Executive Summary:

The S.T.E.P.S. Building in Bethlehem, PA sits on Lehigh University's campus. It is a mixed use facility consisting of laboratories, lecture halls, and faculty offices. The building is divided into two main wings which are bridged by a central atrium.

The existing structural system of the building consists of semi-rigid moment frames and full moment frames. It uses a composite floor as a rigid diaphragm to transfer lateral loads imposed on the façade to the beams and girders. The beams and girders then transfer these loads through their moment connections to a network of mainly W14 columns. The columns finally transfer the load into the soil through a combination of spread footings and mat foundations.

The structural depth consists of two major tasks. First, the floor system were checked against vibration control tolerances and redesigned. The building contains sensitive laboratory equipment which requires vibration tolerances on the floor. The existing floor did not meet the chosen design tolerance of 2000 micro-inches/second for moderate walking. The redesigned floor included reducing the beam tributary width from 10.67' to 7.11', an increased beam section, and a W24 girder instead of a W21.

Second, the semi-rigid wind clips will be replaced with braced framed and full moment connections. The controlling wind case was found, and forces were distributed assuming a rigid diaphragm and idealized k values. They were then applies to the connections, and all applicable limit states were examined. The moment frames resulted in full depth stiffeners and doubler plates for the column. A ½" gusset plate supports an HSS 4x4x1/2 eccentric brace in the eccentrically braced frame.

The two breadths are related to the electrical and construction management disciplines. The construction management breadth consists of a detailed construction sequence with crane positioning. The construction schedule runs the length of the project in detail, and a site layout describes where the crane can safely and effectively be placed. The electrical breadth provides a typical panelboard schedule, electrical capacity estimates, and details on emergency lighting and fire alarms.

In this thesis redesign, the following goals were set and achieved:

1. Analyze the existing floor system for vibration resistance with AISC Design Guide 11
2. Redesign the floor to allow for 400x microscopes at moderate walking speeds
3. Redesign the lateral system with full moment frames and braced frames
4. Design a typical moment connection in detail
5. Design a typical braced connection in detail
6. Create a construction schedule
7. Create a sitemap with crane positioning
8. Create a panelboard schedule and estimate electrical capacity