Spall Fracture of an VNZh-90 Alloy under a Shock Wave Load

The subway station is easy to be attacked by terrorist bombings, and it will cause heavy casualties. In this paper, a comprehensive casualty assessment method for personnel in the subway structure was established based on the existing personnel injury model. The spatial distribution characteristics of the shock wave suffered by the personnel in the subway platform were obtained. Combined with the comprehensive casualty assessment method, the personnel casualty area for the explosions in the subway platform was divided. The results show that for the same explosive charge, the maximum positive phase impulse generated by the explosion at the edge of the platform is smallest. The “notch effect” for the stair exit will increase the shock wave load. When the explosive is exploded in the center of the platform, the smaller the explosive charge is, the more obvious the “notch effect” is. When the explosive charge reaches 40 kg, the personnel safety area is reduced to a certain extent behind the stair except for the explosion happening at the stair. Also, the higher the shield door is, the larger the safety area behind the stair is.

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Research on piezoelectric pressure sensor for shock wave load measurement

ISA Transactions ◽

10.1016/j.isatra.2020.05.018 ◽

2020 ◽

Vol 104 ◽

pp. 382-392 ◽

Cited By ~ 1

Author(s):

Yingjun Li ◽

Zhikang Yang ◽

Guicong Wang ◽

Cong Yang

Keyword(s):

Shock Wave ◽

Pressure Sensor ◽

Wave Load ◽

Load Measurement ◽

Piezoelectric Pressure Sensor

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Pressure Load on Rigid Structure Induced by Double Underwater Explosions

Volume 3: Structures, Safety and Reliability ◽

10.1115/omae2016-54158 ◽

2016 ◽

Author(s):

Rui Han ◽

Aman Zhang ◽

Shiping Wang

Keyword(s):

Shock Wave ◽

Underwater Explosion ◽

Time Difference ◽

Wave Load ◽

Underwater Explosions ◽

Rigid Structure ◽

Pressure Load ◽

Adjacent Structures ◽

Explosive Source ◽

Source Case

Underwater explosion is a severe threat to nearby ocean structures, such as underwater construction, floating vessels. The pressure load produced by underwater explosion of explosives consists of shock wave load and the explosion bubble pulsation pressure load. After the detonation, there will be a shock wave propagating radially outwards and it’s followed by a large oscillating bubble. The shock wave has the first damaging effect on adjacent structures. Then, the collapse and high-speed jet of oscillating bubbles will cause the second damage to structures. When there are double explosive sources near a rigid structure, the mutual superposition of shock waves and the interaction between two bubbles may improve the explosive damage. If the distance between one explosive source and the rigid structure is fixed, the damage force produced by double underwater explosions is related to many factors, like the detonation time difference and the distance between two explosive sources. At first, the pressure field in single explosive source case is numerically simulated by using the AUTODYN in this paper. Next, pressure fields of underwater explosion detonated by double sources at the same time and with time difference are calculated, respectively. The flow fields in double explosive sources case are compared with that in single explosive source case. The effect of the detonation time difference and the distance between explosive sources on the damage force is investigated and analysed in detail.

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The Fluid-Solid Interaction Dynamics between Underwater Explosion Bubble and Corrugated Sandwich Plate

Shock and Vibration ◽

10.1155/2016/6057437 ◽

2016 ◽

Vol 2016 ◽

pp. 1-21

Author(s):

Hao Wang ◽

Yuan Sheng Cheng ◽

Jun Liu ◽

Lin Gan

Keyword(s):

Shock Wave ◽

Failure Modes ◽

Sandwich Structures ◽

Numerical Models ◽

Near Field ◽

Three Dimensional ◽

Underwater Explosion ◽

Bubble Collapse ◽

Fe Model ◽

Wave Load

Lightweight sandwich structures with highly porous 2D cores or 3D (three-dimensional) periodic cores can effectively withstand underwater explosion load. In most of the previous studies of sandwich structure antiblast dynamics, the underwater explosion (UNDEX) bubble phase was neglected. As the UNDEX bubble load is one of the severest damage sources that may lead to structure large plastic deformation and crevasses failure, the failure mechanisms of sandwich structures might not be accurate if only shock wave is considered. In this paper, detailed 3D finite element (FE) numerical models of UNDEX bubble-LCSP (lightweight corrugated sandwich plates) interaction are developed by using MSC.Dytran. Upon the validated FE model, the bubble shape, impact pressure, and fluid field velocities for different stand-off distances are studied. Based on numerical results, the failure modes of LCSP and the whole damage process are obtained. It is demonstrated that the UNDEX bubble collapse jet local load plays a more significant role than the UNDEX shock wave load especially in near-field underwater explosion.

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Pressure Load Characteristics of Explosions in an Adjacent Chamber

Shock and Vibration ◽

10.1155/2021/3726306 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Chuan-hao Wang ◽

Shu-shan Wang ◽

Jing-xiao Zhang ◽

Feng Ma

Keyword(s):

Shock Wave ◽

Classical Model ◽

Low Frequency ◽

Reflected Shock Wave ◽

Main Chamber ◽

Wave Load ◽

Pressure Load ◽

Reflected Shock ◽

Internal Explosion ◽

Input Parameters

To learn more about dynamite explosions in confined spaces, we focused on the chamber adjacent to the main chamber, the main chamber being the location of the explosion. We investigated the characteristics of two damaging pressure loads: first reflected shock wave and quasistatic pressure. In this work, we analyzed the characteristics of the first reflected shock wave and the quasistatic pressure formed by the explosion of the chamber charge. Simulated chamber explosion experiments were carried out, where high-frequency piezoelectric sensors were used to measure the first reflected shock wave, and low-frequency piezo-resistive sensors were used to measure the quasistatic pressure. Valid and reasonable experimental data were obtained, and the experimental values of the pressure load were compared with those calculated from the classical model. The results showed that when the main chamber was partially damaged by the explosion load, the adjacent chambers were not subjected to the shock wave load, and the quasistatic pressure load was less than that in the main chamber. The presence of adjacent chambers did not affect the shock wave load in the main chamber. Using the mass of the explosive and the blast distance as input parameters, the internal explosion shock wave load parameters, including those in adjacent chambers, can be calculated. The presence of the adjacent chamber did not affect the theoretically calculated quasistatic overpressure peak in the main chamber. Using the mass of the explosive and the spatial volume of the chamber as input parameters, the quasistatic pressure load parameters of the internal explosion can be calculated, including those in the adjacent chambers.

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