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5/5/2013 | 3 MINUTE READ

Composite manhole covers pass load tests

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Fibrelite's composite covers pass AASHTO's load tests with flying colors.


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Fibrelite Composites Ltd.’s (Pawcatuck, Conn.) composite manhole covers have achieved another first by successfully passing load testing for both the AASHTO H20 and H25 highway load ratings for manhole covers. In testing performed at Lancaster University, Fibrelite’s 30-inch and 36-inch diameter composite covers were tested per the American load testing standards for manhole covers, grates and castings as set forth by the American Association of State Highway and Transportation Officials (AASHTO) M306-04 Standard Specification for Drainage, Sewer, Utility, and Related Castings.

The AASHTO M306-04 test specifications are used to predict how manhole covers, grates and castings will perform when installed in traffic lanes and where load bearing is a requirement. While the M306-04 specifications are specifically written for gray iron and aluminium castings, Fibrelite’s composite manhole covers and frames have been designed to meet or exceed the demanding requirements set forth by the standard. The M306-04 test requirements include 40,000-pound and 50,000-pound proof loading tests, respectively, for the H20 and H25 load tests. The requirements of the test include applying the proof loads to the cover and frame for a 1-minute period.  The tested products pass the test if following the application of the load there are no visible cracks to the cover or frame and there is no permanent deformation or deflection to the top of the cover in excess of 3.2 mm (1/8”). 

Fibrelite’s standard-duty FL760 (30-inch diameter) and FL90 (36-inch diameter) composite covers were subjected to the H20 40,000 pound proof load tests. Both of the standard duty covers successfully passed the test with minimal permanent deformation (less than the 1/8” allowed per the M306-4 standard) and no visible signs of cracking or damage. In addition, Fibrelite’s heavy duty FL760HD (30-inch diameter) and FL90HD (36-inch diameter) composite covers were subjected to the H25 50,000 pound proof load tests, and both successfully passed the test.The H20 and H25 test results are available upon request or by visiting Fibrelite’s website at http://www.fibrelite.com/i_reports.html.

For over 30 years, Fibrelite has been at the forefront in the design and development of composite products for the retail petroleum industry. Fibrelite introduced the lightweight composite manhole cover for use at gasoline service stations in the early 1980s and has continued to develop innovative product designs to meet the needs of a changing industry. Fibrelite currently offers the retail petroleum industry’s leading watertight composite covers, the industry’s only composite multiport cover and a wide range of molded fiberglass secondary containment and enclosures.

Fibrelite sees increased demand from all industries looking for alternatives to manhole and access covers made from materials such as cast iron, steel and concrete. This demand is due in large part to the numerous health and safety benefits of using lighter weight composite products.  And, composite manhole covers will not rust and are impervious to most chemicals, allowing for them to be used in corrosive environments found in sewers and certain manufacturing environments. Composite covers also have no resale value and municipalities and utilities experiencing the theft of metal covers are looking to composites as an alternative solution to metal.

“Inquiries are coming in daily and in increasing volume, from engineers and architects around the world.  Our products are now being specified for use in a wide range of facilities including water treatment plants, refineries, power stations, stadiums, port facilities and railway lines in addition to providing access to underground water, sewer and telecom services.  We now feature an extensive range of case studies on our website as an easy way to show the many applications and benefits of using composite access covers,” says Jim Goodman, Fibrelite’s president.

For larger openings or long trenches, Fibrelite offers a range of modular trench panels that can handle nearly any application. Fibrelite’s trench panels are lightweight for easy and safe manual removal, while providing the same load bearing capabilities as steel or concrete panels. The superior technical design of our composite trench panels also provide a durable, long lasting product that will not crumble, crack or corrode over time. With plants located in the United States, United Kingdom and Malaysia, Fibrelite products are sold in over 80 countries around the world.


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