Casting mortar (grouting mortar) is a thin-flowing, usually low-shrinkage mortar used to completely fill voids, joints and connections. Because the mortar flows well, it fills every space and produces a dense, load-bearing connection without air pockets.
Application
Casting mortar is used, among other things, to bed steel structural components such as the base plates of columns on a foundation. Filling recesses around anchors, fixing machine feet and grouting precast concrete elements is also done with casting mortar. In restoration, a fluid mortar is used to inject voids in masonry.
Many casting mortars are low-shrinkage or slightly expansive: they expand a little as they cure, so the void stays fully filled and contact is made with the surrounding parts.
Characteristics
The most important property is the high fluidity, which lets the mortar distribute and de-aerate itself. Compressive strength also matters, because casting mortar often has to transfer forces between structural components. Closely related products are grout (for anchors and piles) and casting concrete. When placing it, the correct amount of mixing water and good curing are important to prevent cracks.
Related terms
- mortar
- grout
- grout injection
- mortar mix
- concrete mortar
- bearing
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