E. Alfred Picardi, the structural engineer for Chicago’s 1,136-ft-tall Aon Center, died on Aug. 14 in Virginia Beach, Va. He was 88. Picardi eventually became chief engineer at Chicago’s Skidmore, Owings & Merrill, where he had a hand in designing the city’s 1,128-ft-tall John Hancock Center. He left the firm in 1967 and went to Perkins & Will, where he designed Aon, the world’s fourth-tallest building when completed in 1973. Picardi developed a way to use the tubular structure’s V-shaped exterior columns as a container for its mechanical systems and adapted the oil firm’s cost and risk simulations to similar computer algorithms for construction estimating.