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    The Texas Children's Hospital project in Houston demonstrates how BIM can be an important part of a concrete structure's design and construction. Engineers from Coreslab Structures used a specially designed BIM software program from Tekla to coordinate the architectural precast cladding project in Tekla Structures. This project was completed from start to finish using only Tekla Structures software and its extended application. Design engineers scanned information about the the cast-in-place structure and supplied the data to Coreslab in a 3-D CAD file. The precaster used the model as a reference to spot errors before shipping their panels. The precaster also used a software feature to track the erection sequences.

This SDC initiative to drive a more widespread use of BIM in the concrete industry will support ACI's newly formed technical committee 131, Building Information Modeling of Concrete Structures. Peter Carrato, who coordinated the BIM discussion during the SDC session, is its chairman. ACI 131's first meeting was held at the ACI Fall 2009 Convention. It will meet again in March at the ACI Spring 2010 Convention in Chicago.

SDC's supporting efforts include two steps occurring in the first half of 2010. In January, SDC conducted telephone interviews on the use and importance of BIM. These interviews will be combined with SDC's BIM survey conducted in mid-2009. The results will form the basis for a white paper published in the first quarter of this year.

SDC members can see the survey results and discuss the whitepaper on May 5-6. The meeting will be held in conjunction with SDC Session #27 in Kansas City, Mo., as part of Phase 1 of SDC's BIM initiative.

While the SDC efforts are important, the concrete industry faces a larger task: countering the nearly decade-long influence the steel industry already has on BIM. The American Institute of Steel Construction (AISC) in 1999 launched and funded a multi-year initiative to promote Electronic Data Interchange (EDI) throughout the structural steel industry. Modeled on an earlier European initiative, the steel industry has used BIM as a selling point to show how its material interacts in all BIM functions such as interference/clash detection, detailing, fabrication, erection, procurement, construction planning, and scheduling.

But that's not to say producers haven't been involved in BIM. To retain a portion of the structural BIM design market, several precast producers developed BIM standards in 2001. They formed the Precast Concrete Software Consortium (PCSC) to fully integrate its members' engineering, production, and construction operations through adopting advanced information technologies.

A specification of the requirements for a Precast Modeling Platform was completed late in 2001. The next year, the PCSC solicited and evaluated offers from software companies, CAD vendors, and precast application vendors to provide the platform. Tekla Inc. was selected to develop the software.

It took about four years to prepare the final software specification, a joint effort of Tekla and the PCSC supported by a team at Georgia Tech led by Charles Eastman, with Rafael Sack and Ghang Lee. The first release of the full platform came in 2004. Various North American precast software application providers (notably LEAP software) committed to adapt their applications to function directly within the Xengineer Precast Platform.

By 2005, PCSC's effort to develop a knowledge-rich 3-D CAD system for the North American precast concrete industry was completed. PCSC company executives accepted the precast concrete extensions to Tekla Structures. The PCSC expects to increase productivity and quality using this tool and significantly increase concrete's market share in commercial design.

Tekla used the information to develop a Structure Precast Concrete package to create and maintain various types of predefined and user-defined precast components, connections, reinforcement, and pretensioning strands automatically, depending on the parametric modeling technology.

The new module includes other features specific to precast concrete structures, such as shortening, cambering, and warping of double tees, hollowcore, stairwells, and architectural panels. Drawings and reports can be automatically generated based on customized drawing and report templates.

And this year, the Georgia Tech Research Corp. will deliver a Precast Concrete National BIM Standard. Eastman and Sack are developing the document to submit to the National BIM Standard Committee. The standard deals with the broad domain of precast buildings, including parameters for stemmed deck members, flat deck members, beams, columns, load-bearing walls, spandrels, piles, and architectural facades.