Breathe easy, Eagles fans.

When the Birds soar next season, Eagles officials promise the bounce in your step will come from pure jubilation, not shaky exit ramps.

The Eagles plan to buttress two quiver-prone ramps at Lincoln Financial Field before the team's opening game.

In a report released yesterday, an engineer hired by the Eagles deemed the ramps safe but recommended fortifying both structures with steel braces to reduce motion. Eagles spokeswoman Bonnie Grant said the team intends to cover all construction costs, although they had to determine the price.

Initially, the Eagles planned to shore up just one ramp - on the northeast side of the stadium - after fans complained of a scary swaying sensation while exiting the Oct. 8 Eagles-Cowboys game.

Last week, city and Eagles officials asked engineers to reinspect all three stadium ramps after fans reported a dramatic rocking on the southwest ramp while leaving the Jan. 7 Eagles-Giants playoff game. There were no complaints about a third ramp on the southeast side, Eagles officials said.

A visual survey of the concrete and steel ramps found no "damage, excessive strains, overstress, or displacements," said Kimball J. Beasley, the engineer hired by the Eagles.

Beasley of Wiss, Janney, Elstner Associates, in South Jersey said the swaying was normal.

"When people move in mass along the ramp, they do not have room to walk freely and they tend to fall into step with the person ahead of them," Beasley wrote in his Jan. 15 report.

"In this situation, the entire crowd tends to create a harmonic lateral driving force."

Still, Beasley suggested adding steel frames to stiffen the northeast and southwest ramps. Both are free-standing structures that jut out about 120 feet from the stadium. Beasley's report said the ramp design was up to code.

But Steven Kiss, a Huntington Valley engineer, said he took one look at the ramps and instantly knew what was wrong.

"Ask any two-year engineering student and he'll tell you in two minutes," he said.

Kiss said the architect who designed the $512 million stadium failed to include stabilizing steel beams at the end of both ramps. He said the missing beams will cost roughly $500,000 to add.

David Perri, acting commissioner of the Department of Licenses & Inspections, said city code does not require architects to consider harmonic vibrations caused by crowds when designing ramps.

"The design met the code and therefore, we were satisfied and we were able to issue permits for construction," Perri said last night. "We can't arbitrarily impose standards that aren't part of the law. I can't say, 'Jeez, why don't you throw in a few extra braces on there?' " *