Product terminology
Expansive grout – meaning, use and distinction
Expansive grout and expansive mortar are used almost interchangeably. Grout implies a thinner mix that flows freely into narrow or deep holes.
What does the term mean?
Expansive grout is a water-mixed mineral slurry that fills a borehole completely and then expands. The word grout is borrowed from grouting work, where a fluid mix is pumped into cavities.
The product is identical to an expansive demolition agent; only the description of the consistency differs.
Where does the name come from?
Civil engineering has used grout for decades to describe injectable, cement-based mixes. When expansive agents were pumped rather than poured, the same word travelled with the method.
The term is more common in North America and in tunnelling than in general building work.
Where is the term used?
Used mainly where the material is pumped or where deep boreholes have to be filled without air pockets.
Also found in mining and tunnelling documents, alongside injection and grouting terminology.
- Tunnelling and mining
- Deep boreholes and pumped application
- North American product literature
- Specialist civil engineering
Is the term technically unambiguous?
Not entirely. Grout usually means a filling material that strengthens a structure – here it does the opposite and breaks it apart.
In documents that mix grouting and demolition work, add the word expansive or use expansive demolition agent to avoid confusion.
How does the product work?
Mixed slightly more fluid than a hand-poured mortar, the grout is pumped through a hose to the bottom of the hole so that the hole fills from below and no air is trapped.
Expansion pressure then develops in the same way as with a hand-mixed batch. Equipment and calibration are described in mechanical application.
Typical applications
- Deep boreholes over three metres
- Large-volume rock excavation
- Tunnel and shaft profiling
- Underwater applications
- Series drilling with many holes
Compared with related names
Expansive mortar
The same product with a stiffer, hand-poured consistency.
Read moreExpansive demolition agent
Umbrella term independent of consistency.
Read moreRock splitting agent
Focuses on the application rather than the mix.
Read moreSCDA
Soundless Chemical Demolition Agent
Research term for the same chemistry.
Read moreBETONAMIT® and this term
BETONAMIT® can be mixed as a pourable grout for pumped application; the water content stays within the range given on the data sheet.
Recommended mixing pumps and calibration values are listed on the mechanical application page.
Frequently asked questions
+What is the difference between expansive grout and expansive mortar?
Only the consistency. Grout describes a more fluid mix, mortar a stiffer one; the product and the chemistry are the same.
+Can expansive grout be pumped?
Yes, that is its main advantage. A mixing pump fills deep holes from the bottom upwards and keeps the consistency constant.
+Does a more fluid mix reduce the pressure?
Adding more water than specified does reduce performance. Stay inside the range given on the data sheet.
More product names
Expansive mortar
Describes the product in its mixed state: a pourable mortar that expands inside the borehole.
Read moreExpansive demolition agent
The umbrella term preferred by KUBATEC in English for products that split rock, stone and concrete by controlled expansion pressure.
Read moreRock splitting agent
The same product group described from the quarrying and excavation side.
Read moreChemical demolition agent
Generic wording that separates chemically acting products from mechanical demolition.
Read moreSCDA
Soundless Chemical Demolition Agent
The standard term in academic research and testing literature, emphasising silent, chemical demolition.
Read moreQuestions about the right term or the product?
We have advised planners, contractors and distributors on non-explosive demolition for over 50 years – from drill pattern to pack size.