Longview Bridge & Road Crews Overcome Floodplain on U.S. 69

Tue December 01, 2020 - West Edition #25
Irwin Rapoport – CEG Correspondent

LBR Project Manager Alvaro Lopez Jr. (L) poses with a little helper, Julian.
LBR Project Manager Alvaro Lopez Jr. (L) poses with a little helper, Julian.
LBR Project Manager Alvaro Lopez Jr. (L) poses with a little helper, Julian. The remainder of the work consists of installing barrier rail, adjacent roadway and ramp tie-ins and FM 346 roadway tie-ins under the bridge. 
Flooding issues have plagued U.S. 69 for years. Crews from Longview Bridge and Road helped alleviate those problems by building a new overpass. The prestressed girders were selected to optimize span length, structure depth and foundation elements. The hydraulics and the drainage impacted the project when heavy rains were experienced at the initial phases of construction. New materials should include: more than 4,400 cu. yds. of structural concrete, 44,400 tons of asphalt and 515,842 lbs. of steel.

Longview Bridge & Road Ltd. (LBR) is building a new 690-ft.-long overpass bridge (two lanes in each direction) on U.S. 69 spanning FM 346 in the city of Tyler to improve traffic flow in the largest municipality in northeast Texas.

LBR crews have been on-site since October 2018 and are expected to complete their work next spring. The other elements include paving adjacent sections of U.S. 69, culvert work, retaining walls and roadway tie-ins on FM 346.

The Texas Department of Transportation (TxDOT) project comes at a cost of $16.7 million. CP&Y Inc. designed the new prestressed concrete Tx46 girder-type bridge and associated infrastructure. The six-span bridge is 80-ft. wide with a 20-degree skew structure.

"The spans utilize prestressed concrete Tx46-girders ranging from 105-foot to 120-foot in length," said Paul Schneider, area engineer of TxDOT's Tyler district. "The skew of the overpass is set to match the underlaying FM 346 roadway and is constant throughout the structure. Given the width of the bridge, not varying the skew eliminates a significant variance in length between exterior girders and instead allows for the same length girder to be fabricated for a given span.

"Slab and girder deflections also remain relatively similar within a span," he added. "The prestressed girders were selected to optimize span length, structure depth and foundation elements. Additional benefits include their cost effectiveness and familiarity amongst local contractors. The railing and aesthetics of the bridge and retaining walls were designed to match the interchange of U.S. 69 69 at FM 344, 5 miles to the south."

Construction Progress

LBR has completed the main bridge structure and major culvert work. The remainder of the work consists of installing barrier rail, adjacent roadway and ramp tie-ins and FM 346 roadway tie-ins under the bridge.

"The floodplain and creek also affected construction," said Alvaro Lopez, Longview's project manager. "The hydraulics and the drainage impacted the project when heavy rains were experienced at the initial phases of construction, which caused delays. These issues were addressed with appropriate drainage and underdrain installation. Additionally, careful planning and resource loading to expedite subgrade and structure work when weather allowed. After the award of the project, only a couple weeks are allotted before the notice to proceed, but our management team and field staff spent the essential time to plan and review how the bid was composed in order to deduce the proper execution plan. However, the team constantly readjusted the plan to match the changing conditions.

"We mainly conduct work during the day, but due to the restricted lane closure times – 9 a.m. to 4 p.m. — we change shifts to accommodate the nature of work that requires closures, which includes traffic switches, pavement operations, beam sets and critical structure work," he added. "This is a tight work zone due to the traffic configuration, but with help of lane closures and TCP plans, we are able to work through these circumstances. TxDOT is our main client and we always strive to continue the great relationship we have with them. Construction issues are inevitable in our industry, but with partnering we always find the most optimal, safest and cost-effective resolution in a timely manner."

The construction sequence and plan of attack proceeded with shifting traffic on the insides of the pavement using temporary pavement to reconstruct NB and SB of U.S. 69, along with the necessary storm sewer and culvert adjustments.

"This was followed by continuing, traffic shifts on outside NB and SB U.S. 69 and culvert work on inside and middle portions," said Alvaro. "We then proceeded to construct the bridge structure along with MSE retaining walls in this second phase, as well as completing the U.S. 69 transitions and main lanes. Traffic was then shifted to its final configuration, and we completed the remaining storm sewer work and constructed the inner portion of U.S. 69 ramps and FM 346 U-turn."

The last aspect had traffic shifted onto FM 346 to complete remaining work — leveling up the U.S. 69 main lanes, finishing the final driveways and access to the cross streets, and placing final pavement markings along with landscape work.

Elements of the bridge were prefabricated, including 36,718 sq. ft. of prefabricated concrete deck panels from Austin Prestressed Company, 8,096 linear ft. of TX 46 concrete girders from Texas Concrete Partners, 30,000 sq. ft. of MSE wall panels from The Reinforce Earth Company, and precast drainage items from Forterra.

"Our deck pours consisted of two separate pours, which were conducted at night for temperature control and traffic closures," said Alvaro. "Our Bidwell bridge screed paver played an essential role on this scope of work. Additionally, East Texas Concrete Pumping provided great assistance to the pour of this deck."

Safety was a constant for the bridge work.

"We have safety cable systems that are installed for our bridge work and we also use an engineered safety overhang rail system," said Alvaro. "Our safety record has been good, and we plan to close out the job with the same record."

The management team also includes Superintendent George Davidson; General Superintendents David Talancon and John Clemens; Longview Vice Presidents Robert Adamson and Reece Sterling, President Casey Johnson and CEO Larry Johnson.

"The team dynamic plays an important role in our success," Alvaro said. "We are fortunate to have crew leaders with many years of experience that constantly push our employees to provide quality work. Our field crews sacrifice countless hours from night and day to build and improve our infrastructure."

Peak days had 75 workers on site. The main subcontractors are: Striping Technology L.P. for electrical, striping and large signs; Issacs Construction Services for small signs and erosion control; M&D Foundation Drilling Industries for drilled shafts; Morris County Contractors for MBGF, CCA and object markers; and Wolfe Construction for seeding.

Earth work and excavation accounted for 60,983 cu. yds. of embankment and topsoil, 20,121 cu. yds. of excavation, and 45,508 sq. yds. of cement treated subgrade.

"Longview Bridge and Road has a sister company, Wood County Asphalt, that produces multiple asphalt products which allows us to recycle RAP [reclaimed asphalt pavement] for our projects," said Alvaro. "Additionally, we have a concrete crusher which we use to recycle concrete paving and base removal. LBR has a commitment to recycle materials to make improvements for the community by avoiding waste and keeping material as well as the work in east Texas."

New materials should include: more than 4,400 cu. yds. of structural concrete, 44,400 tons of asphalt, 515,842 lbs. of steel, more than 8,000 linear ft. of concrete girders and 30,000 sq. ft. of MSE retaining wall.

"Hydraulic leaks, hoses, radiator and routine mechanical maintenance is where we find our on-site mechanic very beneficial," said Alvaro. "Keys to successful maintenance are performing required daily inspections and properly reporting any issues/malfunction to our mechanical department."

Longview purchases and rents equipment from Holt CAT, Howard-McAnear Equipment, Louisiana Machinery and Bane Machinery, as well as United Rentals and Sunbelt for small equipment needs.

Bridge Information

The new bridge, financed by state and federal funding, is expected to carry 16,600 vehicles daily when open to traffic and 21,800 vehicles by 2036. The structure is being built in the southern part of the city, in an area consisting mainly of commercial properties with adjacent FM (farm to market) roads feeding residential areas. It serves as the main corridor for those that commute from the south to and from Tyler.

"The new bridge will decrease the commute time and increases safety by eliminating a signalized intersection and allowing a continuous traffic flow over the current at-grade intersection," said Schneider.

"Henshaw Creek crosses the U.S. 69 corridor immediately south of FM 346, and it and the associated floodplain influenced the design in several ways," said Schneider. "The hydraulic analysis of the creek indicated that roadway embankment approaching the bridge could not be present within 500 feet of the south side of FM 346. To accommodate the hydraulic needs, the bridge includes additional spans on the southern approach of the bridge, as well as the installation of a new box culvert structure under the frontage roads.

"In addition, water-bearing sandy soils were discovered in the geotechnical investigation," he added. "The use of casing or slurry displacement was noted in the plans to address any potential hole integrity issues during drilled shaft construction. Underdrains were also used under the southern spans of the bridge to convey groundwater from the site."

The construction phasing design allows the bridge to be constructed in a single phase, reducing overall construction duration and eliminating multiple mobilizations of construction crews.

The traffic management is based on occasional lane closures of U.S. 69, mainly along U.S. 69 near the intersection of FM 346, with the speed limit reduced to 60 mph in the work zone. CEG

Equipment Used

Cranes:

Link-Belt 218HSL

Link-Belt 118

Grove RT 750

Excavators:

Cat 325E

Cat 329E

Komatsu PC210

Dozers:

Cat D5

Cat D6

John Deere 750

Motor graders:

Cat 140M

Cat 140H

Loaders:

Cat 950G

Cat 924G

Komatsu WA380-8

Rollers:

Ingersoll Rand 125R

Cat C5S

Volvo SD100

Pavers:

Roadtec 4223

Cat AP 100E