BS EN 1052-4-2000 Methods of test for masonry - Determination of shear strength including damp proof course《圬工的试验方法 包括防潮层的剪切强度的测定》.pdf

1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 1052-4:2000 The Eur

2、opean Standard EN 1052-4:2000 has the status of a British Standard ICS 91.080.30 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Methods of test for masonry Part 4: Determination of shear strength including damp proof courseThis British Standard, having been prepared under the

3、 direction of the Sector Committee for Building and Civil Engineering, was published under the authority of the Standards Committee and comes into effect on 15 September 2000 BSI 09-2000 ISBN 0 580 36530 1 BS EN 1052-4:2000 Amendments issued since publication Amd. No. Date Comments National foreword

4、 This British Standard is the official English language version of EN 1052-4:2000. The UK participation in its preparation was entrusted by Technical Committee B/519, Masonry and associated tests, to Subcommittee B/519/4, Tests, which has the responsibility to: aid enquirers to understand the text;

5、present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtai

6、ned on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” fa

7、cility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary 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 obli

8、gations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 12, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.EUROPEAN STANDARD NORME EUROPENNE EUROPISCH

9、E NORM EN 1052-4 May 2000 ICS 91.080.30 English version Methods of test for masonry - Part 4: Determination of shear strength including damp proof course Mthodes dessai de la maonnerie - Partie 4: Dtermination de la rsistance au cisaillement, en tenant compte de la couche de coupure de capillarit Pr

10、fverfahren fr Mauerwerk - Teil 4: Bestimmung der Scherfestigkeit bei einer Feuchtesperrschicht This European Standard was approved by CEN on 22 April 2000. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the s

11、tatus of a national 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).

12、A version in any other 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

13、, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Central Secretariat: rue de Stassart, 36 B-1050 Brussels

14、2000 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1052-4:2000 EPage 2 EN 1052-4:2000 BSI 09-2000 Contents Page Foreword 3 1 Scope . 4 2 Normative references. 4 3 Principle 4 4 Definitions and symbols 5 5 Materials 6 6 Apparatus.

15、 6 7 Preparation and curing of specimens. 7 8 Procedure. 8 9 Calculations. 9 10 Evaluation of results 9 11 Test report . 10 Bibliography. 12Page 3 EN 1052-4:2000 BSI 09-2000 Foreword This European Standard has been prepared by Technical Committee CEN/TC 125, Masonry, the Secretariat of which is held

16、 by BSI. 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 November 2000, and conflicting national standards shall be withdrawn at the latest by November 2000. According to the CEN/CENELEC Internal

17、Regulations, 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

18、the United Kingdom.Page 4 EN 1052-4:2000 BSI 09-2000 1 Scope This European Standard specifies a method for determining the in plane shear strength of horizontal bed joints in masonry incorporating sheet damp proof course material using a specimen tested in double shear with load applied perpendicula

19、r to the bed joints. Guidance is given on the preparation of the specimens, the conditioning required before testing, the testing machine, the method of test, the method of calculation and the contents of the test report. 2 Normative references This European Standard incorporates by dated or undated

20、 reference, provisions from other publications. 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 inc

21、orporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. prEN 772-1 Methods of test for masonry units - Part 1: Determination of compressive strength. EN 772-10 Methods of test for masonry units - Part 10: Determination of moisture c

22、ontent of calcium silicate and autoclaved aerated concrete units. prEN 998-2 Specification for mortar for masonry - Part 2: Masonry mortar. EN 1015-3 Methods of test for mortar for masonry - Part 3: Determination of consistence of fresh mortars (by flow table). EN 1015-7 Methods of test for mortar f

23、or masonry - Part 7: Determination of air content of fresh mortar. EN 1015-11 Methods of test for mortar - Part 11: Determination of flexural and compressive strength of hardened mortar. 3 Principle The shear strength of masonry incorporating sheet damp proof course material is derived from the stre

24、ngth of small masonry specimens tested to destruction. The specimens are tested in double shear under three-point load with precompression perpendicular to the bedjoints. The shear strength is defined by the initial shear strength and the coefficient of friction.Page 5 EN 1052-4:2000 BSI 09-2000 4 D

25、efinitions and symbols 4.1 Definitions For the purposes of this standard, the following definitions apply: 4.1.1 masonry: an assemblage of masonry units laid in a specified pattern and jointed together with mortar 4.1.2 shear strength of masonry: the strength of masonry subjected to shear forces 4.2

26、 Symbols A i is the cross-sectional area of the masonry specimen parallel to the bed joints, (mm 2 ) F i,max is the maximum shear load withstood by an individual masonry specimen, (N) f vi is the shear strength of an individual masonry specimen at a particular precompressive stress, (N/mm 2 ) f pi i

27、s the precompressive stress, (N/mm 2 ) F pi is the precompressive load, (N) f vim is the mean shear strength of the three masonry specimens tested at a particular precompressive stress, (N/mm 2 ) f vo is the mean value of shear strength at zero precompressive load, (N/mm 2 ) f vck is the characteris

28、tic value of shear strength, (N/mm 2 ) l is the length of the specimen, in mm h is the height of the specimen, in mm w is the width of the specimen, in mm is the angle of internal friction, in degrees k is the characteristic angle of internal friction, in degreesPage 6 EN 1052-4:2000 BSI 09-2000 5 M

29、aterials 5.1 Masonry units 5.1.1 Conditioning of the units The conditioning of masonry units shall be as specified. Measure the moisture content by mass of autoclaved aerated concrete and calcium silicate masonry units in accordance with EN 772-10. For other types of masonry unit record the method o

30、f conditioning the units prior to laying. Record the age of non-autoclaved concrete units at the time of testing the masonry specimens. 5.1.2 Determination of the compressive strength of the masonry units Determine the compressive strength of a sample of masonry units, using the test method given in

31、 prEN 772-1. For non-autoclaved concrete units determine the compressive strength at the time of testing the masonry specimens. 5.2 Mortar The mortar, its mixing procedure and its flow value shall conform with the requirements of prEN 998-2, unless otherwise specified, and these shall be reported in

32、 the test report. Take representative samples of fresh mortar from the masons board to make mortar prism specimens, to determine the flow valve in accordance with prEN 1015-3 and to determine the air content in accordance with prEN 1015-7. Use the prism specimens to determine the mean compressive st

33、rength at the time of testing the masonry specimens in accordance with prEN 1015-11. 6 Apparatus 6.1 The testing machine used to apply the shear loads and precompression shall comply with the requirements given in Table 1. The testing machine shall have adequate capacity but the scale used shall be

34、such, that the ultimate load on the specimen exceeds one fifth of the full scale reading. The machine shall be provided with a load pacer or equivalent means to enable the load to be applied at the rate specified. 6.2 Apparatus capable of measuring the cross-sectional area of the specimens to an acc

35、uracy of 1 %. Table 1 - Requirements for testing machines Maximum permissible repeatability of forces as percentage of indicated force Maximum permissible mean error of forces as percentage of indicated force Maximum permissible error of zero force as percentage of maximum force of range 2,0 2,0 0,4

36、Page 7 EN 1052-4:2000 BSI 09-2000 7 Preparation and curing of specimens 7.1 Preparation of masonry specimens Prepare at least nine specimens in the format shown in Figure 1. The length of the specimens shall be greater than 400 mm and less than 700 mm. The height to width ratio (h/w) shall be greate

37、r than 2 and there should be at least one vertical joint per course. 1 2 3 4 5 6 7 8 Key 1 Straw-board 2 Shear load 3 Damp proof courses 4 Compressive load 5 Upper platen 6 Load spreading material 7 Rigid abutments to restrain top and bottom courses (adjustable to allow for minor variations in mason

38、ry) 8 Lower platen Figure 1 - Testing arrangement The damp proof course shall be sandwiched between layers of mortar. Frogs and perforations shall not be exposed at the end of the specimen but turned in. Build the specimens on a flat horizontal surface. The units shall be laid so that a final mortar

39、 joint thickness of 8 mm to 15 mm representative of masonry with conventional mortar joints, of 1 mm to 3 mm representative of masonry made with thin layer mortar joints is attained. The masonry unit shall be checked for linear alignment and level using a set-square and spirit level. Excess mortar s

40、hall then be struck off with a trowel. The procedure shall be repeated for the top unit(s).Page 8 EN 1052-4:2000 BSI 09-2000 7.2 Curing and conditioning of the specimens Immediately after building, pre-compress each specimen using a uniformly distributed mass to give vertical stress between 2,0 10 -

41、3N/mm 2and 5,0 10 -3N/mm 2 then cure the specimens and maintain them undisturbed until testing. For other than lime-based mortar, prevent the test specimens from drying out during the curing period by close covering with polyethylene sheet, and maintain the specimens undisturbed until testing unless

42、 otherwise specified. Test each specimen at an age of 28 days 1 day, unless otherwise specified for lime-based mortar, and determine the compressive strength of the mortar at the same age, following EN 1015-11. 8 Procedure 8.1 Placing the specimens in the testing machine Place the specimens in the t

43、esting machine and apply the compressive load and the shear load as shown in Figure 1. The faces of the masonry units where the shear load is to be applied shall be plane and perpendicular to the direction of the shear load. 8.2 Loading Test at least three specimens at each of three precompression l

44、oads. Use precompression loads that give stresses of approximately 0,2 N/mm 2 , 0,6 N/mm 2and 1,0 N/mm 2 .The precompression load shall be kept within 2% of the initial value. Increase the shear stress at a rate between 0,1 N/mm 2and 0,4 N/mm 2per min. 8.3 Measurements and observations Record the fo

45、llowing: - the age of non-autoclaved concrete units; - the cross-sectional area A iof the specimens parallel to the shear force with an accuracy of 1 %; - the precompression load F pi ; - the load F i,max where failure of one of the bed joints occurs; - the mode of failure, e.g. slipping along damp

46、proof course or material failure within the damp proof course.Page 9 EN 1052-4:2000 BSI 09-2000 8.4 Replications If failure is by shear failure in the unit parallel with the bed joint or crushing or splitting of the units, then either further specimens may be tested until three shear failures for ea

47、ch precompression level have been achieved or alternatively the result may be used as a lower bound to the shear strength. However, circumstances may be such that the use of an alternative unit is appropriate. 9 Calculations For each specimen at each compressive stress calculate the shear strength t

48、o the nearest 0,01 N/mm 2 using the following formula: 2 i max i, vi N/mm 2A F f Calculate the precompressive stress at each precompression load as: 2 i pi pi N/mm A F f 10 Evaluation of results Plot a graph of the individual shear strength f viagainst the normal compressive stress f pias shown in F

49、igure 2. Plot the line determined from a linear regression of the points. Record the mean initial shear strength f voand the angle of internal friction to the nearest degree, from the slope of the line.Page 10 EN 1052-4:2000 BSI 09-2000 Key 1 Shear strength (N/mm 2 ) 2 Precompressive stress (N/mm 2 ) Figure 2 - Shear strength and angle of internal friction The characteristic value of the initial shear strength with damp proof course is f vckwhere f vck= 0,8 f voand the characteristic angle of internal friction from