Visible on the skyline was Oscar Niemeyer’s sinuous residential high rise, the Edificio Copan. “It’s not the right angle that attracts me, nor the straight line, hard, inflexible,” Niemeyer once said. “What attracts me is the free and sensual curve — the curve that I find in the mountains of my country.”

Once all the strips were woven on the roadway — combining weaving principles with a fivefold symmetry pattern typical of Islamic geometry — the students moved swiftly, lifting the spray of bamboo and bending down the verticals. The dome popped into shape nicely, as Mr. Solly had predicted. “James deserves all the credit,” said Ms. Martin. Still, she told the students, “the computer is not your only tool. There’s a lot of information in the paper model.”

The enterprise drew a crowd, although the police, cruising by on motorbikes, hardly took notice. Felipe Rodrigues, an architect and a member of the Parque Minhocão Association , who was walking a full lap of the freeway while listening to NPR , stopped by to discuss the complexity of the space. “It’s alchemy,” he said: precious public space, in a city where shopping malls are known as the “Paulista beach.”

“The park already exists,” he said. “It’s already here. The park is the people who use it. I don’t see it anymore as an elevated highway. This is a platform for activities on which anything can happen.”

For the remainder of the week, the students assembled in design teams and envisaged their own structures for the park. One team went for a decorative, 50-foot Möbius loop . Another produced a rolling swoosh that became an irresistible tunnel for skateboarders when installed on the Minhocão during the workshop’s final day.