Dynamic Strength Properties of Concrete and Reinforcing Steel Subject to Extreme Loads

摘要

Understanding dynamic strength properties of concrete and reinforcing steel subject to blast, shock, or impact loads is required for numerical analysis and design of civilian and military structures. Generally, methods of the drop-weight impact test, split Hopkinson pressure bar test, and plate impact test have been used todetermine material response at high strain rate, while a servohydraulic testing machine is used to evaluate a static or quasi-static strain. Several organizations and researchers developed and proposed as a metric the dynamic increase factor (DIF) versus strain rate curves and/ or DIF formulations through experimental results, where the DIF is defined as the ratio of the dynamic stress to the static stress and is normally expressed as a function of strain rate. In this paper, DIF formulations are also proposed using the Unified Facilities Criteria (UFC) nonlinear DIF curve and based on the most recent database, which is needed for numerical analysis. Based on extensive literature reviews, this paper: 1) presents the definition of strain rate domains; 2) summarizes the features and limitations of experimental methods; and 3) systematically reviews the design curves and prediction models for concrete and reinforcing steel, along with the existing data.