Post-World War II Bridges: Innovations and Leadership
The Texas Historical Commission (THC) is working with the Texas Department of Transportation (TxDOT) and the Historic Bridge Foundation (HBF) to share the stories of the evolving bridge technology from the decades following World War II. From 1945 to 1965, engineers in Texas worked with new materials and construction methods to develop innovative approaches to bridge design. Some bridges from this time period are the earliest examples of technology eventually adopted as national standards or that served as important steps toward a better understanding of steel and concrete. Learn more about this period in bridge building here.
More than 100 of these bridges have been determined eligible for listing in the National Register of Historic Places, but many of them are not good candidates for long-term preservation. In an effort to streamline federal and state regulatory review, THC, TxDOT, and HBF sought public input about which are the most significant of the bridges and hosted open houses in July and August 2014.
Here are tables of bridges determined eligible for listing in the National Register. A preliminary map lets you explore them by location. They are broken into three groups in tiered levels of significance based on conversations between the THC, TxDOT, and HBF. To find out more about what gives a bridge significance, the photo gallery below features good examples of the various technologies and construction methods introduced and explored during the Post-World War II era.
The feedback we received over the summer 2015 was in support of the tiered, grouping approach, which will inform TxDOT about preservation priorities for these bridges. Please let us know what you think.
Bridges Built Between 1941–1965
When the United States entered the Second World War in 1941, the country focused on the war effort in the attempts to ensure proper defense. The railroad gradually lost fashion, with increased attention towards highway construction, enabling easy troop and tank transport. Finished in 1942, the Lamar Boulevard Bridge transported military trucks and tanks across the Colorado River. It remains one of the last Art Deco style, open spandrel concrete arches built in Texas. Starting in 1941, the United States focused most of their energies on the war effort, with new technology and research for better defense. Since steel grew to be so high in demand, bridge engineers looked towards alternative materials, primarily concrete.
Once WWII ended, various cultural changes arose that directly influenced bridge building. Middle-class families moved out of central cities and into the suburbs, the automobile grew to immense popularity, and a new minimal movement replaced the Revival focus in architecture.
With the triumph of democracy over fascism, a spirit of optimism spread throughout the nation. With this, engineers and architects applied simple designs onto buildings, houses, and bridges. In Texas, the Texas Highway Department standardized bridge design to improve efficiency and speed, which resulted in less ornate constructions than previous infrastructural projects.
In this era, form followed function, and bridge design rejected decorative detail and embraced clean lines. Engineers experimented with different types of concrete and invented reinforced and pre-stressed concrete, which allowed concrete bridges to span greater distances and carry greater loads.
The bridges most familiar to us today, the ones we drive on and pass every day, can all be traced back to this post-war period, which saw the formation of a new, minimal, concrete world.
Sources for information and images can be downloaded here.
A Fresh Start at the End of World War II
Texas and the rest of the nation rejoiced when World War II ended in 1945. Victory energized the population as the war improved the economy. Life suddenly felt very different from the Great Depression in the 1930s. The road ahead was ripe with opportunity. The Texas Highway Department (THD) changed the state’s highway system in this post-war era more than any other time in its history.
A Real Roadblock
Construction stalled during the war due to serious shortages of concrete, steel, and manpower. As soldiers returned and the population of drivers increased, people were on the move. The Texas transportation system was a real roadblock. In 1945 Texas had more dirt roads than paved. These outdated roads meant that drivers risked unsafe bridge crossings or getting stuck in deep mud during the rainy season. Texas growth created a critical need for a new network of roads and bridges. It was a challenge as big as Texas.
THD Ensures Safe Crossing into a New Era
THD anticipated this transportation problem and planned for it during the War. Gone were the days of wartime shortages. With new funding from the federal government, plans for roads and bridges were put into motion.
In order to connect Texas’ many rural communities, the farm to market road (FM road) system became a THD priority. THD began building 36,000 miles of roads that connected farmers and ranchers with growing cities. The project helped rural communities become less isolated and bring their products to market.
With that many new roads THD had another challenge – building all of the river and stream crossings for the new or upgraded routes! Bridges that were safe and quick to build were badly needed, not just on FM roads but on new freeways and improved city streets as well.
From Postwar into the Future
Between 1945 and 1965 cooperative research teams at THD, the University of Texas at Austin, and Texas A&M University rose to the challenge. These collaborations produced many innovative ideas. Some were completely new, while some were based on work done elsewhere in the country and adapted to the needs of Texas. The teams also took advantage of technological advances like pre-stressed concrete, neoprene pads and high tensile bolts.
Combined with the know-how of the engineers, new technology allowed for the creation of brand new bridge designs. The bridges could be built inexpensively, safely, and quickly. In fact, two new types of bridges were invented right here in Texas: the pan-formed girder bridge and the FS slab bridge. Thousands of these types of bridges were built all over Texas.
THD engineering even allowed for clever adjustments to market pressures. For example, when the Korean War created another steel shortage, engineers focused on building prestressed concrete bridges. When steel was available again, engineers designed lighter and stronger steel bridges that used less steel and were cheaper.
TxDOT Continues THD’s Legacy
THD’s hard work paid off. By September 1965 Texas had over 15,000 new bridges – that’s a rate of 2 bridges a day for two decades! The pre-war sparse network of muddy roads that took years to upgrade were a thing of the past. THD’s bridge program supported growing communities, made valuable connections between rural and urban areas, and helped Texas become an economic powerhouse. Today, the Texas Department of Transportation (TxDOT) keeps going Beyond the Road as it continues to support connections that matter to Texans.
Between 1945 and 1965, the Texas Highway Department constructed more than 15,000 new bridges and thousands of miles of roads to upgrade infrastructure and serve an expanding population. To learn more about some of the most unique of these historic bridges from 1945–1965, see the Post-World War II Bridge Highlights.
