Numerical derivation of pressure–impulse diagrams for prediction of RC column damage to blast loads

• Published in: International journal of impact engineering Vol. 35; no. 11; pp. 1213 - 1227
• Main Authors: Shi, Yanchao, Hao, Hong, Li, Zhong-Xian
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.11.2008; Elsevier Science
• Subjects: Analytical formulae; Applied sciences; Building structure; Buildings. Public works; Construction (buildings and works); Damage criterion; Exact sciences and technology; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); Numerical derivation; Physics; Pressure–impulse diagrams; RC Column; Reinforced concrete structure; Solid mechanics; Structural and continuum mechanics; RC Column; Damage criterion; Numerical derivation; Analytical formulae; Pressure–impulse diagrams; Localized mode; Rupture; Displacement(deformation); Modeling; Reinforced concrete; Column; Concrete construction; Blast wave; Loadbearing capacity; Axial load; Mechanical protection; Pressure-impulse diagrams; Damaging
• ISSN: 0734-743X; 1879-3509
• DOI: 10.1016/j.ijimpeng.2007.09.001

Pressure–impulse ( P– I) diagrams are commonly used in the preliminary design or assessment of protective structures to establish safe response limits for given blast-loading scenarios. Current practice in generating the pressure–impulse diagram for structure components is primarily based on the simplified single degree of freedom (SDOF) model. The damage criterion is usually defined in terms of deformation or displacement response. Under blast loads, structures usually respond at their local modes, the equivalent SDOF system derived using the fundamental structure response mode might not be suitable. Moreover, structure is often damaged owing to brittle shear failure. In this case, the deformation-based damage criterion might not be able to give an accurate indication of local damage of a structural component. In this paper, a new damage criterion for RC column is defined based on the residual axial load-carrying capacity. A numerical method to generate pressure–impulse diagram for RC column is proposed. Parametric studies are carried out to investigate the effects of column dimension, concrete strength, longitudinal and transverse reinforcement ratio on the pressure–impulse diagram. Based on the numerical results, analytical formulae to predict the pressure–impulse diagram for RC column are derived. A case study shows that the proposed analytical formulae can be easily used to generate pressure–impulse diagram for RC columns accurately. The results are also compared with those obtained from the SDOF approach. It is shown that the proposed method gives better prediction of pressure–impulse diagram than the SDOF approach.