Is Fiber Reinforced Concrete Approved and Specified by Government Agencies and Engineers?
May 28, 2013
The synthetic fiber reinforcement approved for use as temperature-shrinkage reinforcement in concrete is described in ASTM C1116, Section 4.1.3 and Note 2. The chemical base of the synthetic fiber resins that are compatible with a cement concrete is listed. International Code Council (ICC) has adopted a performance-based specification for Fiber Reinforced Concrete (FRC) as either plastic shrinkage crack reinforcement or temperature-shrinkage reinforcement or both. This performance-based specification was developed by one of ICC’s predecessors (International Conference of Building Officials) back in 1991.
The specification is ICC Engineering Services Acceptance Criteria ICC ES AC32 Section 3.1.1 lists the tests and performance number requirements for use as plastic shrinkage crack reinforcement, while Section 3.1.2 lists the test methods and performance number requirements for synthetic fiber reinforcement used as temperature-shrinkage reinforcement. ICC ES AC32 is the only performance-based specification in the world for Synthetic Fiber Reinforced Concrete.
The Fiber Reinforced Concrete Association (FRCA) is working with the ICC ES to enhance existing Acceptance Criteria for FRC used in International Residential Codes and International Building Codes as well as to produce new documents to reflect the growing list of applications and products. Including AC32 for microsynthetic fibers, mentioned above, there are two other Acceptance Criteria: AC208 for steel fibers and AC217 for cellulose fibers.
ICC has made one major change to its residential code. When wire mesh is used, ICC now requires the use of permanent supports to place the wire mesh in the upper half of the slab. This adjustment in the code benefits those using or wanting to use fibers. The permanent supports requirement increases material costs as well as labor costs while increasing the preparation time.
For the past few years, national and international organizations have been including FRC in their meeting agendas/programs. As early as 2011 the World of Concrete Conference included an FRCA seminar on FRC at the annual show.
FRCA was also asked by the National Ready Mixed Concrete Association (NRMCA) to develop a PowerPoint® program to help educate ready-mixed concrete company salespeople on the nuances of FRC and the value of FRC as a viable alternative to the old-generation wire mesh. These examples strongly suggest that the concrete industry recognizes FRC as adding physical and economic benefits to the concrete mix.
All of ABC Polymer’s concrete fiber reinforcement systems are designed and manufactured to meet the applicable consensus standards and building codes of the industry. Our FiberForce 650™ and PERFORMANCE PLUS DOT™ macrosynthetic fiber blend products have been accepted by a number of state Departments of Transportation (DOT) as well as specification and code applications. The company continues to obtain approvals from additional state transportation departments and to test the products at multiple dosage levels for commercial and industrial applications, with warehouse and industrial floors being the predominant focus.
Selection of wire mesh is based solely on empirical formulae. In comparing FRC with wire mesh, the FRC industry has worked very hard to develop meaningful data generated with recognized consensus test methods. Engineers generally recognize that a three-dimensional reinforcement system is far superior to a single layer of reinforcement that typically ends up residing on the subgrade.