TxDOT to repair big bump on SH 45 in Round Rock

What started out as a small bump in the road is now a road hazard. 

Warning signs about the big bump on SH-45 are now up with vehicles heading east and west bouncing off the tollway between MoPac and I-35.

"You know how you ride a bus, back in high school, and you hit that speed bump, I almost hit my head, and I’m 5'5," said Round Rock barber Marcos Morales.

For Morales, SH-45 is a shortcut to work that he may now have to avoid.

"There’s always alternatives and honestly like as long as they get it done that’s all that matters, so I don’t care to take a longer route," he said.

The problem area is where the road connects to the CR 172 overpass, which started buckling a few years ago but started getting larger during the summer. Now that the bump has become a potential hazard for drivers, TxDOT is working on a repair plan.

Roads are designed to expand, but can buckle under extreme heat. Essentially the sections run out of elbow room. Civil engineers call it a blow-up.

"We have to accommodate these movements of expansion and contraction," said Dr. Tommy Nantung, an engineer with the Indiana Department of Transportation who studies blow-ups.

"We can see the tail tell signs of pavement is about to blow up because when you have movement on the slab like that, the sealant, the asphalt sealant in the joint will be squeezed up," he said.

Dr. Nantung provided FOX 7 Austin with images of different types of blow-ups. Repair work could be as easy as a patch or a total tear out. The real fight, he says, starts with keeping water out.

"California is very innovative, so in areas where they are susceptible to blow outs, they put foam in the joints," said Dr. Nantung.

Officials with TxDOT say a repair plan should be ready by next week. Work could start by the end of the month.