award winners and outstanding projects Spotlight Bellezza e funzione Design of New Government Seat Combines Beauty & Function By Aine Brazil, P.E., LEED AP

Thornton Tomasetti provided structural design services through design development for the Lombardia Regional Government’s new headquarters complex in , , a project selected as one of the winners for the NCSEA 2011 Excellence in Structural Engineering Awards in the International Structures Over $100 Million category.

n 2004, an international competi- were the curved building shapes and floor-to- tion was held for the design of the floor heights. ® Regional Government’s new Construction began in December of 2006 seat and civic square in Milan, Italy. and was completed in March 2011. The com- ILocated in northwestern Italy, Lombardia pleted government buildings include general is the most populous region in Italy and assembly spaces, offices and areas for social its capital, Milan, is one of Italy’s most functions and public debates. densely populated areas. The competition A large enclosedCopyright piazza with a curved glass to design the new government seat and civic roof at the center of the site references Milan’s square required entrants to consider a visible Galleria, and links to two secondary open symbolic and functional presence in their spaces and a linear landscaped spine. The designs. Another factor that affected the site piazza roof is covered by a tubular lamel- was the proximity to the Tower, an lar (skewed grid) structure spanning 459 existing icon in the local landscape. feet by 148 feet (140 meters by 45 meters) The final Pei Cobb Freed and Partners and is clad in an extremely light, innovative Palazzo Lombardia. Courtesy of Simon Hsu. Architects LLP design was chosen from 10 Ethylene Tetraflouroethylene pillow mem- finalists who were selected from a larger group brane system. The rim of the “eye” shaped service and stair core is enclosed by cast-in- of 98 applicants. Their winning design was roof structure is supported along the edges of situ concrete shear walls to create the lateral inspired by the region’s interweaving moun- the magazinepodium structures with slide bearings that system for the building, to resist both wind tain peaks, rivers and valleys.S The open T spaces Raccommodate U building C movement T at expan-Uand earthquakeR E forces. created by the curved forms of the buildings sion joints. The enclosure of the building is a The curvilinear form of the building makes encourage the community to gather, rein- highly innovative and efficient “climate wall” a cast-in-situ concrete system an appropriate forcing themes of engagement and social double layered glass curtainwall. and cost-effective structural solution for both interaction. Thornton Tomasetti provided The project also includes an open roof the low-rise buildings and the tower. Concrete structural design services through design garden with trees and landscaping, enclosed is the local material of choice, and Italian development for the project by an approximately 50-foot (15-meter) tall building codes required office spaces to have Sited in the greater Garibaldi-Repubblica wall of glass supported by vertical cantilevered access to direct light. urban enhancement area, close to the heart tube steel vierendeel trusses with no overhead Flat plate construction was possible of the city, its scale relates to the surround- beams. Grand entrances to the piazza are cre- because of the narrow building width, which ing neighborhood, while the tower speaks to ated by open double height ground floor areas addressed this constraint and eliminated the the Pirelli building and the city. Key design and multiple column transfers. long spans that can make concrete an unsuit- principles were: to create an urban passage The project is divided above grade into six able material. The low-rise buildings follow a that invites entry and is a significant destina- building structures separated by expansion repetitive form, permitting multiple reuse of tion; design a sequence of engaging spaces joints that accommodate thermal expansion the formwork. Column formwork economy that promote social interaction; and add an and contraction. The maximum length of was provided by using uniform sizing and emblematic vertical element that contributes these structural units is approximately 361 standard floor-to-floor heights. Once the proj- to Milan’s skyline. feet (110 meters). Although in Italy expan- ect was passed on to the Italian design-build This high-profile headquarters includes five sion joints are commonly spaced more closely contractor Consorzio Torre, the construc- nine-story wavelike buildings that total 1.05 than 328 feet (100 meters), the architectural tion team opted to substitute some of the million square feet (98,000 square meters), layout and the arrangement of the structural cast-in-situ elements with precast elements a 43-story tower that is 405,000 square feet elements in these buildings facilitate the larger in an effort to accelerate the schedule. This (37,000 square meters), three parking/stor- joint spacing. was most prevalent with the columns and flat age levels below grade and a plaza with an The 525-foot (160-meter), 43-story tower plate slabs in the gravity system.▪ irregular footprint of 856 feet by 607 feet structure has an efficient concrete form even (261 meters by 185 meters). The major deter- with the curves presented, which made Aine Brazil, P.E., LEED AP is Vice mining factors in the choice of structural finding economical solutions to structural Chairman of Thornton Tomasetti. materials and structural system for the project requirements possible. The major elevator,

STRUCTURE magazine67 April 2012