SAN JOAQUIN COUNTY COURTHOUSE

Technology’s Leading Role Various technologies utilized on the job

also have significantly contributed to the project’s efficiency and facilitated a smooth project flow. The team has used programs including Navisworks, Bluebeam, BIM 360, and Google Sketchup, and they even employed the use of a drone early on to map the project’s progress. Field crews have constant online access to the most current plans and drawings via iPads or iPhone apps. In addition, throughout the jobsite, key subcontractors sport modified tool boxes equipped with a large monitor or computer screen to enable instant access to the latest plans in a larger format version.

High Degree of 4D BIM Perhaps most notable on the technol-

ogy front is the design and construction team’s high level use of 4D Building Infor- mation Modeling (BIM). In addition to the usual modeling of mechanical and electri- cal components for clash detection and co- ordination, the team has also taken BIM to the “next level” by detailing various exte- rior components in the model such as cur- tainwall and exterior precast work among other things. The model additionally has been used for schedule coordination and even site logistics and planning. “I would say we resolved thousands

and thousands of clashes within this 340,000-sq.-ft. building during precon- struction,” Della Monica said. “Coordi- nating the embeds and the exterior skin with not only the structural trades, but also how they interface with some of the interiors was very valuable. We were able to modify some exterior framing, metal stud framing items that would have been an issue in the field, otherwise.” Added Della Monica, “We found some

vertical piping that went right up to the ex- terior wall that was in conflict with some of the precast components, but we were able to resolve a lot of that ahead of time in a virtual setting before it ever became an issue in the field.” 4D BIM coordination helped Turner

determine that two tower cranes would offer the best approach for managing con- struction challenges. Those included dif- ficult site logistics and a highly restricted material laydown and staging area due to the project’s location immediately adjacent to the existing facility and its downtown location. They

coordinated highly de- www.AGC-CA.org

Slated to be the tallest structure in San Joaquin County when complete, the project hit a key milestone this May when the structural steel building topped out just a year after groundbreaking. Photo courtesy Ron Chapman, Stockton Police Department Historical Archives

tailed schedule planning on a daily basis, down to 15-minute increments, to ensure maximum efficiency and use of the tower cranes. Other major challenges have in- cluded a shortage of skilled manpower, re- quiring Turner to work closely with local unions and subcontractors to successfully staff the job. The design and construction team

also used the 3D model to create a virtual mockup followed by a real, scaled mockup of one of the new building’s 18-in.-thick cast in place concrete walls, to iron out

myriad details and show subcontractors as they came on board, Della Monica said. “We were able to model that down to a fab- rication level detail, looking at every bar of rebar that went through it, how the form- work was going to interface and so forth,” he noted. “It proved to be pretty fruitful for everyone involved.”

Prefabrication Plays Key Role While the high level of BIM coordina-

tion has resolved potential conflicts in the field, it also has enabled a high degree of prefabrication on the job. That has deliv- ered further benefits, according to Turner project manager Brian Sauer. “As a result, the subcontractors saved so much time with manpower on the site, which has helped us achieve our schedule,” he said. Major prefabricated components in-

clude mechanical systems, exterior glaz- ing, electrical components, and bathroom assemblies. The courtrooms were all pre- fabricated in a shop in Quebec, Canada and then brought to the site to be reas- sembled in place. Ensuring quality control on the pre-

fabricated components is critical and re- quires hands-on management, Sauer said. “We’ve spent a lot of time traveling and managing that [prefabrication] process at the factories.” Competition for shop time from many other ongoing projects increases the need to closely manage the process, he added.

Rendering by NBBJ Architects Associated General Contractors of California 11