Surfaces hold up well under heavy traffic: Wood, concrete, rubber and plastic offer distinct advantages to railroaders trying to keep crossing surfaces smooth - railroad grade-crossing surfaces - Industry Overview

Railway Track and Structures, June, 2001 by Kristi Matoba

Grade-crossing surfaces are something most of us encounter in everyday life, whether we drive, walk or cycle across them. Most people don't even notice them unless there is a rough ride.

With $4.6 million from the Federal Railroad Administration going to states with high-speed rail corridors to help eliminate hazards a public and private highway-rail grade crossings, grade-crossing technology will be in the public eye as never before. Below is a look at the various types of crossing surfaces currently available. Be sure to look at our "E&M Guide" and "Grade-crossing surface data sheets" for more information on grade-crossing products.

Concrete

CXT Incorporated has introduced two grade-crossing surface products over the past year: a prestressed panel that is more than 40 percent stronger than standard reinforced panels and a modular prestressed track slab.

"The benefits of a prestressed panel are that it is stronger structurally and uses a higher-strength concrete, which reduces the probability of surface cracking and spalling," said Dave Millard, manager of CXT's Rail Division. "Our PTS system is a prestressed modular crossing system that incorporates the benefits of an elastic fastening system for holding the rail and removable top panels for easy access to the rail. Track modulus transitions are also reduced by using discrete rail seats."

The company has also come out with a conformal tie pad that is placed between the bottom of the concrete crossing panel and top of the concrete tie. The conformal pad has features that help prevent the pad from moving off the tie.

"CXT can design and manufacture prestressed concrete crossings for virtually any type of crossing condition," said Millard. "CXT has produced special crossings for curves, special trackwork and devil strips. We also manufacture standard panels for nine-foot and 10-foot wood or concrete ties at 18-, 19-3/16-, and 19-1/2-inch tie spacing."

He has noticed that the market continues to use more and more concrete grade crossings, and believes that it is due to their low cost, ease of use, and durability.

"CXT is proud to lead the market with the development of the pretensioned, prestressed panel, which is a substantially-stronger panel at a very competitive price," added Millard. "CXT sells crossing panels to a wide range of business customers, from Class 1 railroads to contractors and private industry. The market is soft right now, but we are continuing to grow our business."

CXT received ISO 9001 quality registration in 2000 and, at present, is the only ISO 9001 certified concrete-grade-crossing producer.

On the flangeway front, CXT has developed and patented an innovative preattached flangeway filler made of Santoprene that is durable, chemical resistant, and has excellent electrical resistance properties, Millard notes.

"CXT's preattached flangeway filler makes the panel very quick, safe, and easy to install," said Millard.

Century Group Inc. recently began manufacturing a grade crossing that consists of concrete gauge panel with standard elastomeric flangeway filler. On the field side, a rubber flangeway insert is stalled next to the rail and hot-mix asphalt is used in lieu of a concrete field panel.

"The crossing system is being used on a limited basis by some Class 1s and shortlines in the northeastern part of the United States on an experimental basis," said Rusty Vincent, president/ceo of Century's Railroad Products Division.

Century also provides lagtype and lagless grade-crossing panel designs in various lengths ranging from eight-foot to 10-foot, depending upon the customer's specifications. The company manufactures grade crossings for 90-pound rail and larger.

"We specialize in custom grade crossings to fit turnouts, diamond crossings, curves, hi-rail access crossings and pedestrian crossings," said Vincent.

"Century started 2001 with a large backlog of projects and business has been steady. We expect orders to slowly increase through the year as business and industry regains confidence in the economy," he said.

The company also has a new attached flangeway filler system that has a greater electrical resistance and is much more durable than were previous elastomeric fillers.

KSA offers three concrete crossing panel lengths: 8-foot, 0-inch, 11-foot, 2-inch and 12-foot, 0-inch, depending on whether the installation is on wood or concrete crossties. KSA gauge panels have four locking "feet," two on each side of the panel. These "feet" project both down and out from the gauge panel base and are designed to lock each panel into place, preventing both lateral and longitudinal panel creep under heavy traffic conditions.

"One critical area, which in the past has been overlooked by crossing end users, is mandatory ASTM testing of the concrete by suppliers," said Dale Beachy, KSA's manager specialty products. "Externally, all concrete looks the same. ASTM testing of both raw materials and the hardened concrete by certified independent laboratories is the only accurate way to determine the concrete's internal quality. Test results must be monitored on a regular basis by the end user. KSA's standard policy has always been to subject not only raw materials but also the hardened concrete to a wide variety of ASTM documented tests. ASTM C-666 -- Procedure "A," rapid freezing and thawing of concrete in water, is one example of our testing procedures."