Scientist have added a special polymer to self-compacting concrete mix that they claim better equips the concrete to withstand high temperatures and maintain the integrity of the structure.
Polypropylene fiber added to normal vibrated concrete mixes helps prevent pressure from building inside concrete exposed to high temperatures. However, adding these fibers to self-compacting concrete impacts its ability to self-compact.
Scientist at the Swiss Federal Laboratories for Materials Science and Technology (EMPA) have created a series of thin concrete walls mixed with some polypropylene fibers containing a synthetic material known as super absorbing polymer (SAP). The SAP fibers are soaked with water beforehand. Then as the concrete sets the water is drawn out through the cement matrix causing the SAP to shrink and leave behind hollow spaces inside the concrete.
EMPA test showed SAP concrete exposed to temperatures of up to 1,852° Fahrenheit for 90 minutes exhibited some minor cracking but no severe chipping and flaking.
