Why foam concrete cement have stability requirements?

Foam cement used in concrete can not be arbitrarily blending different levels, in addition to the production of foam concrete for cement stability is also required, mainly as follows:

Cement stability refers to whether the volume change even after hardening cement, cement stability failure, foam concrete cracks, so that the project was dangerous, so the production of cement foam concrete must be tested to prove that you can use a good stability after. Otherwise, it will bring huge adverse effect!
The storage time is not too long cement, cement particles and water vapor in the air, carbon dioxide play a role (a hydration reaction) the ability to reduce the cement. Damp serious, all form lumps, not be used. Significantly decreased after the wet strength of the cement, the setting time will be extended. This will affect the final results of foam concrete, please choose carefully!