Title: Structural Behavior of TL-4 Recycled Tire Chip and Fiber Reinforced Concrete Single Slope Barriers

Author(s): Grace Darling, Stephan A. Durham, and Mi G. Chorzepa

Publication: Symposium Paper

Volume: 347

Issue:

Appears on pages(s): 176-190

Keywords: Single Slope Barrier, Rubberized Concrete, Fiber Reinforced Concrete (FRC), Dynamic Impact, Recycled Tire Chips, Steel Fibers, Concrete Median Barrier (CMB), MASH Testing

DOI: 10.14359/51732664

Date: 3/1/2021

Abstract:

Concrete median barriers (CMB) are installed to decrease the overall severity of traffic accidents by producing higher vehicle decelerations. In 2016, an update to the AASHTO Manual for Assessing Safety Hardware (MASH) saw a 58% increase in impact severity of test level 4 (TL-4) impact conditions when compared to the NCHRP Report 350 testing criteria. This study investigates the use of fiber-reinforced rubberized CMBs in dissipating the impact energy to improve driver safety involved in crashed vehicles. Two full-scale barrier prototypes with shear keys were constructed and tested under impact conditions in a laboratory setting. Compared to the Georgia Department of Transportation specified single-slope barrier, the fiber-reinforced rubberized concrete mixture, a design with 20% replacement of the coarse aggregate by volume with recycled rubber tire chips and a 1.0% steel fiber addition, was evaluated based on its performance in toughness, energy absorption capacity, and its recoverable deformation. It is concluded that the TC20ST1 barrier performed as well as the control barrier at the impact load of 150.0 kips (667.2 kN), with neither barrier experiencing any visible damage.