1. Chapter 5
Construction Mortar

2. §5.2 The composites of Mortar
Chapter 5
§5.2 The composites of Mortar
Cement
Sand
Lime

3. The Composites of Mortar
The composites of mortar do not include coarse aggregate, while other materials are similar to concrete
Including
Cement
Sand
Lime

4. The Composites of Mortar
Cement
Cement types
The six common kinds of cement can all be used in mixing masonry mortar；
But for special uses such as component adapter, structure reinforcement, crack mending, it can use expansion cement.
Strength grade
Low strength grade cement is usually used;
However, right amount of mixed material can be added when the grade is too high

5. The Composites of Mortar
Sand
Sand used in mortar is different from the sand of concrete, the differences are:
Limitations for maximum of sand particle diameter
When used for rubble masonry
Dmax<1/4～1/5 thickness of mortar layer
When used for brickwork
Medium Sand: Dmax≯2.5mm
When used for smooth flour-milling jointing
Fine Sand only

6. The Composites of Mortar
Sand
Limitations for clay content
In order to ensure mortar quality, especially high strength mortar, there are the following limitations for clay quantity of sand
Above M2.5, Impurity quantity of clay: 5%
Below M2.5, Impurity quantity of clay: 10%

7. The Composites of Mortar
Sand
Limitations for clay content
Furthermore, aggregate can be formed with manufactured sand, hilly sand, furnace slag and so on;
The technical index of mortar can be fixed according to experience or experiment.

8. The Composites of Mortar
Lime
In order to save cement and improve workability, right amount of lime or clay can be added.
Lime must be made into lime paste (consistency 120mm) first, and quicklime powder or slaked lime powder can sometimes be straightly used.