How to solve the pinhole of self-leveling itself?

[Scott Kaplan]

I have been using Microsilica for self-leveling these days. After measuring its fluidity, the surface is densely packed with pinholes, which look very dense. What is the problem? Here is the formula,

ordinary portland cement: 275
calcium sulphoaluminate: 125
bassanite: 30
Anhydrite(12.5 80-100 mesh): 450
limestone powder: 150
Microsilica: 38
Polycarboxylate superplasticizer: 1.5
antifoaming agent: 0.6 400
CPS: 0.7
Tartaric acid: 1.2
Sodium gluconate: 0.5
Coagulant: 0.7
Redispersible Polymer powder: 12
Initial fluidity: 150mm

 

[Cassie]

First of all, this is not a problem of Microsilica, which has the function of anti-sedimentation and reinforcement and has little effect on the surface.

In your formula, the amount of fine powder is a bit too much; you see, binding material+cement + gypsum + microsilica is close to 600 kg. Your water-reducing agent is also used in large amounts.

Looking at the surface, it is not clear whether there is bleeding, but pores and sand grains are on the appearance, which is not good. Although the leveling property is large, there should be bleeding since the amount of fine powder is large, which may be obscure.

Recommend you control the amount of your binding material; it is currently too high.

Moreover, it is normal for self-leveling to have air bubbles or pinholes, so how can there be no air holes at such a high water-reducing rate?

The anti-foaming agent in the mortar is entirely different from that in the water-based paint. Sometimes, the performance of the anti-foaming agent is too good will causing the bubbles to float to the surface, and the problem becomes more serious. The effect of an anti-foaming agent is minimal.

 

[Chanliss]

Try to take away the Microsilica.

 

[Alex]

Sodium gluconate has a good retarding effect, but the performance on the surface is not very good, and it is easy to bleed. So recommend you not to add sodium glucose to self-leveling.

 

[Ramon Doria]

Limestone powder and Sodium gluconate are redundant.