photo.jpg

## SANS 2001-CM1:2007 - Edition 1 ### 4.2.1.2 Mortar Unless otherwise specified in the specification, no mortar plasticizers or set-retarding admixtures shall be added to the mixes to improve workability or to improve the properties of the mortar. The types of sands and cement in a strength mort...

## SANS 2001-CM1:2007 - Edition 1 ### 4.2.1.2 Mortar Unless otherwise specified in the specification, no mortar plasticizers or set-retarding admixtures shall be added to the mixes to improve workability or to improve the properties of the mortar. The types of sands and cement in a strength mortar shall not be altered during the construction of the works unless tests indicate that such changes allow the required strength to be achieved. The method used for measuring materials for mortar shall be such that the proportions of the constituent materials can be controlled and consistently maintained. ### 4.2.2 Prescribed-mix mortar Mortar shall have the mix proportions given in table 7. | Cement type | Cement (kg) | Lime (kg) | L max. | Number of standard wheelbarrows | |---|---|---|---|---| | **Class I mortar** | | | | | | Common cements | 50 | 0 - 10 | 130 | 2 | | Masonry cement MC 22.5 X, MC 12.5 | 50 | Not permitted | 80 | 1 | | **Class II mortar** | | | | | | Common cements | 50 | 0 - 25 | 200 | 3 | | Masonry cement MC 22.5 X, MC 12.5 | 50 | Not permitted | 130 | 2 | ***NOTE*** Cement should not be measured by volume. A bag of common cement, depending on the quantity of extenders, has a mass of 50 kg and a volume of approximately 33 L when packed under air pressure at the factory. Cement, however, fluffs up (bulks) when poured into a container, with the result that 50 kg of cement cannot readily be contained in a box of 33 L. The volume of a bag of loose (bulked) cement, depending upon its compaction, can be up to 20% more than when in the bag. For this reason it is always preferable to use whole bags of cement when volume batching. ***a*** The addition of lime to common cements is optional, subject to the maximum amount given in table 7. Lime shall not be used to replace a portion of the cement in the mix. ***b*** A standard wheelbarrow for concrete that complies with SANS 795 (type 2) has a capacity of between 60 L and 70 L.