Foam, bleeding, slump loss: fixing concrete problems with the right admixture

Many concrete complaints are solved faster by choosing the right functional admixture than by changing the mix proportions. This is a symptom-to-solution map for the problems we see most often.

Excess foam and high air content

Symptom: honeycomb-looking surface, air content above 3%, pump pressure climbing. Cause is usually residual air from the mixer or an overdose of an air-entraining raw material. A defoamer collapses unstable foam quickly; check your air meter before and after dosing.

Bleeding and segregation

Symptom: water film on the surface, aggregate settling. A water-retaining agent thickens the paste and holds water in place. Combine with correct sand grading; admixtures do not fix a badly graded mix.

Slump loss on the way to site

Symptom: mix loses workability before discharge. See our hot-weather article — a retarder and water-retaining combination is the standard fix.

Set time problems

Too fast in summer or too slow in winter: retarder extends set, early-strength agent and accelerator pull it back. Anti-freeze keeps strength gain alive below 5℃.

Corrosion or cracking concerns

For marine or de-icing salt exposure use a corrosion inhibitor; for restraint cracking and long elements, a shrinkage-reducing agent lowers drying shrinkage risk.

Browse the full product range, or describe your symptom in the sample request and we will send a matching grade with COA.