Sealing the crack surface before injection
The surface layer helps limit outflow of the injection material. The interior of the crack is filled with a separately selected material.
CRACK PREPARATION AND SEALING
CrackOn.5
Fast-setting mortar for locally stopping seepage, closing holes and crack surfaces, and rapidly fixing elements in concrete.
| Preparation | 200 ml of water per 1 kg of dry mix |
|---|---|
| Delivery method | By hand; use immediately after mixing |
| Working time | 4 min at 25°C; 7 min at 7°C |
| Grain size | 0.06–0.8 mm |
| Application temperature | Material, ambient and substrate temperature +5 to +30°C |
Technical data
Read values together with the temperature, material state and test conditions.
| Compressive strength after 1 h / 28 days | 10 / 38 MPa |
|---|---|
| Flexural strength after 1 h / 28 days | 1.5 / 5.5 MPa |
| Pull-off adhesion after 28 days | > 1.1 MPa to a concrete substrate |
| Water ratio | 200 ml/kg of dry product |
| Indicative yield | 15 kg of dry product yields approximately 7.5 l of fresh mortar |
The product name and the statement “sets in 5 min” do not replace the temperature-dependent working time. Yield refers to prepared mortar; it is not the density of the dry powder.
- Storage and shelf life
- Dry, cool place away from sunlight; 12 months in the original, unopened packaging.
Applications and selection criteria
First establish the repair objective, substrate condition, presence of water and joint movement.
Local seepage and holes
Rapid filling in concrete and temporary water stopping. Select a quantity that can be placed before the mortar loses workability.
Rapid fixing of elements
The TDS covers steel elements in concrete and horizontal, vertical and overhead surfaces. Fixing capacity must be selected for the task.
Application conditions and limitations
Closing the crack surface does not confirm that its cross-section is filled. At a moving joint, the mortar may serve only the role specified in the method, such as a temporary closure removed after injection; it must not rigidly block the required movement.
How the material behaves
Damp substrate and local seepage; measured mixing water quantity. Rigid mortar; does not replace flexible expansion joint sealing.
1. Batch
Dry mortar + measured water
2. Manual placement
Pressing in and holding
3. Function
Local or surface closure
Preparation and application
Work sequence after assessing the structure and selecting the method. Full requirements are given in the product instructions.
Clean and prepare the substrate
Remove contaminants and loose fragments. The TDS recommends opening the crack to at least 10 mm in width and depth; adapt the work to the element.
Dampen without leaving excess water
Clean exposed steel and prepare a substrate that provides adhesion. Remove excess water before placement.
Mix a small batch
Measure 200 ml of water per 1 kg of powder. Mix by hand for approximately 15–30 s until homogeneous and use immediately after preparation.
Press in and hold until hardened
Fill the target area without voids. Adjust the quantity and preparation cycle to the temperature; higher temperatures shorten the working time.
From selection to application
Choose the instructions for your task and calculate material quantities using clearly defined assumptions.
Product documentation
Data, application instructions and safety documents for the supplied material.
Preparing for safe work
Before use, read the current documentation for all supplied components. Select protective equipment, ventilation and cleaning methods appropriate to the material and equipment.
Discuss your project conditions
Prepare a description of the substrate, water, geometry and expected result. Let us select the material and delivery method.