ERDC modular shelters safeguard U.S. Embassies, State Department employees

VICKSBURG, Miss. - As a research civil engineer with the U.S. Army Engineer Research and Development Center’s (ERDC) Geotechnical and Structures Laboratory (GSL), Justin Roberts began exploring ways to use his blast mitigation expertise in protecting unique facilities from large scale explosive testing and his past research experience with structural responses to dynamic loading to develop a new approach in keeping personnel safe.

His answer was the Modular Anti-Ballistic, Blast and Forced Entry Resistant Shelter, or MABFERS, which was awarded a patent in October 2019. The MABFERS serves as personnel protection in high-threat locations abroad and is used in various U.S. Department of State (DOS) locales.

Shelters for Embassies’ personnel, others

“When remodeling of U.S. Embassies are underway, the displaced personnel need a safe place to temporarily move and continue their work,” said Roberts. “The MABFERS can be installed quickly and offer the space needed with a high level of protection so its occupants can be safe and focus on their missions.”

“This system is deployed to high-threat locations to protect its occupants against car bombs, rocket and mortars, ballistic attacks and angry mobs,” he added. “It offers a validated protective solution for diplomatic personnel to operate from while providing exceptionally high levels of protection.”

Effectively, MABFERS grew out of another GSL collaboration effort, the Hardened Alternative Trailer System (HATS). “MABFERS is a continuation-in-part of HATS,” said Roberts. “The MABFERS expands the HATS technology into a structural building system using 40 foot International Organization for Standardization (ISO) freight container compatible components.”

Using components from ISO containers for compatibility with intermodal transportation allows for multiple modes or carriers to transport freight from the shipper to the final destination.

“Two basic component types — an end unit and a middle unit — provide the building blocks for assembling one or two story structures that are 40 feet in length by infinite widths in eight-foot increments,” Roberts added.

Advantages of HATS expansion

“The HATS became a go-to structural solution for the State Department,” said Roberts. “The ease of logistics, installation and the high levels of protection offered for the price not only fulfilled their requirement for high-threat locations, but exceeded their expectations. DOS quickly realized the endless possibilities for this technology if expanded to provide larger unobstructed spaces. Aside from one or two personnel housing and office spaces, the expansion of this technology could allow conference rooms, dining halls and a myriad of other functional uses.”

Roberts said, the idea was a derivative of the HATS technology which incorporates heavy steel protective armor schemes into ISO shipping industry framework for individual protective spaces.

“The two-story option would allow the DOS to double their protected space on limited real estate sites while staying within the ‘temporary structure’ status,” he said. “The construction time for a temporary structure is significantly less than conventional methods due to the less restrictive code compliance and permitting. This would allow DOS to get the protection they need at a location very quickly.”

The GSL and DOS team began conceptual drawings for MABFERS in 2015, followed by two years of experiments and final product development in late 2018.

 Invention process, contributors

“The idea was to mesh HATS technology with the ISO shipping industry framework to produce logistically friendly building components.” said Roberts. “The design began with basic conceptual sketches with fit and functionality in mind. Once we conceived the building components that satisfied the design intent, we began to consider the next level of detail. We performed basic structural analysis using static loads to determine the minimum sized structural elements.”

“Next, we performed a dynamic analysis using a specific blast threat. This was more complex and took several iterations to arrive at the structural elements that would perform within our damage criteria. Once satisfied with the design, we began the blast experiments to validate the design. Like most research and development efforts, this too, was an iterative process. We conducted several experiments where the main components performed well but the global structure did not perform satisfactorily due to connection issues. We enlisted the help of our computational modelers to model the connections and figure out what was going on during the extreme loading event. With the additions made from their input, we were able to experimentally validate the system,” Roberts said.

With its rich research history dating back to the 1930s, GSL offered the team facilities both in Vicksburg, Mississippi, and Leesville, Louisiana, for the design and prototyping, as well as, access to the skilled crafts people at ERDC’s Directorate of Public Works (DPW).

“Our DPW shops played a huge role in fabricating the MABFERS components that were tested,” said Roberts. “We employed six men for the better part of a year for this effort. The experimentation was carried out at the ERDC Test Facility at Fort Polk in Louisiana.”

“Our challenge was to develop a shelter for larger unobstructed spaces to meet various functional requirements with a high level of inherent protection,” he continued. “This system will be used at different locations around the world. There are already some projects underway at undisclosed locations where the MABFERS will be placed.”

The MABFERS patent team includes fellow GSL Survivability Engineering Branch research civil engineer John M. Hoemann and DOS Blast Effects and Special Project Initiatives program manager Craig R. Ackerman with the State Department’s Diplomatic Security Physical Security Division.

The team will be recognized later this year with a plaque presentation ceremony by leaders from ERDC’s Office of Research and Technology Transfer which processes patent applications for the center.