Lightweight Aggregate Plays a Key Role in Pier Expansion

To expand Port Canaveral’s Cruise Terminal 3 (CT-3) in Florida, the project’s engineers needed something akin to a miracle – a cost-effective way to create structurally secure land where there was only ocean. To solve the technical constraints of the rebuild, the engineers turned to a lightweight geotechnical fill made from a rotary kiln-produced expanded shale, clay, and slate (ESCS). The unique physical properties of ESCS lightweight aggregate reduced applied vertical stresses and lessened the lateral force acting on the steel bulkhead wall system. In addition, the decreased loading on the structure allowed the design team to reduce the gauge and diameter required for the supporting pipe piles in the steel bulkhead wall system.

Penn Station’s East End Gateway

At the corner of Seventh Avenue and 33^rd Street, the East End Gateway provides a new direct connection from the street to Penn Station. This 40-foot-tall steel and glass canopy brings natural light to the Long Island Rail Road concourses below for the first time since the 1960s. Passengers arriving in New York City through the gateway are welcomed by the Empire State Building aligned directly in view. An innovative design and efficient construction allowed this monumental entrance to take on a life of its own above the busiest train station in the Western Hemisphere.

Pre-Construction Planning Leads to Significant Cost Savings

As part of an ongoing campus improvement program, the University of Florida and the University of Florida Police Department in Gainesville, Florida, recently commissioned their new Public Safety Building (PSB) located in the heart of the campus. The 50,792-square-foot three-story PSB consists of concrete tilt-up wall panels for the exterior and is supported by structural steel on the interior. The entire scope of the project also included a 6,931-square-foot renovation of the adjacent existing Centrex Building, which houses the University’s Emergency Management staff and emergency operations dispatch center.

The Mid-Manhattan Library Expansion

The New York Public Library (NYPL) system has served New York City since 1895, providing, as noted on its website, “free books, information, ideas, and education for all New Yorkers.” While many people may picture the grand marble façade and imposing lions of the Stephen A. Schwarzman Building (SASB) at Bryant Park (famously featured in Ghostbusters, among other movies and pop culture), SASB has been solely a research library since 1970. In that year, the circulating division of the branch, the part of the library that allows checking out books and materials, moved across the street to the upper floors of the Arnold Constable & Co. department store. This new branch was named the Mid-Manhattan Library.

Red Rocks Amphitheater is considered one of the world’s premier concert venues. Located in Morrison, Colorado, the open-air concept was constructed between a series of sandstone rock formations, creating a natural amphitheater with some of the best acoustics and visuals in the world. When the amphitheater first opened in 1941, the stage was uncovered and exposed to rain and snow, which could arrive at a moment’s notice traveling over Colorado’s Rocky Mountain Front Range. The stage remained uncovered until 1989, when a steel space frame was constructed out of small diameter pipe sections. For 30 years, the original stage roof was functional to shelter performers from the elements. Still, over time, the roof was deemed structurally insufficient due to rigging issues inherent to its design and increased rigging demands as shows became larger from a production standpoint. Therefore, the facility owner and the City and County of Denver asked for the complete removal of the existing roof structure and a replacement structure with an increased rigging capacity, which was safer to use and complemented the surrounding setting.

Cast iron columns, commonly used in building construction in the 1800s and early 1900s, possess low tensile capacities and require special attention to detail in building alterations. 315 Hudson Street is a ten-story cast iron column building undergoing such alteration in New York City. Extensive renovations to the building included lowering a portion of the ground floor structure, transferring two off-grid columns at the ground floor via transfer beams at the second floor, and reinforcing columns for new rooftop loads. Each endeavor required novel detailing to brace, support, and reinforce the cast iron columns in a manner that limited tension on the cross-section.

Nestled into a hillside of ponderosa pines with views of Humphrey’s Peak, the High-Performance training facility attracts top student-athletes to Northern Arizona University. DLR Group delivered a 65,000 square-foot, three-story, state-of-the-art High-Performance Center with a 10,000 square-foot weight room, sports medicine spaces, academic center, practice basketball courts, team meeting rooms, locker rooms, and a hall of fame. The facility also has an iconic team auditorium on the third level, with unobstructed views of the 12,600-foot Humphrey’s Peak and the San Francisco Range (Figure 1). The unique spaces and environment provided structural challenges and opportunities for creative design.

Boston University Center for Computing & Data Sciences

How do you build a 19-story, 305-foot-tall tower with 25-foot cantilever volumes offsetting in a counter-clockwise arrangement every two to three stories around the perimeter? Early discussions with Boston University, the design team of KPMB Architects, structural engineering firms Entuitive and LeMessurier, and construction manager Suffolk Construction identified the means and methods of erection as critical to the success of the Boston University’s Center for Computing & Data Sciences Building. Design-Assist, starting after the submission of Schematic Design, was utilized to identify the temporary erection procedures required to construct the tower. Steel fabricator, Canatal Industries, erector Prime Steel Erecting, and their engineer Simon Design Engineering were engaged to partner in the Design-Assist process with the design team.

A Case Study

Reimagining the iconic Sixth Street Viaduct over the Los Angeles River began with an exhaustive design competition some 10 years ago. By the project’s end this summer, HNTB’s collaborative design approach will have unified and optimized the architecture of a new viaduct while creating a decidedly unique structure in both form and function.

Solution: Heat Straightening

The Lava Fire, one of the largest wildfires to scorch California in 2021, burned over 26,000 acres and prompted evacuations of at least 8,000 residents. Sparked by a lightning strike, the fire burned for just over two months around the wooded slopes of Mt. Shasta. The extensive fire heavily damaged multiple structures, including Union Pacific Railroad’s Dry Canyon Bridge and nine miles of track near Weed, California.