A Unified Performance-Based Blast-Resistant Design Approach for RC Beams/Columns

The deliberate and unintentional explosions pose a significant risk to vital political and economic infrastructures. The current study focuses on analyzing the model and design method for reinforced concrete beams and columns subjected to blast loads, taking into account both the local and global reactions of the members. In this chapter, the damage levels of blast loaded RC beams/columns are classified from a local response perspective. This classification is based on a total of 119 field explosion tests, which categorize the damage levels as no damage, spalling, and breach. Through these tests, the critical scaled distance that distinguishes between local and global responses of RC members is experimentally determined to be 0.78 m/kg1/3. A logarithmic scaled thickness against logarithmic scaled distance design chart is displayed to analyze local reactions in the field explosion test. Furthermore, in terms of global reactions, a refined SDOF model is developed that takes into account the direct shear, flexural-shear, and flexural responses of RC elements. This model comprehensively considers the nonuniform distribution of blast load, the effect of strain rate, the P-Delta effect, the compressive arching effect, and the rigid body rotation of supports. In addition, the validity of the proposed SDOF model is confirmed by seven sets of explosion tests conducted on RC beams and columns. These tests involve both simply-supported and fixed-end limits and evaluate the direct shear, flexural-shear, and flexural responses. Ultimately, a comprehensive performance-based blast-resistant design technique is put forward, serving as the basis for an autonomously created code called Tongji-RC-Blast. This code functions as a dependable and efficient tool for assessing and designing blast-resistant structures, catering to the needs of protective engineers and designers.