Unlike wood , insulation , and other construction materials , concrete does n’t burn . Modern civilization has practically built its substructure on it , from stairs to floors to agency tower . While not bursting into flaming is a good matter , concrete does have vulnerability — exposed to high temperature , it can set off like a handbag of microwaved popcorn . And scientist are get better at understanding why .
A recentpaperpublished in the journalCement and Concrete Researchoffered some insight into this unusual phenomenon . Researchers at Empa , the Swiss Federal Laboratories for Materials Science and Technology ; the University of Grenoble , and Institut Laue - Langevin direct an experimentation using engine block of concrete , which typically dwell of cement , sand , water , and other additives to increase strength or reduce permeableness . Heated to 1112 ° F , portions of the block exploded .
Using neutron imaging , researcher were able to visualize the accumulation of urine as the occlusion hot up up .
The principle behind it is largely thesameas popping popcorn kernels . In both instance , heated water vaporizes and becomes cornered . With nowhere to go , the built - up push is released , with the concrete becoming pressurized and breaking apart .
Part of the reason the vaporization becomes trapped is because water moves by from the heat reservoir — say , a ardor in an interior room — and toward the cool portion of the concrete . In doing so , the wateractsas a moisture barrier , preventing vapor from come through pores . in high spirits - performance concrete , which is often used in commercial-grade applications , has few pores , which makes the pressure from the evaporation more concentrated . The water in the mix can wrick to evaporation when temperatures reach 392 ° fluorine .
Why is realize this process important ? By exploring how and why concrete can break , additives can be developed to reduce or eliminate the force . The result will be secure , more fire - resistant buildings .
[ h / tLive Science ]
