Role of cross-diagonal reinforcements in lieu of seismic confining stirrups in the performance enhancement of square RC columns carrying axial load subjected to close-range explosive loading

Abstract

Exposure of building infrastructures to accidental or intentional blasts is an extreme load condition that may cause irreparable damage leading to the collapse of buildings. Columns being principal elements are the most important for the stability and safety of the buildings under accidental explosions and subversive blast events and therefore attract the attention of structural engineers and researchers. Some recent examples are the Beirut seaport explosion (August 2020), the explosion at an ammunition warehouse in Ryazan City of Russia (October 2020), the gas explosion in China’s Hubei Province (June 2021), a blast at a chemical factory on the outskirts of Bangkok (July 2021), and the explosion on a container ship docked at Dubai’s Jebel Ali Port (July 2021). In the crises like ongoing conflict between Russia and Ukraine, the enhanced response of the principal components of a structure may save the life of the building users by limiting severe damage to the structure. In this study, three experimentally tested 3000-mm-long normal strength concrete columns, 300mm x 300mm, provided with (i) conventional reinforcement, (ii) seismic reinforcements over top and bottom confining regions (600 mm), and (iii) seismic reinforcement over confining and mid-height regions, carrying an axial working load of 950 kN available in the literature, are modeled in the ABAQUS 2020 code and are subjected to 82 kg TNT close-range explosive load at a scaled distance 1.0 m/kg1/3 using the software’s explicit module. In addition to this, one column with seismic reinforcement over its entire length has been considered and modeled. The concrete damage plasticity model is explored for nonlinear elastic and inelastic behaviors, degradation of stiffness, and loading rate effect on concrete. Following the validation of the numerical models, the seismic reinforcements of the columns have been replaced by the cross-diagonal reinforcements between the conventional stirrups with the same axial load. Blast performance of the columns with the seismic reinforcements and with replaced diagonal reinforcements is critically examined and discussed. The results show that the application of cross-diagonal reinforcements as a replacement for the seismic reinforcements enhances the blast resistance of the reinforced concrete column significantly by reducing the damage and displacement.

Ultra high performance concrete and C-FRP tension Re-bars: A unique combinations of materials for slabs subjected to low-velocity drop impact loading

“…In Refs. (Sadraie et al, 2019;, Shariq et al, 2022a;Tahzeeb et al, 2022a;Tahzeeb et al, 2022b;Tahzeeb et al, 2022c;Ul Ain et al, 2021;Ul Ain et al, 2022;Anas et al, 2022i;Anas et al, 2022j;Ahmadi et al, 2022;Shariq et al, 2022b;Shariq et al, 2022c;Shariq et al, 2022d;Anas et al, 2022k;Anas and Alam, 2022d;Anas et al, 2022m;Anas et al, 2022n;Shariq et al, 2022e;Anas et al, 2022o;Anas et al, 2022p;Shariq et al, 2022f;Anas and Alam, 2022e;Shariq et al, 2022g;Anas et al, 2022q;Shariq et al, 2022h;Anas et al, 2022r) employ the Concrete Damage Plasticity (CDP) model, which takes the strain-rate effect into account. A damage plasticity model can be used to describe the mechanical behavior of concrete.…”

“…There is a thorough explanation of the CDP in Ref. (Yılmaz et al, 2018;Anas et al, 2022a;Anas et al, 2022b;Anas et al, 2022d;Ahmadi et al, 2021;Anas et al, 2020a;Anas et al, 2020b;Anas et al, 2020c;Anas and Ansari, 2021;Anas et al, 2021a;Anas et al, 2021b;Anas et al, 2021c;Anas et al, 2021d;Anas et al, 2021e;Anas et al, 2021f;Anas and Alam, 2022b;Anas and Alam, 2022c;Anas et al, 2022e;Anas et al, 2022f;Anas et al, 2022g;Anas et al, 2022h;Anas et al, 2021g;, Frontiers in Materials frontiersin.org 2022a; Tahzeeb et al, 2022a;Tahzeeb et al, 2022b;Tahzeeb et al, 2022c;Ul Ain et al, 2021;Ul Ain et al, 1007). The analysis makes use of previous research information on NSC, UHPC, and SFR-UHPC concrete found in References (Anas et al, 2022a;Anas et al, 2022b;Anas et al, 2022d).…”

Numerical Modeling of Steel Column for its Response to Large Explosive Loading using CEL-FEM Approach

“…To address the strain-rate effect in steel material, the present study utilizes the Johnson-Cook (J-C) approach in ABAQUS. For in-depth information on this model, refer to the works of [6][7][8][9].…”

“…The paramount objective is to guarantee the protection of these structures by meticulously designing them with adequate fortitude and flexibility to endure the expected level of threat in accordance with designated criteria [4][5][6][7]. Columns play a crucial role in the construction industry [8][9][10][11][12]. If any of these elements were to malfunction on a localized level, it could result in the complete failure of the entire framework, especially if the construction does not have redundant load pathways [13][14][15][16][17][18][19].…”

Effect of thermal cycles on the engineering properties and durability of sustainable fibrous high-strength concrete

“…Furthermore, fibres are being used as discrete three-dimensional reinforcement to address the limitations of ordinary cement concrete and as a replacement for ultra-high-performance concrete (Bajaber and Hakeem, 2021). Fibre-reinforced concrete incorporates fibre into its mix to improve load resistance (Anas et al, 2022a;Anas et al, 2022b). Various types of fibre-reinforced concrete have been created, each with distinct and important advantages because of its various advantages, including good ductility, tensile strength, and fatigue resistance.…”