-19983 7.1.3 Place the sample of concret
42、e gently in the upper hopper using the scoop (4.6) until the hopper is filled to the level of the rim. Open the upper trap door so that the concrete falls into the lower hopper. Immediately after the concrete has come to rest, remove the floats from the top of the cylinder, open the trap door of the
43、 lower hopper and allow the concrete to fall into the cylinder. 7.1.4 Certain mixes have a tendency to stick in one or both of the hoppers. If this occurs, help the concrete through by pushing the tamping rod (4.7) gently into the concrete from the top until the lower end emerges from the bottom of
44、the hopper.If this does not dislodge the concrete, raise the rod and repeat the process until the concrete falls through the hopper. Count the number of times the concrete is rodded as this provides a guide to the cohesiveness of the concrete. 7.1.5 Cut off the excess concrete remaining above the le
45、vel of the top of the cylinder by holding a float in each hand, with the plane of the blades horizontal, and moving them simultaneously one from each side across the top of the cylinder, at the same time keeping them pressed on the top edge of the cylinder. Wipe clean the outside of the cylinder. 7.
46、1.6 Within 150 s of placing the sample in the upper hopper (7.1.3), weigh the cylinder and its contents. By subtracting the mass of the empty cylinder, calculate and record the mass of the partially-compacted concrete to the nearest 10 g. 7.1.7 Empty the partially-compacted concrete from the cylinde
47、r and refill it with concrete from the same sample in such a way as to remove as much entrapped air as possible (without significantly reducing the amount of entrained air, if present) Figure 1 Compacting factor apparatus Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 24 08:28:19 GMT+00:00 2006
48、, Uncontrolled Copy, (c) BSI BS 1881-103:1993 4 BSI 12-1998 and to produce full compaction of the concrete with neither excessive segregation nor laitance. For this purpose, by means of the scoop, place the concrete in the cylinder in six layers approximately equal in depth and compact each layer by
49、 using either the compacting bar or the vibrator in the manner described in 7.2 or 7.3. After the top layer has been compacted, smooth it level with the top of the cylinder, using one of the plasterers floats, and wipe clean the outside of the cylinder. Weigh the cylinder and its contents to the nearest 10 g, and by subtracting the mass of the empty cylinder, calculate and record the mass of the fully-compacted concrete to the nearest 10 g. 7.2 Compacting with compacting bar When compacting each layer with t