CHICAGO — A dramatic crack in a steel beam underneath Lake Shore Drive means northbound lanes will be closed at Randolph during the evening commute Monday.

Drivers are being diverted off the Drive and the ramp from eastbound Randolph Street onto northbound Lake Shore Drive is also closed for the time being, according to a CDOT news release. Southbound lanes were open and operating as usual.

Look closely two beams are cracked pic.twitter.com/sWpxkCI8pG — Roseanne Tellez (@RoseanneTellez) February 11, 2019

Crews are trying to put up a shoring tower under the viaduct structure, but it was not immediately clear when the closure will end, according to CDOT.

“The road will be closed through Monday’s PM rush and possibly longer,” according to the agency. “CDOT will provide updates as soon as they are available.”

No one has been injured and no cars have been reported damaged, according to CDOT.

BAD-Here’s why N bound .

LSD shut down at Grand

Two steel beams completely cracked

⁦@cbschicago⁩ pic.twitter.com/0R9Q8zuYJb — Roseanne Tellez (@RoseanneTellez) February 11, 2019