While the ongoing terminal core renovation (TCore) is the largest redevelopment project happening at the Portland International Airport (PDX), the Port of Portland (Port) has also been hard at work with the ever-present task of maintaining airfield pavement. In 2019, they hired Century West Engineering Corporation (Century West) for the Taxiway T Rehabilitation and Concourse B Apron Improvements project. This project had many components including: pavement rehabilitation for Taxiway T, shoulder widening for Taxiway T and Taxiway B, apron improvements at the Concourse B ramp, and stormwater and electrical upgrades throughout the project area.
Regular pavement monitoring completed by the Port’s pavement maintenance program revealed the need for the Taxiway T portion of the project. Geotechnical evaluations, including falling weight deflectometer (FWD) and subsurface sample tests, showed that the Taxiway T pavement was experiencing fatigue and subsurface stripping, which is a loss of bond between aggregates and asphalt. As the stripping issue did not extend to the bottom of the asphalt, a targeted mill and inlay approach was chosen over a costly full depth reconstruction. Most of the taxiway needed only a four-inch inlay to address and remove surface raveling, though some areas required milling down to 12 inches to mitigate stripping. One section of pavement—the intersection of Taxiway T and Taxiway B—did require full depth pavement reconstruction due to a combination of pavement distress and subgrade failures. Century West also provided design to widen the shoulders of both taxiways to meet Federal Aviation Administration (FAA) standards.
The TCore project includes the removal of Concourse A, and therefore requires other concourses to expand their operational capacity. At Concourse B, Century West extended the concrete apron area for Gates B1 to B4, as well as added new concrete hardstands for the remaining B gates. This expansion accommodates additional large jets for remain overnight parking, including B737s and A321s. As part of the layout for the remain overnight parking, the Century West team completed AviPLAN models and modeled ground surface equipment layouts to make sure there was enough space to tow planes in and out of parking position. Improvements at Concourse B also included a three-inch mill and inlay of the entire asphalt section to increase its lifespan.
Storm system improvements included the replacement of 2,500 linear feet (LF) of an existing 24-inch east/west storm main and approximately 900 LF of a 36-inch north/south storm main within the Concourse B Apron and Taxiway T Rehabilitation area. Additional stormwater improvements included the reconfiguration and replacement of existing storm laterals and catch basins within the project area to extend the life of the storm system and correct existing deficiencies. The previous system was not built all at one time, and Century West’s design efforts brought cohesion to a previously pieced together system without the need to add additional stormwater treatment capacity. Electrical improvements included adjustments and replacements of the existing lighting system and power/communication vaults within the project area.
Completed construction at Taxiway T.
Significant construction phasing planning before the project broke ground resulted in few surprises or challenges during actual construction. The Port team collaborated with the airlines and other stakeholders during design to ensure the project was phased appropriately around the TCore improvements to keep PDX operational. Closing areas for an extended period was not an option, so the project was separated into two construction seasons: much of the project was completed in 2020, but the concrete apron expansion was delayed until 2021 due to ongoing construction at the Concourse B building. The total construction cost of all improvements was approximately $9M.
While TCore improvements are still ongoing, Taxiway T, Taxiway B, and the remain overnight parking area at Concourse B are all in use.