Numerical Modelling of Reinforced Concrete Slabs under Blast Loads of Close-in Detonations Using the Lagrangian Approach

Abstract

Comparison between a typical and a simplified model for blast load-induced structural response A Abd-Elhamed and S Mahmoud Abstract. This paper includes an investigation for the deformations, including deflections and damage modes, which occur in reinforced concrete (RC) slabs when subjected to blast loads of explosions. The slab considered for the investigation is a one-way square RC slab with the dimensions of 1000 x 1000 x 40 mm, fixed supported at two opposite sides. It was subjected to close-in detonations of three different charge weights for a constant standoff distance. For the study, the slab was analysed using the numerical method by means of nonlinear finite element analysis. The slab was modelled as 3-D structural continuum using LS-DYNA software. For concrete modelling, two constitutive models were selected, namely the KCC and Winfrith concrete models. Blast loads were applied to the slab through the Lagrangian approach, and the blast command available in the software, namely LOAD_BLAST_ENHANCED, was selected for the application. The deflections and damage modes results obtained were compared to those from a previously published experiment. From the study, both the KCC and Winfrith concrete models effectively and satisfactorily estimated the actual slab maximum deflection. For damage modes, the KCC model appeared to be capable to capture satisfactorily the general damage mode including flexural cracks. However, the model could not capture the local shear mode at the middle of slab (spallation) because the Lagrangian approach does not simulate the interaction between the ambient air and the solid slab.

Experimental and Numerical Study of Non-Explosive Simulated Blast Loading on Reinforced Concrete Slabs

“…The ConWep algorithm is an empirical formula for calculating explosive loads. By inputting parameters, such as the type, mass, initiation method, distance, and height of the explosive, various aspects of the explosive load can be calculated [ 31 ]. The pressure–impulse criterion is used to evaluate the blast loading, and it is found that the blast loading closely matches the pressure and impulse of the impact loading.…”

Performance Assessment of Concrete and Steel Material Models in LS-DYNA for Enhanced Numerical Simulation, A State of the Art Review

“…Hence, the failed material act as a "load filter" for the remainder of the bar, which properties are determined by the EOS, the strength envelopes and the damage definition in the material models. Shuaib and Daoud demonstrated numerical modelling of reinforced concrete slabs under blast loads [95]. They selected KCC and Winfrith concrete models for concrete modelling.…”

Nghiên cứu áp lực sóng xung kích khi xảy ra nổ đồng thời

“…Smith và cs. [22,23]. Phương pháp CON-WEP còn được gọi là phương pháp Lagrangian thuần túy, trong đó tác động của vụ nổ được quy ra tải trọng đặt trực tiếp lên các bề mặt của kết cấu mà không thể hiện sự lan truyền sóng nổ.…”