KENYA STANDARD                     KS 2177:  2017 
                
   
KENYA STANDARD          KS 2769 -13:2018  
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
Admixtures for concrete, mortar and grout 
Test methods Part 13: Reference masonry 
mortar for testing mortar admixtures  
 
 
 
 
 
 
©KEBS 20 18                        First Edition  2018 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 KS 2177: 2017                                                                                                            
 
ii                     © KEBS 2017 — All rights reserved  TECHNICAL COMMITEE REPRESENTATION  
 
The following organizations were represented on the Technical Committee:  
 
1. Architectural Association of  Kenya  
2. Bamburi Cement  
3. CHRYSO Eastern Africa Limited  
4. Concrete Products (K)Ltd  
5. Consumer Information Network  
6. Howards Humpre ys East Africa LTD  
7. Institute of quantity surveyors of Kenya  
8. Kenya Industrial Research and Development Institute (KIRDI  
9. Kenya Institute of Highways and Building Technology (KIHBT)  
10. Ministry of Transport, Infrastructure, Housing and Urban Development.  
11. Nationa l Environment Management Authority  
12. National Housing Corporation  
13. Technical University of Kenya  
14. University of Nairobi  
15. Kenya Bureau of Standards — Secretariat  
 
 
 
 
 
 
 
 
 
 
 
REVISION OF KENYA STANDARDS  
 
In order to keep abreast of progress in industry, Kenya Stan dards shall be regularly reviewed. Suggestions 
for improvements to published standards, addressed to the Managing Director, Kenya Bureau of Standards, 
are welcome.  
 
 
 
 
 
 
 
 
 
 
© Kenya Bureau of Standards, 20 17 
  
Copyright. Users are reminded that by virtue o f Section 25 of the Copyright Act, Cap. 12 of 2001  of the Laws of Kenya, copyright 
subsists in all Kenya Standards and except as provided under Section 26 of this Act, no Kenya Standard produced by Kenya Bure au of 
Standards may be reproduced, stored in a retrieval system in any form or transmitted by any means without prior permission in writing 
from the Managing Director . 
 
 
 
 
 
 
 
 
 
 
 
 KENYA STANDARD                                  KS 2177 : 2017 
                
 © KEBS 2017 — All rights reserved            iii  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Admixtures for concrete, mortar and grout 
Test methods Part 13: Reference masonry 
mortar for testing morta r admixtures  
 
 
 
 
 
 
 
 
 
KENYA BUREAU OF STANDARDS (KEBS)  
 
Head Office:  P.O. Box 54974, Nairobi -00200, Tel.: (+ 254 020 ) 605490, 602350, Fax: (+254 020 ) 604031  
E-Mail: info@kebs.org,  Web:http://www.kebs.org   
 
Coast Region     Lake Region          Rift Valley R egion  
P.O. Box 99376, Mombasa -80100   P.O. Box 2949, Kisumu -40100        P.O. Box 2138, Nakuru -20100  
Tel.: (+ 254 041 ) 229563, 230939/40  Tel.: (+254 057) 23549, 22396        Tel.: (+254 051) 210553, 210555  
Fax: (+254  041) 229448    Fax: (+254 057) 21814         
 
 
 
 
 
 
 
 KS 2177: 2017                                                                                                            
 
iv                     © KEBS 2017 — All rights reserved   
Foreword  
 
This Kenya Standard was revised  by the Concrete Technical Committee, under the guidance of the 
standards Projects Committee, and it is in accordance with the procedures of the  Kenya  Bureau  of 
Standards .  
This Kenya Standard is part of t he series KS 2769  Admixtures for concrete, mortar and grout — Test 
methods which comprise  the following:  
 
— Part 1: Reference concrete and reference mortar for testing  
 
— Part 2: Determination of setting time  
 
— Part 4: Determination of bleeding of concret e 
 
— Part 5: Determination of capillary absorption  
 
— Part 6: Infrared analysis  
 
— Part 8: Determination of the conventional dry material content  
 
— Part 10: Determination of water soluble chloride content  
 
— Part 11: Determination of air void characterist ics in hardened concrete  
 
— Part 12: Determination of the alkali content of admixtures  
 
— Part 13: Reference masonry mortar for testing mortar admixtures  
 
— Part 14: Determination of the effect on corrosion susceptibility of reinforcing steel by potentiost atic 
Electro -chemical  test 
 
— Part 15: Reference concrete and method for testing viscosity modifying admixtures  
 
This standard is applicable together with the standards of the series KS 2770  Admixtures for concrete, 
mortar  and grout.  
 
. 
 
                          KS 2177: 
2017  
 
 
© KEBS 2017 — All rights reserved         
      5 
 BRITISH STANDARD  
KENYA  STANDARD                       KS 2769 -13:2018  
 
Admixtures for concrete, mortar a n d  g r o u t  T e s t  
methods Part 13: Reference masonry mortar for testing mortar 
admixtures  
 
1. Scope  
 
This Standard specifies the constituent materials, the composition and the mixing procedu re to 
produce a reference masonry mortar with a prescribed consistence for testing mortar admixtures as 
defined in KS 2770 . It also describes the determination of the water reduction of the test mix compared 
to the control mix. 
 
2.  Normative references  
 
The following documents, in whole or in part, are normatively referenced in this document and 
are indispensable for its application. For dated references, only the edition cited applies. For undated 
references, the latest edition of the referenced document (in cluding any amendments) applies.  
 
KS EAS 148 -1-2016: Cement — Test methods — Part 1: Determination of strength  
KS EAS 148 -2-2016: Cement — Test methods — Part 2: Chemical analysis  
KS EAS 148 -6-2016: Cement — Test methods — Part 6: Determination of fineness  
KS EAS 18 -1, Cement - Part 1: Composition, specifications and conformity criteria for common cements  
KS 2770 -3, Admixtures for concrete, mortar and grout — Part 3: Admixtures for masonry mortar — Definitions, 
requirements, conformity, marking and labelling  
EN 1008, Mixing water for concrete - Specification for sampling, testing and assessing the suitability of water, 
including water recovered from processes in the concrete industry, as mixing water for concrete  
EN 1015 -4, Methods of test for mortar for maso nry - Part 4: Determination of consistence of fresh mortar (by 
plunger penetration)  
EN 1015 -7, Methods of test for mortar for masonry - Part 7: Determination of air content of fresh mortar  
 
3.  Constituent materials  
 
3.1. Cement  
 
The reference masonry mortar shall  be made with CEM I cement of strength class 42.5 or 52.5, 
conforming to KS EAS 18 -1. 
 
The cement used shall have a C 3A content of 7 % to 11 % by mass calculated from chemical 
analysis according to KS EAS 148 -2 and a specific surface of (3 200 to 4 600) cm2/g determined 
according to KS EAS 148 -6. 
 
3.2.  Sand  
 
A natural sand of normal density (relative density 2.5 – 2.8) shall be used. The size fractions of the sand 
shall comply with  
 
Table 1. The sand shall be used in an oven dry condition.  
Aperture size  
(mm)  Percentage by mass  
passing the test sieve  
4.0 100 
2.0 90– 100 
1.0 60– 90 
0.5 40– 75 KS 2 177: 2017  
            
                              © KEBS 2017 — All rights 
reserved  6 0.25 25– 50 
0.125  10– 30 
0.063  0– 10 
 
3.3. Mixing water  
 
Water according to EN 1008  shall be used as mixing water.1) 
 
4.  Reference masonry mortar  
 
Where specified, tests on reference mortar are performed as comparative tests. That is comparing the 
performance of the reference mortar containing an admixture (test mix) with the performance of the 
reference mortar without an admixture (control mix). The air content of the con trol mix shall not exceed 
5 % by volume when determined in accordance with EN 1015 -7, method A.  
 
5.  Production of reference mortar with standard consistence  
 
5.1. Mix proportions  
 
The control and test mixes shall be in accordance with Table 2.  
Table 2 — Mix deta ils 
 Control mix  Test mix  
Sand  3 440 g  3 440 g  
Cement  640 g  640 g  
Admixture  Nil Compliance Dose  
Water  As required  As required  
Consistence measured  
according to EN 1015 -4 (40 ± 5) mm  Within ± 3 mm of consistence of  
control mix  
 
Record to the nearest  1 g the total quantity of water required (including any contributed by the 
admixture).  
 
For test mix mortars, the quantity of admixture added shall be sufficient to produce the required air 
content and retardation time if appropriate. The dose of admixtur e shall be recorded.  
 
5.2. Mixing procedure  
 
Prior to mixing, each of the constituents shall be conditioned to a temperature of (20 ± 2) °C.  
 
Place all the sand and then the cement in the mixing bowl of a mixer complying with KS EAS 148 -1 and 
mix for 30 s at low speed.  
 
Continue mixing and add half of the mixing water during the next 30 s and mix for a further 60 s.  
 
During a further 30 s of mixing, add the third quarter of the water and the admixture2).  
 
During a further 30 s of mixing, add the final quart er of the mixing water. If necessary, the quantity of 
water shall be adjusted to obtain the required consistence.  
                                                      
1 Distilled or ionized water can be used in special cases  
2 If recommend ed by the manufacturer, admixtures can be added at a different time in the mixing 
sequence.  
 
 
                          KS 2177: 
2017  
 
 
© KEBS 2017 — All rights reserved         
      7 
  
Continue mixing at low speed for 60 s after all the water has been added.  
 
Stop the mixer for 60 s and during this time remove any unmixed material from the sides and bottom of 
the bowl using the mixer paddle.  
 
Restart the mixer at high speed and mix for 60 s. Total mixing process time shall be 6 min.  
 
Immediately after completion of mixing, the consistence shall be determined in accordance  with EN 
1015 -4 and the air content in accordance with EN 1015 -7, method A. If the required consistence and air 
content are not achieved, the mix shall be discarded. A new test mix shall be prepared with the water 
content adjusted.  
 
5.3. Mortar for test after standing  
 
Prepare a test mix as described in 5.1 and 5.2. Cover the mixing bowl to prevent loss of water by 
evaporation and allow to stand for the period of time prescribed in KS 2770 -3. After the required standing 
period from completion of mixing, remix the mortar in the bowl for 10 s using a palette knife.  
 
5.4. Mortar for test after extended mixing  
 
Prepare a test mix as described in 5.1 and 5.2. Then continue mixing at low speed for a further 15 min.  
 
6.  Calculation of water reduction (air entraining/plast icizing admixtures)  
 
Calculate the percentage water reduction, W, resulting from inclusion of the admixture, from the following 
formula:  
 
where  
 
C is the water requirement of the control mix in g;  
 
T is the water requirement of the test mix in g.  
The water reduction shall be reported to the nearest 1 %.  
  
7. Test report  
 
The test report shall include the following information for control and test mixes:  
 Cement:  
 Factory where produced;  
 T yp e ;  
 C3A content;  
 Specific surface area;  
 S a n d :  
 Source;  
 T yp e ;  
 Grading ; 
 Consistence;  
 Air content;  
 Water content of each mix;  
 Water reduction of test mix (for air entraining/plasticizing admixtures);  
 Admixture name, batch/reference number and dose in g.