Why is it that during concreting, aluminum materials is not advisable to convey concrete or use as forms in contact with concrete?

Aluminum reacts with the alkalis (OH) found in portland cement concrete. When these two chemicals are combined, the reaction produces hydrogen gas. This is why, when the reaction occurs in wet concrete, you will  notice tiny bubbles coming to the surface of a slab.

A significant corrosion of aluminum embedded in concrete can occur. The corrosion can cause expansion of the concrete and subsequent cracking of hardened concrete.

Aluminum reacts with portland cement concrete. The reaction produces hydrogen gas which cause mix to expand.

BECAUSE ALUMINUM WILL EASILY ABSORB HEAT, CONCRETE MIX WILL NOT MEET THE DRYING TIME PERIOD, THEREFORE THE CONCRETE WILL RESULT TO LACK OF STRENGTH.