This TechBrief discusses the potential use of fiber-reinforced polymer (FRP) bars in continuously reinforced concrete pavements (CRCP). Relative advantages and disadvantages of FRP bars are presented, and some specific considerations for the use of FRP bars in CRCP design and construction are described. This is followed by an overview of two recent experimental CRCP projects that have been constructed with FRP bars.

Concrete pavement design is currently centered on steel reinforcement. Whether that reinforcement be in the form of dowel bars, as is the case in jointed plain concrete pavement (JPCP), or in the form of continuous rebar reinforcement, continuously reinforced concrete pavement (CRCP). The use of steel in concrete pavements presents durability problems due to the corrodibility of steel. This study evaluates the use of polypropylene fibrillated, polypropylene macro, and carbon fiber fibers as primary reinforcement in concrete pavements for the Louisiana DOT. Results showed that fiber reinforcement can be used to improve both the fatigue and toughness performance of concrete. When post-cracked strength or toughness is the concern, concrete containing more fibers and fibers with higher tensile strength are desirable. Carbon fibers maintained greater load-carrying capacity at lower deflections than the steel fibers, which produced the greatest ductility. However, toughness and fatigue performance did not correlate for small deflections, suggesting that polypropylene macro fibers may be adequate for repeated, low stress loading. This study also found that when repeated low deflections are a concern, such as with pavements, there must be sufficient fibers across a crack to maintain a tight crack. Conversely, too many fibers prevent adequate consolidation and aggregate interlock, which negatively influences performance. When considering the pre-cracked fatigue performance of fiber reinforcement, the fibers needed to have sufficient length to reach across the crack and bond with the concrete, and that higher fiber dosages increase the fatigue performance of the concrete. The resulting pavement design, continuously fiber reinforced concrete pavement (CFRCP), will provide an alternative to JPCP and CRCP in highway pavement design that is not susceptible to durability problems associated with corrosion of the reinforcement.

Glass fiber reinforced polymer (GFRP) composite is applied widely in continuously reinforced concrete pavement (CRCP) because of its prominent advantages in properties and cost compared with conventional steel materials. This paper investigated influences of concrete strength, embedded depth, surface form, and diameter of bars on the GFRP-concrete bond performance by a series of pull-out tests. A finite element model was built to simulate the whole pull-out process. The test results showed that, within a certain range, rib depth has a positive effect on both slip control and stress improvement. Smaller rib spacing had a positive effect on controlling the slip displacement, but the diameter of bars and concrete strength had a negligible impact on both the bond strength and slip displacement. The developed finite element model (FEM) could provide similar results as the pull-out tests, and the model also demonstrated a distinct peak value in a shear stress cloud chart. Meanwhile, in order to analyze the effect of embedded depth on bond strength, a normal distribution model was utilized to fit the shear stress distribution. The analysis results retrieved from the normal distribution model, with an extreme small relative error less than 4 %, were more in line with the experimental results than the traditional average distribution model.

The use of fiber reinforced plastic (FRP) composites for prestressed and non-prestressed concrete reinforcement has developed into a technology with serious and substantial claims for the advancement of construction materials and methods. Research and development is now occurring worldwide. The 20 papers in this volume make a further contribution in advancing knowledge and acceptance of FRP composites for concrete reinforcement. The articles are divided into three parts. Part I introduces FRP reinforcement for concrete structures and describes general material properties and manufacturing meth.

Mechanics of Structures and Materials: Advancements and Challenges is a collection of peer-reviewed papers presented at the 24th Australasian Conference on the Mechanics of Structures and Materials (ACMSM24, Curtin University, Perth, Western Australia, 6-9 December 2016). The contributions from academics, researchers and practising engineers from Australasian, Asia-pacific region and around the world, cover a wide range of topics, including: • Structural mechanics • Computational mechanics • Reinforced and prestressed concrete structures • Steel structures • Composite structures • Civil engineering materials • Fire engineering • Coastal and offshore structures • Dynamic analysis of structures • Structural health monitoring and damage identification • Structural reliability analysis and design • Structural optimization • Fracture and damage mechanics • Soil mechanics and foundation engineering • Pavement materials and technology • Shock and impact loading • Earthquake loading • Traffic and other man-made loadings • Wave and wind loading • Thermal effects • Design codes Mechanics of Structures and Materials: Advancements and Challenges will be of interest to academics and professionals involved in Structural Engineering and Materials Science.