STRUCTURAL OPTION

SILVER SPRING GATEWAY
SILVER SPRING, MARYLAND

This is a student-generated Capstone Project e-Portfolio (CPEP) produced in conjunction with the AE Senior Thesis e-Studio.

Senior Thesis Final Report

Structural Depth

For the purposes of this thesis, JBG, hypothetically, acquired the lot surrounded by the Northwest sections of 9th Street to the East, 11th Street to the West, New York Ave to the North, and H Street to the South.  JBG will petition to alter the C-3-C zone to a C-4 zone to gain twenty to forty more feet in building height thus matching the surrounding buildings.  Altogether, this site can accommodate the same architectural layout as the Silver Spring Gateway; however, due to the high profile aspect of the clientele and proximity to government buildings, the structural design may need altered to resist possible terrorist or protestor attacks.  First, the locations exuding the most vulnerability to an attack need determined, such as, parking garage, entrance tunnel, exterior façade, etc.  Since the current design lends well to several unique scenarios, the structural elements within the existing system will be analyzed per each scenario and redesigned, if necessary, to mitigate the effects of an explosion and to prevent a progressive collapse in case a localized failure occurs. The structural anaylsis showed deficiencies in the ability of the existing structural system to prevent a progressive collaspe; however, using methods developed by GSA and the Department of Defense enabled the structure to be redesign to perform satisfactory in the event of a terrorist attack.

Breadth Studies

Along with the structural alterations, architectural changes will inevitably ensue.  In order to maintain as much of the architectural program as possible, the architectural layout may also need redesigned due to the structural enhancements.  In addition, the façade may need further attention due to possible historic guidelines and to resisting a street side explosion.  Consequently, the façade change requires focus on blast resistance, architectural and historic concerns, mechanical load and daylight effects, and different moisture control techniques. Most importantly, the site and landscape architecture will need redesigned to ultimately mitigate the attack to protect the structure and its inhabitants from harm.

The new site is exceptionally larger than the original which allows for more buffer or stand-off range between the street and the building. This buffer zone acts as a public and private plaza which adds to the outdoor atmosphere to the development. The access points are restricted by several different countermeasures for supreme safety of the tenants.

The facade did not need to be redesign due to surrounding architecture or for blast resistance purposes; rather, a minor change to increase the functionality of the wall assembly in thermal and moisture protection.

To view a PDF version of the Full Report, click here.

To view a PDF version of the Executive Summary, click here.

To view a PDF version of the Report only, click here.

To view a PDF version of the Appendices only, click here.