Why Concrete Mender™ works…
The Science Behind Roadware
What makes Roadware 10 Minute Concrete Mender™ different starts with how the liquid interacts with concrete. Its low surface tension allows the material to wet the concrete surface and flow readily into tight cracks, fissures, and porous areas. Instead of simply filling the opening at the surface, Concrete Mender™ penetrates into the repair area, helping create a more complete connection with the surrounding concrete.
- Ultimate Surface Tension Test for Concrete Mender
- What is Microdoweling™?
- Concrete Mender™ Bond Strength
Please see Surface Tension testing data below.
University of Illinois at Urbana-Champaign
Department Telephone: (217) 333-4816
Civil Engineering facsimile: (217) 333-9464
email: dlange@uiuc.edu
September 16, 2002
Richard King
Roadware, Inc.
381 Bridgepoint Drive
South St. Paul, MN 55075
Dear Richard,
I am pleased to submit results of our measurement of surface tension of Concrete Mender conducted in accordance with our Wilhelmy Plate Method standard practice. Websites describing the Wilhelmy Plate Method for measuring surface tension include http://www.kibron.com/Science/ and http://www.tensiometry.com/STMethods.htm.
In our implementation of the test, we monitor the weight of a petri dish on an electronic scale as a glass slide is drawn up from a fluid in the petri dish. The weight of the petri dish is reduced by the pulling force of the glass slide on the liquid surface. The weight change is converted to surface tension by a simple equation.
The results of the tests are shown on the attached page. The surface tension of plain water, Concrete Mender Part A (lighter in color) and Part B (darker in color) are reported. Surface tension is reported in units of force/length (e.g. N/m). A summary of the surface tension of Concrete Mender and other reference fluids is shown below:
| Fluid | Surface Tension (N/m) |
| water at 20°C | 0.0729 |
| ethanol | 0.0223 |
| benzene | 0.0289 |
| glycerin | 0.0634 |
| CONCRETE MENDER PART A | 0.026 |
| CONCRETE MENDER PART B | 0.025 |
| CONCRETE MENDER 30-40 s after mixing | 0.026 |
Concrete Mender Parts A and B separately and A/B together soon after mixing exhibit surface tension similar to ethanol. The results also show the material wets concrete surfaces, with a contact angle of 0°.
These findings, with viscosity measurements of about 10 cPs, describe a fluid with favorable wetting. It can be drawn into cracks by capillary action in the first minute after contact.
These physical properties of Concrete Mender are consistent with the observed penetration into concrete substrates, and they support its strong bond with repair surfaces.
Sincerely,
Prof. David A. Lange
Attachment: a) Lab data
| ROADWARE 10 MINUTE CONCRETE MENDER | ||||||
| SURFACE TENSION TEST RESULTS | ||||||
|
plate no |
wide (mm) |
thickness (mm) |
perimeter P (mm) | |||
|
1 |
dark |
25.21 |
0.99 |
52.40 | ||
|
2 |
light |
25.24 |
1.02 |
52.52 | ||
|
3 |
mixed |
25.25 |
1.01 |
52.52 | ||
| s = (F*g*cos q )/P | ||||||
| g =9.807 m/s2 | ||||||
| temperature of water = 200C | ||||||
| surface tension of water is 0.072-0.073 N/m | ||||||
|
Force 1 (kg) |
Force 2 (kg) |
Force 3 (kg) |
Ave. Force (kg) |
P (mm) |
s (N/m) | |
|
water |
0.3901 |
0.3901 |
52.40 |
0.073 | ||
|
dark |
0.1311 |
0.1318 |
0.1320 |
0.1316 |
52.40 |
0.025 |
|
water |
0.3857 |
0.3872 |
0.3852 |
0.3860 |
52.52 |
0.072 |
|
light |
0.1367 |
0.1368 |
0.1364 |
0.1366 | ||