Since its first introduction to the construction industry in the late 1800s, the composition, patterns, applications and state of performance of corrugated steel pipe (CSP) and structural steel plate systems have been assessed to provide insights into overall performance and effectiveness. Because of its potential hundred-year lifecycle, CSP is proving to be a real winner for owners, contractors, engineers and specifiers in private and public civil construction projects throughout the United States.
The National Corrugated Steel Pipe Association (NCSPA), formerly known as National Corrugated Metal Pipe, was established in 1956 and is headquartered in Dallas, Texas. The association functions as both advocate for and educator about CSP systems. The NCSPA promotes the many benefits of these systems for those specifically engaged in the civil construction sector.
Mike McGough, the association’s Director of Technical Services, states that the mid-1950s, “was when the highway industry was really beginning to explode. That’s when the Interstate was founded and when Eisenhower began to build across the country. The industry began to grow really fast.” Corrugated steel pipe (CSP) and structural steel plate systems are used extensively for drainage systems such as sewers, culverts, bridges, storm water management, and fish passage projects.
The NCSPA currently has twenty-five member companies comprised of pipe and plate fabricators, mill suppliers, dealers, distributors, and product coaters. There are also affiliate members from the international community. The association estimates that its fabricating company members are the producers of nearly ninety percent of the nation’s pipe production. NCSPA has member companies located throughout the country which allows them to better serve our nation’s owners.
Other sectors represented by NCSPA’s members include forestry, highway construction, mining, railroad, and utility construction. “There are a number of specialized markets,” says Mike. “These are all companies that are involved in the production process. They have to go through approval processes with the various specifiers. The states and the purchasers work together to set up the quality assurance programs.”
The NCSPA is comprised of six corrugated steel pipe associations representing the Great Lakes, Southeast, Northeast, South Central, North Central, and Western regions. Each of these regions has a technical and promotional committee and a board with elected presidents.
The Board of Directors oversee the NCSPA’s Technical Advisory Committee (TAC) which is responsible for developing all technical specifications and standards of CSP and has a close affiliation with other organizations such as the American Association of State Highway and Transportation Officials (AASHTO), American Society for Testing and Materials (ASTM), the National Association of County Engineers (NACE) and the Association of General Contractors (AGC).
The TAC is composed of, “a group of engineers from the various member companies,” explains Mike. “We conduct research and drive changes to specifications [and] improvements for the end user.” This committee looks at design and installation criteria, hydraulics, durability, and life cycle cost analysis. “That’s their primary role.” The Product Promotion Committee is responsible for all aspects related to education and publicity resources including webinars, social media, advertising, marketing, and website content.
Within the coating process, there are various protections for corrugated steel pipe which include galvanized steel (the most employed) and Aluminized Type 2. “Polymer coated pipe is another option,” says Mike.
The recommended coating option will depend on environmental and site conditions, including abrasion levels and the pH and resistivity of the water and soil. The proper coating selection enables a service life of up to one hundred years. Studies have suggested that without the appropriate coating, the life expectancy of CSP declines to about ten to thirty-five years, after which metal perforation occurs.
Corrugated Steel Pipe has garnered much interest because of its many benefits. It is manufactured to exacting specifications. The resulting high quality product can be aesthetically pleasing and is also easily installed, durable, economical, and sustainable.
Mike says that another merit of CSP is, “in the design flexibility of the product.” Its design flexibility enables for the fabrication of various angles, geometries, and long lengths that are essential for projects involving culverts, storm sewers, underpasses, and bridges.
Steel is sustainable. “Steel is the most recycled product in the world,” Mike adds.
The NCSPA offers a number of resources to its members including technical information. On its website are studies, guides, reports, and various calculators for determining pipe and plate service life and water quality systems. Also included is its load and resistance factor design (LRFD) calculator to calculate fill heights and the gauges required to design a culvert or storm drain pipe. All of these calculators, “make some of the design aspects a little bit easier,” says Mike. Seminars, college presentations and The Real Deal on Steel E-News publication are also part of its educational outreach.
“Our primary resource is the Corrugated Steel Pipe Design Manual,” says Mike. “For someone who really interested in using the product, it’s extremely comprehensive. It’s easy to navigate through and a great resource.” This manual assists engineers with various specifications such as those related to ASTM and AASHTO.
The NCSPA is closely affiliated with a number of other agencies and organizations, each of which supports a stronger voice and the sharing of information to all NCSPA’s members. “These are our customers, in most cases. You want to make sure that your customers are being kept happy,” Mike says. “Our members have a level of relationship with the states they serve. We find it beneficial to have the association serve as the liaison to these communities. It’s a way for everyone to have a voice.” Perhaps more importantly, “we want everyone to know that we’re here to serve as a resource and provide them with information, data and research on our products.”
President Trump has pledged to launch an infrastructure stimulus package of one trillion dollars in an attempt to modernize infrastructure and create jobs. The capital for this investment is expected to be financed through public and private partnerships.
“We are definitely advocates of the administration’s agenda to push for additional infrastructure spending,” says Mike. He notes that the FAST (Fixing America’s Surface Transportation) Act passed a couple years ago was, “a much needed reauthorization package… You see construction moving in a positive direction.”
Buying American products and using U.S. steel have also been touted by the current administration. “So those are positive signs for our members. The mills are a large part of what we do,” continues Mike. “Mills are idle in capacity right now, so they certainly have reserved capacity to ramp up should an infrastructure package come through. There’s certainly room there to grow.”
He adds that, “Anytime you have competition, it creates a win-win situation for taxpayers. You have competing products putting their best foot forward in that type of atmosphere.”
“I think the challenges today are probably no different than they have been for the last couple of decades. It’s a tough business competition wise,” affirms Mike. “Plastic pipe, concrete pipe, and steel pipe are all fighting for market share.”
Looking to the future, the NCSPA hopes to develop additional resources to aid owners, engineers, contractors, and designers. Mike would like to see more research and product development such as, “different coatings or higher strength steels. I think those are all potentials over the course of the next ten years. Technology is moving fast. I think companies are always trying to innovate. When you have that, it benefits everybody.”