Complex bridge construction over an active interstate requires contractors to coordinate structural work with worker access, emergency response and traffic conditions. Sundt is applying a detailed planning and mock-up process to construction of 104 bridge columns as part of the Texas Department of Transportation's SH 178 Artcraft Road Improvements project in El Paso.
The project includes four flyover roads connecting I-10 with Artcraft Road. The connections will cross six lanes of the interstate near the U.S.-Mexico border and are intended to improve movement through the area.
The four flyovers require 104 mast-placement columns, with some reaching 55 feet in height. The columns are being constructed using a bottom-up concrete placement process that requires workers inside the forms to consolidate the concrete as the structures are filled.
A four-person crew is used for each column, with two workers inside the form and two positioned at the top. The workers inside operate a metal vibrator to consolidate the concrete and eliminate voids that could affect structural integrity.
The construction team can place and consolidate approximately seven feet of column each hour. A 55-foot column requires roughly a full day of work.
Before beginning the column work, Sundt developed a full-scale layout of the column geometry on a warehouse floor using duct tape. The exercise allowed the project team to evaluate clearances, identify potential pinch points and review how workers would enter and exit the confined space.
The team also used the mock-up to walk through emergency and rescue procedures before workers entered the elevated forms.
Workers entering the columns use protective equipment, including harnesses connected to a winch system mounted at the top of the formwork. Blowers provide fresh air, while personal air monitors are used to identify potential fumes or low-oxygen conditions.
The retrieval system allows workers above the column to remove an incapacitated worker without requiring another employee to enter the space for a rescue.
Construction is advancing across the four bridge structures at different stages. The first phase of the main bridge has completed its caps and columns, while crews have moved into girder installation and deck placement.
As of the latest project update, 70 of the 104 mast-placement columns had been installed.
Core structural work is expected to be completed in summer 2027.
The project demonstrates the planning requirements associated with performing concrete work inside tall bridge columns over an active interstate. For contractors, full-scale preconstruction mock-ups can provide a way to evaluate worker access, equipment placement and emergency procedures before crews begin work in difficult field conditions.
For transportation owners, the approach also highlights the importance of coordinating structural construction with safety planning when major bridge connections are built over existing highway infrastructure.
Source: Sundt.
