Numerical Study of Damage Modes and Damage Assessment of CFST Columns under Blast Loading

Abstract

Columns of frame structures are the key load-bearing components and the exterior columns are susceptible to attack in terrorist blasts. When subjected to blast loads, the columns would suffer a loss of bearing capacity to a certain extent due to the damage imparted, which may induce the collapse of them and even cause the progressive collapse of the whole structure. In this paper, the high-fidelity physics-based finite element program LS-DYNA was utilized to investigate the dynamic behavior and damage characteristics of the widely used concrete-filled steel tube (CFST) columns subjected to blast loads. The established numerical model was calibrated with test data in open literatures. Possible damage modes of CFST columns under blast loading were analyzed, and the damage criterion based on the residual axial load capacity of the columns was adopted to assess the damage degree. A parametric study was conducted to investigate the effects of critical parameters such as blast conditions and column details on the damage degree of CFST columns. Based on the numerical simulation data, an empirical equation was proposed to estimate the variation of columns damage degree with the various parameters.

Traffic Capacity Assessment of the Urban Elevated Bridge after Near-Field Explosion Based on the Response Surface Method

“…e corresponding damage indices D related to different explosion distances are calculated, respectively, and their relations are shown through the curves in Figure 9. e level classification of the damage indices D in the figure is quoted from [15]. As shown in Figure 9, the curve characteristics of the pier under the three types of car bombs are similar.…”

“…Based on the residual bearing capacity of the pier, the damage index D can be calculated, which is defined as [15] 150 mm…”

Tests of Inclined Concrete‐Filled Steel Tubular Stub Columns under Vertical Cyclic Loading

“…With the benefits of the CFST columns, using of the columns becomes widely adopted for multistorey building construction [2] and bridge piers [3]. In addition, the CFST columns also offer the advantage of preventing progressive collapse of buildings under blast loading [4]. However, there are some complications in the calculation of its capacity.…”

An improved nonlinear analytical approach to generate fragility curves of reinforced concrete columns subjected to blast loads

“…The column is one of the most important components in the reinforced concrete (RC) frame structures. Many researches were carried out to study the dynamic responses of RC structures subjected to blast loads including experiment (Islam and Yazdani, 2008; Slawson, 1984; Williamson et al, 2011a, 2011b), numerical simulation (Cofer et al, 2012; Tang and Hao, 2010; Wang et al, 2014; Zhang et al, 2016), and theory derivation (Qin et al, 2012). However, the parameter uncertainty was generally not considered in those studies.…”