Aluminium Posts In Concrete

Second if the aluminum is coupled with any ferrous metals galvanic corrosion will occur also.

Aluminium posts in concrete.

Ironcraft orleans 2 in x 2 in w x 6 ft h black aluminum line fence post. The ph of fresh mortar ranges from 12 to 13. A number of cases have been reported in which excessive corrosion of aluminum conduits has resulted in cracking and spalling of the concrete in which it was embedded. Water most likely settles between the post and the setting cement.

But serious consequences can arise in situations of long term contact. And in areas subject to frost heaves this can be an invitation to trouble down the road. There is no sealant at the base of the post where it meets the bonsal grout. Aluminum in contact with plain concrete can corrode and the situation is worse if the concrete contains calcium chloride as an admixture or if the aluminum is in contact with a dissimilar metal.

For steel or aluminium posts please ensure that your posts are sealed according to the manufacturers recommendations to prevent corrosion occurring. Archive view return to standard view. Novices anticipate no problem in setting fence posts in such holes then filling the holes up with concrete. Aluminium posts with quick set concrete.

Posted 2012 oct 13 5 55 pm aest. Aluminum powder is added to the concrete and the reaction fills the concrete with gas bubbles. This finish is a baked polyester enamel coating which is manufactured to meet or exceed aama specification 603 8. Instead of concrete consider something else like gravel there s also an expanding foam similar to great stuff that s rated for ground contact and sold specifically for setting fence posts.

In fresh concrete aluminum reacts principally with alkali hydroxides from cement. The result is a v shaped hole. Rapid set concrete specially formulated to harden rapidly so you can complete a job faster. The corrosion can cause expansion of the concrete and subsequent cracking of hardened concrete.

But when you fill those v shaped holes with concrete you end up with v shaped hunks of concrete. In cases of corrosion where the concrete cover was too thick to result in concrete failure the conduit collapsed inwardly.