FRP rebar: a revolution in concrete construction

DHAHRAN, July 11, 2018

Corrosion resistant fiber-reinforced polymer rebar is an ideal replacement of steel reinforcement for the aggressive environment in the region. At only one-quarter the weight of steel, it is easy to transport and construct.

Fiber-reinforced polymer (FRP) rebar has brought a concrete construction revolution that is in full alignment with Saudi Aramco efforts to promote nonmetallic solutions.

The corrosion resistant rebar is an ideal replacement of steel reinforcement for the aggressive environment in the region. And at only one-quarter the weight of steel, FRP rebar is easy to transport and construct.

Recently, the company successfully implemented FRP rebar in the foundations of a 400-meter long perimeter in one of its construction projects. The FRP rebar was much faster to construct than conventional steel rebar due to its lightweight and prefabricated nature.

In a parallel effort, Engineering Services, Project Management, and Procurement and Supply Chain Management are undertaking a major initiative to use FRP rebar in a 21-kilometer long storm water drainage channel in the Jazan Economic City project. Once constructed, it will be the largest project ever to be constructed using FRP rebar in the world.

A short history of FRP rebar

A few years back, Saudi Aramco collaborated with King Fahd University of Petroleum and Minerals, and King Saud University, on separate projects to evaluate the performance and durability of FRP rebar and FRP sheets under the typical local environmental conditions — specifically considering exposure to alkaline solutions (i.e., seawater and subkha), acidic solutions, thermal variation, the outdoors, and fire. The results of these studies confirmed the excellent potential for the use of these materials on new construction and for the strengthening or repair of existing structures.

Realizing the many benefits of FRP rebar in construction, Saudi Aramco has recently mandated FRP rebar be included in its engineering standards for noncritical structural members such as slab on grade, drainage channels, sidewalks, and pipe sleepers. Consequently, extensive efforts are being exerted to localize the manufacturing of the FRP rebar to meet the increasing demand. As a result, many international manufacturers have submitted plans to build manufacturing facilities in Kingdom.

What is FRP rebar?

FRP rebar simply consists of fibers (glass or carbon) embedded into a matrix (polymer). These rebars are manufactured by a process called pultrusion — a process that involves the pulling of the fibers through a liquid resin and then passing them through a heated steel die.

The resin, an oil-based product, acts as a “binder” to hold the fibers together and transfer the load to the fibers. The fibers provide the strength and other mechanical properties.

The final product is tested and qualified to verify mechanical properties, bonding with concrete, and durability.

Organizations such as the American Concrete Institute and the American Society of Testing Materials have developed design and construction criteria, as well as materials specifications for the manufacturing of FRP rebar. Saudi Aramco has adapted these standards to regulate FRP rebar qualities.