Anti-Terrorism & Force Protection
ANTI TERRORISM & FORCE PROTECTION (ATFP)
Physical security design for anti-terrorism can be economically incorporated into the design of a new facility or renovation project when done early. Many “Blast Specialist Engineers ” advertise that their involvement begins after 35% design and that they do not assume “Engineer of Record” (EOR) responsibilities. In most cases, consideration of physical security after 35% design is far too late. Physical security design needs to start during the site selection and programming stages to result in an efficient design.
The effects of explosives, the weapon of choice for terrorists, diminish exponentially with the stand-off distance between the Design Basis Threat (DBT) or bomb and the target or building. However, while increasing stand-off distance requires more land, decreasing the stand-off distance requires more extensive building hardening to achieve the same level of protection. A study of blast affects versus stand-off distance will result in an optimum stand-off distance where the desired level of protection can be achieved at the least cost. Additionally, a heavy and ductile building envelope can absorb bomb blast energy better than a light weight brittle one thus resulting in a more economically designed building envelope. By 35% design, not only has the site been selected, but many other design features such as the exterior wall construction has been decided on as well.
Other than low occupancy buildings, such as agricultural, temporary and minor storage facilities, Department of Defense (DoD) buildings that are three or more stories must be designed for progressive collapse (PC). For General Services Administration (GSA) Facility Security Level (FSL) I buildings (low occupancy storefront type of operations), no specific progressive collapse requirements need be met. GSA FSL II buildings (routine federal activities similar to commercial) must be constructed of inherently ductile materials, able to respond to load reversals, such as reinforced concrete and structural steel. GSA FSL III and IV buildings (law enforcement, courts and records) more than 3 stories must be designed for progressive collapse. All GSA FSL V buildings (mission critical such as the Pentagon or CIA Headquarters) regardless of height shall be designed for PC. And virtually all new Veterans Affairs (VA) facilities shall be designed to prevent progressive collapse. Therefore, since the structural system is often selected near the project kickoff or Design Charrette, progressive collapse design needs to be considered at the onset of project design.
And lastly, other design discipline considerations such as a controlled perimeter, vehicle access and approaches to the building and the location of critical infrastructure and air intakes need to also be considered at the onset of design to be economically incorporated into the building design.
Therefore, your “Blast Specialist” should routinely act as “Engineer of Record” for building designs so they understand the importance of this early involvement and are familiar with the fine points of building design. They should also have experience and feel comfortable consulting to other disciplines besides structural so they can offer useful constructive design input early in the design.
The IEI Advantage
Our core business at Innovative Engineering Inc. has always been acting as the structural Engineer of Record for buildings and other structures. We understand the importance of this early involvement in the design and are familiar with the fine points of building design including all disciplines, particularly related to protective design and routinely offer useful constructive design input early in the project design.
Over the last 20 years, we have developed an expertise in the area of physical security and anti-terrorism protective design including blast and progressive collapse design. Our experience includes both structural and physical security design and peer reviews for the federal government as well as the private sector. We routinely consult to other structural engineers and disciplines in the area of physical security and respect their client relationship. This combined experience fills the gap between theory and the practical and efficient incorporation of protective design into the built environment.