Lone Star Constructors, NEX

The extensive documentation of every step in the creation of bridge support structures – from soil testing and drilling data to the concrete mix and the composition of reinforcing steel – would fill a website. Oh, wait. That’s exactly what we’re doing on the first phase of the I-35 NEX South project. For the first time in TxDOT history, every process, date, and data point from planning to completion is being collected on a site that can be accessed by scanning a QR code on a bridge column. Accessing the information requires special software. That’s useful today, but the real value could come years from now when a TxDOT crew who didn’t even work on this project can quickly access a complete record and know when the structure was last painted, if it’s ever been damaged and repaired, and what specifications it was built to. Fun Fact: While our QR code is a Quality Record, QR in the original two-dimensional barcode stands for Quick Response. It was invented in 1994 by Denso Wave of Japan to track vehicles and parts during manufacturing.

What could be more dangerous than maneuvering to avoid debris on the highway? Maneuvering to avoid a person cleaning debris off the highway. That’s where the “South Texas snowplow” comes in. It’s a blade mounted to the front of a truck that’s used to push debris off the roadway, where it can be safely cleaned up. It wouldn’t be very useful if we did get snow in South Texas, but it can push objects as large as stalled cars out of traffic lanes – keeping both motorists and road crews safe. #TxDOT #I35NEX #my35 #LSCNEX #highway

A talking Santa, a singing Grinch, and live music. Griswoldesque light shows and sweet treats. Down-home displays and full-on theme executions. Our first holiday office decorating contest had it all.

‘Tis the season for celebrations. Today we celebrated a safe year on the first phase of I-35 NEX South and doubled down for 2025 with a safety banquet for the team and a presentation on key safety takeaways from 2024.

The strip of concrete on either side of the wall dividing northbound and southbound traffic on I-35 looks fine. So, what’s up with the construction weekend after weekend? That eight-foot strip, called a median, is fine, for a median. But medians are built as safety zones, not to support traffic, and we have bigger plans for that strip as we progress with construction. We’re building an above-average median on I-35 between Walzem Road and Petroleum Drive – replacing the existing surface with 18 inches of asphalt. That will enable us to shift traffic onto that strip at times as needed during construction, providing more driving space for travelers.

At peak construction, the first phase of I-35 NEX South will pour 40 mixer trucks of concrete a day, each with a capacity of 10 cubic yards. And we’re just one of the five projects that make up the 20-mile I-35 NEX corridor. Volume alone would make having a dedicated concrete plant for the project useful. But it’s precision that makes the plant necessary. The concrete mixes for an apron and a bridge column are different. The plant produces 14 mix designs based on TxDOT specifications for different applications. A mix includes one or more of five different types of aggregate, from one-inch crushed rock to silica sand. The binder can be cement, fly ash, or slag. And there are seven chemicals that can be added to change the way a batch cures and its finished properties, like durability and load-bearing capacity. Those ingredients are mixed with water from an insulated tank with a 90-ton chiller that keeps it cooled to 35 degrees. Concrete Fun Fact: Concrete is the second-most-used substance in the world after water, and it is the most widely used building material. Ton for ton, concrete usage is twice that of steel, wood, plastics, and aluminum combined. 

Picture escaping southbound I-35 traffic coming into San Antonio by entering elevated lanes in Guadalupe County that zip you 60 feet above the I-35 mainlanes to beyond the I-35/I-410 south interchange, bypassing Loop 1604 and I-410 if you choose. The structures below will support the exit ramp where you’ll be touching down.

Your GPS telling you to exit in 100 feet is fine for driving directions. However, that level of accuracy is not very useful when you’re building an exit ramp. Still, did you know that GPS (Global Positioning System) is a critical highway construction tool? By combining GPS signals with the beacon from its base station, a drone can map points to centimeter-level precision. The drone takes thousands of pictures that are stitched together and overlaid on commercial satellite maps and engineering plans, providing a high-definition view of the state of construction at a moment in time, with context for the surrounding area provided by the commercial map. The red marks on the photo above show where elevated roadway will be built.   Survey crews on the ground verify the accuracy of the data and ensure that all measurements meet the required standards and specifications. That level of precision and accuracy are critical when the project involves building roadways 50 feet off the ground that connect in midair with spans built by another company, as we’re doing on I-35 NEX. Fun Fact: “precision” and “accuracy” are often used interchangeably, but they have distinct meanings. Precision refers to the consistency of a measurement. Accuracy refers to how close a measurement is to the true value. The survey crews verify that the very precise drone data is accurate.

24 years ago today was the last day in which there were no traffic deaths in Texas. Please help #EndTheStreak

At peak construction, the team on the first phase of I-35 NEX South Project (one of five projects that make up the 20-mile I-35 NEX corridor), will pour 40 mixer trucks of concrete a day, each with a capacity of 10 cubic yards. Volume alone would make having a dedicated concrete plant for the project useful. But it’s precision that makes the plant necessary. The plant produces 14 mixes based on TxDOT specifications for different applications. A mix includes one or more of five different types of aggregate, from one-inch crushed rock to silica sand. The binder can be cement, fly ash, or slag. And there are seven chemicals that can be added to change the way a batch cures and its finished properties, like durability and load-bearing capacity. Those ingredients are mixed with water from an insulated tank with a 90-ton chiller that keeps it cooled to 35 degrees. Concrete Fun Fact: Concrete is the second-most-used substance in the world after water, and it is the most widely used building material. Ton for ton, concrete usage is twice that of steel, wood, plastics, and aluminum combined.