One Tribe Place

At various locations, persistent water infiltration had resulted in significant damage to structural slabs, reinforcing steel, post-tensioning cables, and electrical conduit. The investigation uncovered poorly constructed flashings, membrane failures, and inadequate drainage, corroded reinforcing steel, and failed post-tensioning tendons.

As a part of the overall structural and waterproofing repair program, WDP developed demolition and repair documents to install new masonry flashings, plaza deck waterproofing, and below grade waterproofing to address water infiltration into the garage levels as well as to repair structural concrete, reinforcing steel, post-tensioning tendons, and anchorages.

At the courtyard, the existing brick pavers, concrete topping slab, and planter were removed to facilitate an evaluation of the post-tensioned slab and make necessary repairs. Following structural repairs, the new waterproofing membrane was installed with new flashings to correctly tie into the perimeter masonry. A topping slab and brick paver system was then installed, including the addition of new two-stage drains. Similarly, the tile pavers at the pool deck were removed to allow for the installation of a new waterproofing membrane and proper flashings at the intersections with adjacent masonry walls. The pool itself was abandoned, requiring that WDP design a new waterproof structure to occupy the pool space. On the building exterior, subgrade waterproofing was detailed to address the exterior concrete walls and halt water infiltration into the garage.

The concrete slabs of the parking structures and the now converted dormitory rooms were surveyed. A condition assessment was performed to evaluate the damages of the PT tendons, to examine the as-built conditions of the structure, to find the cause of the damages, and to develop the repair design. The original construction drawings were not available, and the project required development of the base drawings including general concrete floor construction, locations of construction joints, and PT tendon layout in plan. Non-destructive testing was used to locate the PT tendons and their profile, exploratory openings were made to examine the conditions of the PT tendons, samples were taken to examine the material properties of the concrete and PT tendons, structural analyses were performed to evaluate the existing structure, and a repair design was developed to remediate the conditions. Various repair techniques were applied including concrete repair, PT tendon replacement, tendon splicing, and new anchorage placement.

WDP also provided construction support services to the University throughout the renovations, including regular site visits and prompt responses to Contractor RFI’s and unforeseen conditions. These renovations were completed in 2020. WDP is currently contracted to perform a building enclosure investigation on the former hotel’s addition to address issues related to air and water infiltration.

WDP received the 2022 “Outstanding Award in Structural Renovation under $25M” from the Structural Engineers Association of Metropolitan Washington (SEA-MW) for services performed work on the One Tribe Place Post-Tensioned Concrete Slab Repair project.

Water infiltration has plagued this structure for years, leading to extensive structural damage. WDP’s thorough investigation was able to identify multiple sources of infiltration that were not properly addressed during previous attempts by others. The execution of WDP’s repair design has finally halted this excessive water infiltration through various components of the structure. With water infiltration finally under control, the structural post-tensioned concrete repairs can be confidently performed without threat of future damage. WDP’s engagement with the Owner and Contractors throughout the repair process resulted in quick reaction to unknowns and the ability to maintain the project schedule.