Title: Damage Accumulation Comparison of Fiber-Reinforced Concrete Using Repeated Drop Impact Testing

Author(s): Andrew D. Sorensen, Robert J. Thomas, Ryan Langford and Abdullah Al-Sarfin

Publication: Symposium Paper

Volume: 347

Issue:

Appears on pages(s): 127-137

Keywords: drop-weight impact, damage prediction, fiber reinforced concrete, impact testing standards

DOI: 10.14359/51732661

Date: 3/1/2021

Abstract:

The impact resistance of concrete is becoming an increasingly important component of insuring the durability and resilience of critical civil engineering infrastructure. Design engineers are not currently able to use impact resistance as a performance-based specification in concrete due to a lack of a reliable standardized impact test for concrete. An improved method of the ACI standard, ACI 544.2R-89 Measurement of Properties of Fiber Reinforced Concrete, is developed that provides a resistance curve as a function of impact energy and number of blows (N) to failure. The curve provides information about the life cycle (N) under repeated sub-critical impact events and an estimate of the critical impact energy (where N=1), whereas the previous method provided only a relative value. The generated impact-fatigue curve provides useful information about damage accumulation under repeated impact events and the effectiveness of the fiber-reinforcement. In this paper, the improved method is demonstrated for three fiber types: steel, copolymer polypropylene, and a monofilament polypropylene. Additionally, the analytical solution for the specimen geometry is given as well as the theoretical considerations behind the development of the impact-life curve. The use of a specimen geometry provides a path to generalize the test results to full-scale structures.