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Novel ionomer-laminated glass is popularly adopted as facades or structural elements due to its optical clarity and excellent load-bearing capacity. To better understand the behavior and failure mechanism of ionomer-laminated glass subjected to blast loading, a systematic study, including field blast tests, nonlinear dynamic numerical analysis, and pressure–impulse (P-I) analysis, was carried out. First, a series of full-scale field blast tests were conducted on 1,300 m×1,600 m×13.52 mm framed ionomer-laminated glass to investigate the precracking and postcracking responses as well as the failure mode of ionomer-laminated glass subjected to different explosions. The out-of-plane deflection fields over the panel surface were captured using the three-dimensional digital image correlation (3D-DIC) technique. A 3D solid finite-element (FE) model was developed using LS-DYNA for simulating the dynamic response of blast-loaded ionomer-laminated glass. The numerical results were compared with the test results for validation, which shows that the built model can reproduce the response of framed ionomer-laminated glass in both precracking and postcracking phases well. In addition, a P-I analysis was carried out for characterization of the influence of negative blast pressure over a wide range of blast threats. It was found that the negative blast pressure has a significant impact on the glass crack limit when the natural period of the laminated glass is in the same scale as the duration of the blast load, and an obvious influencing zone with the td/T ratio between 0.1 and 1 can be identified. The negative blast pressure has a similar influence on the interlayer rupture limit. Rebounding failure is highly likely to occur when the laminated glass is subjected to blast threats in the influencing zone. Neglecting the negative phase may result in overestimations of the blast resistance of ionomer-laminated glass at both damage levels. [ABSTRACT FROM AUTHOR]

High explosives are hazardous materials that are frequently used in industrial production which involves many safety and risk problems. To investigate the influence of the explosive charge shape on near-field blast loads (<1.0 m/kg1/3 in this study), 12 shots of field blast tests were carried out. The reflected overpressures of 1 kg TNT with different charge shapes at a distance of 800 mm and the incident overpressures at a distance of 1310 mm were measured and analyzed. The fireballs produced by the explosions were recorded by a high-speed camera and compared with each other. Results show that the fireball of a non-spatial symmetry explosive is non-uniformly distributed, which indicates the released energy is also non-uniform. The charge shape effect was further investigated using a verified numerical model. The experimental and numerical results show that the charge shape has a significant effect on the key parameters of blast loads such as the incident overpressure, the reflected overpressure, and the impulse. However, the influence of the charge shapes crumbled away with the increase of scaled distance. When the scaled distance is larger than 5.0 (6.0) m/kg1/3, the hemispherical (cylindrical) charge shape effect on the reflected peak overpressure and the impulse can be neglected. [ABSTRACT FROM AUTHOR]

Precast segmental columns have various advantages as compared to traditional cast-in-place monolithic columns. Numerous studies have been conducted to investigate the behavior of precast segmental columns under earthquake and impact loadings. However, there is limited research available on the dynamic response of precast segmental columns subjected to blast loads. In this study, the dynamic behaviors of precast segmental concrete-filled double-skin steel tube (PS-CFDST) columns under blast loading were examined. Field blast tests were conducted on three large-scale columns subjected to large equivalent explosions, and a typical failure pattern of fracture of post-tensioned (PT) tendons was observed in the test. A high-fidelity finite element model was developed to study the behavior of PS-CFDST columns under blast loading. The numerical model was validated against the test results and was then used to investigate the dynamic response, failure modes, and energy dissipation mechanism. It was found that the dynamic response of PS-CFDST columns could be divided into two phases, i.e., the shear deformation and bending deformation phases. In the shear deformation phase, the PS-CFDST column dissipates a significant amount of blast energy through the slippage between segments and absorbs most of the blast energy through the damage of the concrete and the outer steel tube. The self-centering capacity of PT tendons is primarily demonstrated in the bending deformation phase. The effects of modeling techniques for PT tendons and friction coefficient between segment surfaces were also investigated. An innovative sleeve connection of CFDST segments was proposed and its effect on improving blast performance of PS-CFDST columns was analyzed. • Field blast tests were conducted on three large-scale PS-CFDST columns subjected to large equivalent explosions. • High-fidelity finite element model was developed and validated against the test results. • The dynamic response, failure modes, and energy dissipation mechanism of PS-CFDST columns were investigated. • Effects of modeling approaches of PT tendons, surface interaction friction and sleeve connections were discussed. [ABSTRACT FROM AUTHOR]

This paper investigates effects of nanoscale materials and steel fibres on properties of ultra-high performance concrete (UHPC). Different types of steel fibres including twisted steel fibre (TF), waved steel fibre (WF), and micro steel fibre (MF) together with different kinds of nano materials including Nano-CaCO 3 , Nano-SiO 2 , Nano-TiO 2 and Nano-Al 2 O 3 are studied in the present research. Material compressive stress–strain relationships, strain energy absorption, the flexural strength and fracture energy absorption of UHPC with different nanoscale materials and steel fibres were compared and discussed. Laboratory static bending tests and field blast tests on structural components made of selected UHPC material composition were carried out, and the results highlighted the superior material ductility and blast resistant capacity of UHPC material developed in the present study. [ABSTRACT FROM AUTHOR]