Pent-up demand charges prestressed-pole producers Deregulation of electric power supply, the growth of the cellular phone industry, and local governments flush with cash as the result of the booming economy, are driving sales of a variety of sizes of concrete utility and lighting poles. Improvements in our nation's electricity transmission and distribution (T&D) grid as it is upgraded in the face of utility deregulation has the potential to move a lot of these speciality concrete products, and already is resulting in some increased sales. But the big boom has yet to materialize.

"A tremendous amount of lines are going to go up, and they will be bigger and taller," reports Dr. Fouad H. Fouad, P.E., who chairs ASTM C27 Precast Concrete Products and PCI Precast Concrete Poles committees, as well as the University of Alabama-Birmingham's Civil and Environmental Engineering Department, where he is likewise professor.

How tall? "In the 1960s or 1970s they would be in the 70-foot range," Fouad tells Concrete Products. "In the 1980s and 1990s, they were in the 80 to high-90-foot range. Now, they're getting in the 100s."

But this trend won't necessarily favor steel over concrete, he adds. "If you use new, improved splicing technologies and higher-strength concretes, concrete can compete against steel." he says. Now, Fouad is researching use of bottom and fly ash, bonded with cement, to replace conventional aggregate to create super high-strength concrete utility poles.

In the meantime, the explosion of cell phones and the wireless communications poles needed to support their use has created a new market for concrete poles. At the high end of the market, in the high-voltage transmission sector, steel appears unassailable in terms of cost, but new research in the engineering of higher, hybrid concrete poles may change that. At mid-market, distribution lines are being served by concrete, wood, steel and even fiberglass composite poles. At the lowest product level, municipalities are choosing decorative concrete light posts over fiberglass composite posts, depending on market location and proclivities.

But concrete light standards also find growing sales in recreational applications such as amateur sports field illumination, flagpoles and even posts to support netting around landlocked golf driving ranges. And Fouad is investigating use of concrete poles for power-generating windmills, as is done in Germany. One thing is common: They're all important fields of growth in concrete utility poles and lighting standards.

Need for T&D lines not met The U.S. national power grid was never designed for the large scale power "wheeling" that is commencing under utility deregulation. Instead, over the decades of regulated electric supply, adjoining power networks were connected so suppliers could share power in the event of a temporary shortfall or generating outage.

But now this system is being called on to distribute electricity from coast to coast. "Historically, the transmission system was designed to move power from a utility's generators to its own load centers," said David Nevius, vice president, North American Electric Reliability Council (NERC) at a Senate hearing in July 1999. "Interconnections between utilities were established for emergency situations, to share installed generation reserves, and to take advantage, from time to time, of their neighbors' lower cost generation. Now, the interstate transmission grids are being called on to move vast amounts of electricity from one region of the country to another.

Lines, demand out of balance Wholesale power sales by nonutilities to utilities, and wheeling (the transmission of power from one point to another) by utilities, have grown at 21 percent and 6.9 percent average annual growth rates, respectively, between 1986 and 1995, NERC reports. But few new T&D lines have been placed. Nowhere is this more clear than in a recent document issued by NERC, which demonstrates there is a pent-up need for new T&D lines.

"Customer demand is continuing to grow," NERC noted in Reliability Assessment 1999-2008, issued May 2000. Actual growth is higher than projections and a strong economy is driving this growth faster than projected.

But new transmission lines are not keeping pace. "Very few bulk transmission line additions [are] planned," NERC officials find. "Only 6,978 miles of new transmission (230 kV and above) are planned throughout North America over the next 10 years. This represents only a 3.5 percent increase in circuit miles, but an increase of about 400 circuit miles over last year's projection. As the demand on the transmission system continues to rise, the ability to deliver energy from remote resources to demand centers is deteriorating."

But this pent-up demand will not be unleashed unless order comes to state and national utility deregulation, securities analysts contend. "Unless regulators see the light, reliability could decline and congestion increase in the electricity grid, because transmission owners seem reluctant to invest under the current regulatory regime," notes Saloman Smith Barney's Leonard Hyman, senior industry advisor, in the March 2000 Cogeneration and Competitive Power Journal.

Deregulate T&D, like generation Grid expansion is strangled in part because electric deregulation has been confined to power generation, but not transmission and distribution. With no direction in this sector construction of lines has languished.

"The deregulation of transmission and distribution - the network of towers and wires and poles that make up what amounts to an interstate electric highway system - has not been brought into play," noted Competitive Enterprise Institute's Wayne Crews in testimony last year before the House Subcommittee on Water and Power Resources.

"About 600,000 miles of high-voltage transmission lines and about 2.5 million miles of distribution wires crisscross America," Crews said in his plea for complete deregulation of electrical supply. "Whether that is or is not enough is a question that only the marketplace can answer."

One important step to unfettered transmission and distribution will be the ability for the industry to self-police the renewal and operation of the transmission system. And here there is recent progress. If passed, current federal legislation initiatives will pave the way for NERC to establish self-regulatory oversight of the transmission system, encouraging needed T&D investment.

The Senate passed NERC-endorsed stand-alone reliability legislation, The Electric Reliability 2000 Act, at the end of June. The House Commerce Committee did not take up comparable legislation before it recessed for the Republican and Democrat conventions, but in late July, Rep. Albert Wynn (D-Md.) introduced a stand-alone reliability bill, HR-4941, based largely on what NERC and its partners say they need to support a reliable electricity grid.

Concrete stands ready Specialty-prestressed producers are ready to capture sales as the T&D market catches up with needs - and concrete stands tall against steel, wood and fiberglass composite alternatives.

"There's not a good, feasible way to get electricity from one side of the country to the other," notes Doug Sherman, P.E., vice president of Newmark International, Inc., a Pfleiderer Company. "There is no national system that's strong and stable enough to carry that kind of demand. We need an interstate highway system for electricity. We need long, powerful lines that can move a lot of electricity very quickly." Newmark is a major supplier of concrete utility poles and has the largest share of the T&D market, he adds.

And concrete is ideal for that infrastructure. "Precast utility and lighting poles endure long past their wood counterparts," according to the the Prestressed/Precast Concrete Institute (PCI). "The fact that they are cost competitive and virtually maintenance free is an added benefit derived of quality engineered concrete."

Concrete poles are nonreactive with the soils, water and air of the biosphere, PCI notes. "Protective coatings or chemical injections are not required to insure a useful service life."

The U.S. Air Force architectural guide lists concrete poles as the first choice for base lighting use. The USAF Landscape Design Guide puts concrete poles first, stating that for base use concrete poles are available "in a variety of finishes and are compatible in character with most settings, from roadways to pedestrian areas. Concrete poles are moderately expensive but require little long-term maintenance."

The USAF guide states that concrete poles are appropriate for most applications but cannot exceed 50 feet in height, adding that "as they approach this height, increased diameter may, depending on the setting, appear visually out of scale."

What about Brand X and Y? "Aluminum poles are also available in a variety of finishes and are appropriate," the USAF Landscape Design Guide states, but adds that "They are relatively expensive." Other choices are much less appropriate, the agency contends. "Decorative wood poles should be avoided because of high initial costs and high long-term maintenance requirements. Lights mounted on wooden utility poles should also be avoided because of aesthetic concerns. Painted steel poles, while relatively inexpensive, have high long-term maintenance requirements, and their use should generally be limited. Baked-on coatings help reduce this maintenance requirement but add considerably to costs.

New municipal products While Newmark focuses on T&D, another heavyweight, Ameron Inc. of Los Angeles, concentrates on lighting poles. "Our focus is on street lighting, although we do make distribution poles," notes Steven Bull, P.E., Ventura, Calif.-based field services manager.

Ameron works hard to create new, decorative designs that will play well with well-heeled municipalities undertaking civic improvement projects. "There is a lot of interest across the country in replicating the old cast iron poles from the turn of the century, and we've developed methods of manufacturing those," Bull says.

His company has also found success with a method of internally bolting prestressed poles so they mount exactly the same as the old cast iron poles. "We use the anchor bolts of the existing foundation, setting the pole on top and using the void inside the pole to bolt from the inside. This eliminates the flange and allows municipalities to change the look of their downtown streetscapes without having to put in new foundations. It greatly lowers overall project cost," Bull adds.

Ameron fights fiberglass light poles in some parts of the U.S., but not much in southern California where, the company finds, precast light standards have 90 percent market share.

A long history of development Ameron reports that in the U.S., the first concrete poles were marketed in Los Angeles by the American Cement Products Company in 1912. It says the first U.S. patents for concrete poles were issued in 1913 and dealt with simply reinforced concrete members. (By contrast, the first composite fiberglass light pole from Shakespeare was installed in 1967.)

In 1922, the first evidence of centrifugal spinning of poles was noted, Ameron says. Development of concrete poles for street lighting progressed from the 1920s through the early 1940s. In 1957, Florida prestressed pioneer Robert Finfrock patented his concrete H-framed pole and portal structure for overhead transmission line applications."These were used for structures such as those supporting 230kV lines in Florida, which are still in use," Ameron notes.

While prestressed concrete poles were seen in Europe and Japan in the 1950s, low-cost steel and energy discouraged domestic applications. But during the 1960s, prestressing was applied to concrete poles in the U.S., permitting the poles to increase in length while reducing their mass. "When the concept of prestressing caught on, so did the use of centrifugal casting," Ameron notes. "This gave rise to the round shape prevalent today."

Punching holes in wood While wood is cheap, it carries maintenance and environmental baggage. "The reliability of utilities' service depends first on the pole, which is the rationale behind the large investments operators make in poles," according to a 1994 report in Electrical World/Transmission & Distribution Magazine, a sister publication of Concrete Products now known as Transmission & Distribution World.

"Wood poles in service are subject to bio-deterioration from decay, fungi, and insects, which can result in loss of structural integrity and eventual failure," the magazine notes. "Structural evaluation of wood poles is most often performed for utilities by inspection and/or treating contractors, who use rather crude hammer sounding and boring techniques ... Reliable evaluation is complicated by the fact that wood is a natural material which varies greatly in strength."

Even the animal kingdom poses problems for wooden poles: Virginia Power has experimented with many products and methods to protect poles from woodpeckers, said the utility's Michael Brucato, senior coordinator of timber products, in that same magazine. "The utility spends over $10,000/year (in 1995) on epoxy fillers and splints to repair bird-damaged poles and expects to replace close to 200 woodpecker-damaged transmission poles a year."

To this, Newmark can counter: "Centrifugal casting creates the highest density and lowest permeability concrete available ... just ask the woodpeckers."

And the potential toxicity of wood preservatives has achieved attention. "Most in-service utility wood poles in the U.S. have been treated with either pentachlorophenol ("penta" or PCP) or creosote, amounting to approximately 36 million PCP-treated poles and 18 million creosote-treated utility-owned poles," reported the Electric Power Research Institute in its December 1997 report, "Pole Preservatives in Soils Adjacent to In-Service Utility Poles in the United States."

"Concerns have been raised regarding the possible levels of wood preservatives in soils and groundwater adjacent to treated in-service wood poles," EPRI noted, adding its report is intended to develop information about the concentrations of PCP and total petroleum hydrocarbons (TPH) in soils adjacent treated poles, and discuss release and migration of these preservatives in advance of potential Environmental Protection Agency (EPA) promulgations.

Composite fiberglass poles, while costly, are being marketed against wood for distribution lines. "A fiberglass pole costs about $900, compared with the $400 cost of a wood pole," reports manufacturer Shakespeare. The company notes that Pacific Gas & Electric Co. recently installed as many as 110 fiberglass poles near Yosemite National Park as a test. If the company is satisfied with their performance versus wooden poles, fiberglass poles may be incorporated in the utility's standards for use wherever serious woodpecker problems are encountered.

Jamming more into existing ROWs The expansion of existing utility rights-of-way or adding of new ones has become problematic, due to sheer economics and public opposition ("NIMBY"). And this could mean good news for high-profile concrete poles, versus H-profile wood and steel structures.Problems with getting new ROWs may mean reconfiguration from horizontal to vertical construction to make room for another line, wrote Bill Koch, P.E., in the December 1997 issue of Electrical World/Transmission & Distribution. "In others, replacement of existing wide-stance wood H-frame construction with narrower footprint designs using nonwood materials is being considered."

Koch said that in the late 1990s wood poles appeared to be the most widely used, with steel growing in popularity in the North and West, and concrete widely used in the Southeast and Southwest. Long poles from 35 to 125 feet in length were easily obtainable from second-growth plantation forests, he said, but their fiber strength was not as strong as the harder-to-obtain old growth poles.Lattice steel towers were losing ground to vertical, self-supporting steel poles, Koch wrote. Either steel configuration, though, was subject to corrosion, while wood poles were threatened by rot or migration of preservatives into the surrounding soil. These attributes of steel and wood enhance concrete's marketability. Little wonder that precasters see the transmission market - with its pent-up demand - as fertile ground.

Poles for other needs Sport and flagpole applications also are being served by concrete. In addition to its municipal lighting products, light standards for the burgeoning recreational market have been developed by Ameron. "From ballfields to tennis courts, Ameron can provide the pole you desire," the firm says. "These poles can be either steel or concrete, and can be provided in many colors, finishes and textures. These poles can have cages or bull horn mounts, and can be direct burial or anchor base mounted." And Ameron suggests an owner use concrete flag poles to match concrete used in a structure's parking lot, bollards, curbs and sidewalks, and building facade. "How many times have you visited a completed project and noticed someone had overlooked the flagpole matching the parking lot poles?" the firm asks. "How many times have you wanted the flagpole to match the surroundings? Ameron has your answer."

Hybrid structures on market There is a variety of hybrid structures which incorporate steel and concrete. One manufacturer that embraces steel is Newmark, which also says it's the No. 1 manufacturer of concrete poles in the U.S. The firm manufactures a wide variety of prestressed concrete and steel poles for specialty and custom projects. Although it sells steel poles for specific applications, Ameron has concrete poles available in a larger selection of designs and finishes than steel, aluminum or fiberglass poles.

"Ameron offers over 40 standard colors, aggregates and textures to make the largest selection of finishes in the industry," the firm says. Its poles come with a 10-year warranty, the longest in the industry, the firm says.The firm also supplies multi-piece structures made up to 180 ft. in height. Its NewPole product uses a patented tubular steel splice to provide a more functional connection between pole sections than traditional flange splices, the firm says, adding it will supply flange-spliced structures for those applications with special requirements."The 180-foot pole is basically made from two 90-foot poles slipped together in the field," Newmark's Sherman says. "Yet your crane only has to lift 90 feet of it at a time, so the maximum you are lifting is just half the weight at a time, and you can get by with a smaller crane, at considerable savings."

When a tree is not a tree Going full circle in the battle between wood and concrete for utility poles is Newmark's NewTree Disguised Wireless Communications Poles. NewTree poles are disguised to blend with their background and to enhance the woodsy layout of an area, calming neighborhood objections to ugly cellular antennae."It's a concrete pole disguised like a tree, with painted brown bark, and fiberglass branches that make it look like a tree," Sherman notes. "Some can look like pine trees, others like palm trees. They are textured on the outside of the concrete, with attachment points cast into the pole to which branches are attached at the site."

New ASTM method for testing concrete poles near balloting A new method for testing prestressed, precast concrete poles is near completion by a committee of the American Society for Testing and Materials (ASTM), according to Precast Concrete Products Committee Chairman Dr. Fouad H. Fouad. The work is substantially complete and he anticipates the product will be submitted for balloting in the December 2000 meetings. A formal ASTM number would be assigned after approval of method, now being called Standard Test Method for Concrete Poles.

The test considers testing of poles in a horizontal plane, as opposed to vertical, which can be complicated by use of winches, trucks and labor. "We specify how it's to be loaded, the loading increments, and what to measure as the pole starts cracking," Fouad says. "We specify loading cycles, deflection and movement for a typical section."

After balloting, the test method will go out for public comment. "By April or May of 2001 we will have received comments, which may result in changes to the method. We may either ballot again, or approve the method."

Two ASTM standard specifications have been promulgated, one for steady-cast concrete poles, and one for spun-cast poles.

- C1089-97 - Standard Specification for Spun Cast Prestressed Concrete Poles covers spun cast prestressed concrete poles for use as structural supports for street lights; traffic signals; transmission, distribution, and communication lines.

- C935-80-95 - Standard Specification for General Requirements for Prestressed Concrete Poles Statically Cast covers general requirements for prestressed concrete poles statically cast for use as structural supports for lights, distribution, transmission, and dead end poles.

"We update them as we go along," Fouad notes. "Last year we updated the spun-cast standard to reflect new technology, especially reinforcement details and manufacturing. Because these are prestressed structures, we made sure we had adequate details of reinforcement at the end of the pole, so it will not shatter on releasing the prestress."

Precast/Prestressed Concrete Institute recently published two documents pertaining to concrete poles: Guide Specification for Prestressed Concrete Poles, and Guide for the Design of Prestressed Concrete Poles.

"The design guide gives you all would need to know about the theory and design of spun concrete poles, but also chapters on handling and erection, including construction, foundations and use. The design specs provide ready-to-use specifications for a potential customer," authors report.

A new report on the handling and erection of concrete poles is forthcoming from the PCI committee. "Because weight is such an issue, we want to get rid of some misconceptions and show how you can properly handle, erect and otherwise construct a concrete pole," Fouad notes.

Centrifugal, or spun, casting lends the strength and slim profile prestressed, precast concrete needs to compete with products like steel, wood and fiberglass in the utility pole market.

"The advantages are that it creates a structure which is hollow and lighter-weight," says University of Alabama-Birmingham Professor Dr. Fouad H. Fouad, P.E. "With concrete, the big problem for the customer is the weight. The spun property gives you a hollow, thin-skinned, round shape which is preferred in the pole industry, because you have the same strength in all directions. Wherever you bend it, it has the same geometry, unlike a square or rectangle. The applications are vast."

With spun casting, high strength prestressing steel strands are wrapped with spiral wire, and are locked into tension plates at each end of the mold. Notes Newmark International, the leading producer in distribution poles: "The specially formulated high-strength concrete is placed into the bottom-half of the mold. The mold is bolted closed, the strand is prestressed, and then the mold is spun at a high rate," as much as 400 rpm.

The centrifugal force compresses the concrete against the walls of the mold, creating a finished pole that has a hollow center enclosed by the most dense, least permeable, strongest concrete man can make.

"Centrifugal casting compacts and increases the already substantial strength of our concrete," Newmark reports "Prestressing strands allow ultimate moment capacities far beyond the onset of cracking ... prestressed designs allow cracking capacities much higher than similar non-prestressed solutions."

The sheer force of the centrifugal spinning is used to promote Ameron concrete poles and counteract the image that concrete poles are fragile. "Ameron compacts the concrete by spinning at speeds to produce forces over 39 times the gravitational force of the earth," the firm says.

"This compaction fills air and water voids with cement paste which protects the pole from environmental, shipping and handling damage," Newmark says. "The concrete is so dense and strong that when we fired a 22-caliber ramset at point blank range at the concrete surface it was merely deflected with no damage to the pole."

"The ASTM standard (C1089, see related sidebar, page 33) requires a minimum 8,000 psi concrete, but typically the industry uses even more, often 10,000 psi," UAB's Dr. Fouad says. "The spinning further improves the strength of the concrete, making it denser and stronger."