1、DEUTSCHE NORM October 1998 Methods of test for masonry units Part 4: Determination of real and bulk density and of total and open porosity for natural stone masonry units English version of DIN EN 772-4 DIN - EN 772-4 ICs 91.1 00.20 Descriptors: Masonry units, natural stone, density, porosity, testi
2、ng. Prfverfahren fr Mauersteine - Teil 4: Bestimmung der Dichte und der Rohdichte sowie der Gesamtporosi- tt und der offenen Porositt von Mauersteinen aus Naturstein European Standard EN 772-4 : 1998 has the status of a DIN Standard. A comma is used as the decimal marker. National foreword This stan
3、dard has been prepared by CEN/TC 125. The responsible German body involved in its preparation was the Normenausschu Bauwesen (Building and Civil Engineering Standards Committee), Technical Committee Mauerwerksbau. EN comprises 8 pages. No pari of this standard may be reproduced without the prior per
4、mission of Ref. No. DIN EN 772-4 : 1998-1 V Deutsches Institut fur Normung e. V., Berlin. Luth Verlag GmbH, D-10772 Berlin, has the exclusive right of sale for German Standards (DIN-Normen). English price group 05 . Sales No. 1105 04.99 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 772-4 Augu
5、st 1998 ICs 91.1 00.20 Descriptors: Masonry units, natural stone, density, porosity, testing. English version Methods of test for masonry units Part 4: Determination of real and bulk density and of total and open porosity for natural stone masonry units Mthodes dessai des lments de maconnerie - Part
6、ie 4: Dtermination des masses volumiques relle et apparente et des porosits ouverte et totale des lments de maconnerie en pierre naturelle Prfverfahren fr Mauersteine -Teil 4: Bestimmung der Dichte und der Roh- dichte sowie der Gesamtporositt und der offenen Porositt von Mauer- steinen aus Naturstei
7、n This European Standard was approved by CEN on 1998-07-02. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical referen
8、ces concerning such national stand- ards may be obtained on application to the Central Secretariat or to any CEN member. The European Standards exist in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member int
9、o 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, the Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Por
10、tugal, Spain, Sweden, Switzerland, and the United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels O 1998. CEN - All rights of exploitation in any form and by any means reserved
11、worldwide for CEN national members. Ref. No. EN 772-4 : 1998 E Page 2 EN 772-4 : 1998 Contents Foreword 1 2 3 4 5 6 7 8 9 10 11 Scope Normative references Principle Symbols Materials Apparatus Preparation of the specimens Procedure Calcuiation and expression of results Evaluation of test results Tes
12、t report Page 3 3 3 3 3 4 4 4 5 5 7 7 Page 3 EN 772-4 : 1998 Foreword This European Standard has been prepared by Technical Committee CEN/TC 125 “Masonry”, the secretariat of which is held by BSL This European Standard shall be given the status of a national standard, either by publication of an ide
13、ntical text or by endorsement, at the latest by February 1999, and conflicting national standards shall be withdrawn at the latest by February 1999. According to the CENCENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European
14、Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands. Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. 1 Scope This European Standard specifies a method of determining the real density and the bulk
15、 density and the open and total porosity of natural stone masonry units. 2 Normative references This European Standard incorporates by dated or undated reference, provision from other publications. These normative references are cited at the appropriate places in the text and the publications are li
16、sted 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. For undated references, the latest edition of the publication referred to applies. pr EN 77 1-6 Specificatio
17、n for masonry units - Pari 6: Natural stone masonry units 3 Principle After drying to constant mass and calculating the bulk and impermeable volume, the bulk and real density of the units are calculated. 4 Symbols m, is the mass of the saturated specimen, (g) m,., , is the mass of the dry specimen,
18、(g) m, is the apparent mass of the specimen immersed in water, (8) V, is the bulk volume, (mm3) V, is the volume of open pores, (mm3) V, is the impermeable volume, (mm3) p?, is the real density of the specimen, (kg/m3) Page 4 EN 772-4 : 1998 ph, is the bulk density of the specimen, (kg/m3) mL , is t
19、he mass of the crushed portion, (8) V, , is the volume of liquid displaced by the crushed portion, (mi) P, P is the open porosity, (%) is the total porosity, (%) p, is the density of water, (kg/m3) 5 Materials Deionised water 6 Apparatus 6.1 A ventilated oven capable of maintaining a temperature of
20、70C f 5C . 6.2 An evacuation vessel capable of maintaining a pressure of 2,O kPa f 0,7 kPa. 6.3 A weighing instrument capable of weighing the specimens to an accuracy of at least 0,Ol % of their mass. 6.4 A linear measuring device with an accuracy of 0,l mm. 6.5 A Le Chatelier type flask consisting
21、of a flat-bottomed flask with a tube graduated fiom O to 24 nil in O, ml graduations. 6.6 A sieve with a O, 1 mm mesh. 7 Preparation of the specimens 7.1 Sampling The method of sampling shall be in accordance with prEN 771-6. The minimum number of specimens shall be five, but a larger minimum number
22、 may be specified in the product specification, in which case that larger number shall be used. 7.2 Test specimen The test specimens may have the form of a cylinder, cube or prism and shall be obtained by diamond sawing or coring. Their volume shall be at least 25 cm3. In addition, the surface area
23、to volume ratio shall be between 0,l and 0,2 mm-. 7.3 Preparation of specimens Dry the specimens at a temperature of 70C f 5C to constant mass (6.1). Constant mass is reached if, during the drying process in subsequent weighings with not less than a 24 h interval, the loss in mass between two determ
24、inations is less than 0,l % of the mass. Page 5 EN 772-4 : 1998 8 Procedure 8.1 Open porosity and bulk (apparent) density Weigh the specimens (Q), then place them in an evacuation vessel (6.2) and lower the pressure gradually to 2,O Ea f 0,7 kPa ( = (15 f 5) mm Hg). Maintain this pressure constant f
25、or 24 h in order to eliminate the air contained in the open pores of the specimens. Introduce deionised water at 20C f 5C slowly into the vessel. The rate at which the water rises shall be such that the samples are completely immersed in not less than 15 min. Maintain the pressure of 2,O kPa i 0,7 E
26、a during introduction of the water and for 24 h afterwards. At the end of this period return the vessel to atmospheric pressure and leave the specimens under water for another 24 h at atmospheric pressure. Record the apparent mass in water (mW, ) for each specimen and quickly wipe with a damp cloth
27、and determine the mass (m,cut,) of the specimen saturated with water. In the case of natural stones with visible cavities (e. g. travertine) the apparent volume is determined by measuring their dimensions to the nearest 1 mm. 8.2 Real density Having determined the apparent density and the open poros
28、ity, crush each specimen separately until the particles pass through the sieve (6.6). Dry the crushed specimen to a constant mass and set apart a portion (n,. ) of approximately 50 g (weighed to an accuracy off 0,l g). Introduce deionised water into the Le Chatelier flask (6.5) until the level is up
29、 to the zero graduation. Then add the weighed portion of each specimen into the flask in five fractions each of approximately log ensuring that all of each fraction falls into the liquid. After the introduction of each fraction, agitate the liquid to disperse the crushed specimen. Read the graduatio
30、n to determine the volume ( Fc,.v ) (in ml to the nearest 0,l mi) of liquid displaced by the mass(nIc,.,) of crushed portion. Before taking the initial and final volume readings make sure that the ambient air temperature is 20C zt 5 OC. 9 Calculation and expression of results 9.1 General The volume
31、of the open pores (in mm3) is expressed to the nearest 1 mm3 by equation (1): . (i) The bulk volume (in mm3) is expressed to the nearest 1 mm3 by equation (2): Page 6 EN 772-4 : 1998 .( 2) which can alternatively be calculated on the basis of the dimensions of the specimen. NOTE: The value of the de
32、nsity of water b) a description of the specimens to prEN 77 1-6, the name and address of the client, and: - the type of stone - the commercial name of the stone - the country and region of extraction - the name of the supplier c) the method of sampling and by which organization; d)the direction of a
33、ny bedding or anisotropic features, to be clearly indicated on the samples by means of two parallel lines; e) the date of delivery of the specimens; f) the date of testing; g) the number of specimens in the sample; h) for each sample: the real density and the bulk (apparent) density to the nearest 1
34、0 kg/m3, the open porosity and the total porosity to the nearest 0,l YO. i) the arithmetic mean of the individual values for the real density and for the bulk (apparent) density (to the nearest 10 kg/m3), for the open porosity and for the total porosity (to the nearest O,i%). j) remarks, if any. Pag
35、e 8 EN 772-4 : 1998 Ground glass stopper Have two 0,l ml extend above 1 and below O mark Capacity of bulk approx 250 ml 90 / c Note: Variations of a few millimetres in such dimensions as total height of flask, diameter of base, etc., are to be expected and should not be considered sufficient cause for rejection. Figure 1: Le Chatelier flask for measurement of real densiy
