C+S September 2021 Vol. 7 Issue 9 (web)

Established in the mid-1800s, the still-booming metropolis of Houston, Texas is now the fourth largest American city with a population of ap - proximately 7 million people. The region’s tremendous growth began to take a toll on its roadways, including the critical North-South State Highway 288 (SH 288) transportation corridor. SH 288 traverses Harris and Brazoria counties between Houston and Freeport and provides a vital hurricane evacuation route for the com - munity. It is also a freight and commercial trucking route and connects directly to the Texas Medical Center, which is the largest medical complex in the world. With worsening congestion resulting in safety issues, the community needed a solution. The SH 288 Toll Lanes project delivered, expand - ing roadway capacity with four toll lanes within the existing SH 288 median, and preparing the city for serious growth. Working with myriad partners on a $850 million mega project This $850 million Design-Build-Finance-Operate-Maintain (DBFOM) project encompassed a 10.3-mile segment of SH 288 from US 59 to the Harris County line. Stantec served as the engineer of record and led the design for the project, which was developed through a public- private partnership P3 between the Texas Department of Transporta - tion (TxDOT) and the Blueridge Transportation Group and built by Almeda-Genoa Constructors. The project was awarded to the team in February 2015 and design was substantially completed in June 2017. Careful coordination with the contractor, stakeholders, and adjacent projects is critical to the success of a large project. During the design phase, Stantec’s key team members co-located on site with the contrac - tor to ensure open and constant communication between all parties, which in-turn allowed the work to progress faster than a usual design- bid-build project. By maintaining an open dialogue, we could quickly address issues and changes to the design as needed. Once the design was complete, Stan - tec maintained an on-site construction support services (CSS) team with structures and roadway engineers to allow for seamless coordina - tion around construction obstacles. Deploying the design resources for an accelerated timeline The project was designed in just under 13 months, and construction began nine months after the Notice to Proceed for detailed design. To meet this challenging schedule, the design team completed preliminary Everything’s Bigger in Texas: A P3 Mega Roadway Project Comes to Life on an Accelerated Timeline By Youssaira Belmokadem and James Rashford

Aerial of SH 288 and IH-610 Interchange, February 2020. Photo:Almeda-Genoa Constructors and AeroPhoto

grading, drainage, and bridge substructure designs several months prior to the construction start. In fact, the design team completed a total of 8,354 design drawings, 380 submittals and nearly 120 design packages in 12 months leverag - ing more than 150 Stantec design professionals and support staff from 15 offices in the U.S. and Canada, along with 10 subconsultants. The aggressive schedule required constant collaboration between the multiple design teams to achieve conformity and standardized designs that met the contractor’s dual needs for economy and con - struction speed. The project included 40 new bridges with eight connector ramps to and from Beltway-8 and eight connector ramps to and from IH-610. The new infrastructure also features two direct connectors to Holcombe Boulevard near the Texas Medical Center, improving commute times for healthcare workers and supporting emergency medical response. The project also included the modification of 13 bridges for a total of 1.8 million square feet of bridge deck along the corridor. Bridge construction was accelerated by using as many precast elements as possible, and because elements could be mass-produced off-site, schedules became more flexible. One innovative component of Ac - celerated Bridge Construction used on the project is precast caps with voids. The voids were used to reduce dead load for lifting operations to accommodate the contractor’s request for a 200-ton weight limit to ease installation and make use of available equipment. Designers were challenged to come up with a precast cap to single- column connection in order to preserve the bent configuration required by aesthetics. TxDOT already has standards for multicolumn bents with precast caps, but this project required the use of a single column bent type. The precast details for the bent caps (i.e., connections, grout pockets, lifting weight, etc.) had to be carefully considered to be both durable and constructible. Once the column was ready for the precast cap, installation could be completed in a matter of hours.


september 2021


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