General Contractor: Bluebonnet Contractors, LLC
Project Owner: TxDOT
Engineer: Profile Consultants, Inc.
Precaster: Speed Fab-Crete
Completion: August, 2014
In June 2012, Profile Consultants, Inc. began designing integrated precast panels to serve as the sound barriers for approximately 7.8 miles of frontage road and highway areas on the east and west segments of the North Tarrant Expressway project. The project involved civil and structural engineering of 12 independent sound barrier wall packages using integrated precast panel configurations.
Highway sound wall systems have traditionally used a mix of precast or steel columns and individual precast panels at regular intervals on concrete drilled pier shafts as primary structural components. However, to reduce transportation costs, construction erection timelines and the number of components required, an integrated precast wall system was developed. This solution includes a precast concrete column in the design of the panel, resulting in a monolithic system. Thanks to the integrated design, several panels can be installed and transported quickly once foundation piers are in place.
The panels use a high-yield, 5,000 psi concrete mixture with welded wire reinforcing fabric. The integral columns are reinforced with grade 60 reinforcing bars and cast in conjunction with the panels. Each column is also cast with voids at the base, allowing connection to the concrete piers. The voids are then grouted when the panels are erected. During the grouting procedure, a low and a high weep hole is drilled near the top of the cavity to ensure grout has filled the void. Unlike traditional wall systems, the connection does not require any secondary steel plate or anchor bolts. Panels are lifted in place and managed by lifting inserts installed during casting.
Various form liners can be used on the panels to achieve specific aesthetic requirements generally mandated by local municipality zoning ordinances. The integral panel configuration’s standard widths are 12 ft and 18 ft. Special panels can be used at locations requiring a specific width. Panel heights can also vary from 8 to 19 ft.