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1

Evaluation of Pressure Distribution in Buried Pipes with Liquid in the Explosion

Parviz M., Aminnejad B., Fiouz A. R.

Archives of Civil Engineering

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2019

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Vol. 65, nr 3

3--14

EN

In this Paper, a parametric study on pipes buried in soil was performed illustrating the results of blast loading. Effects of various parameters such as the physical properties of water, oil, gas, air, soil, pipes, and TNT have been investigated. The arbitrary Lagrangian-Eulerian (ALE) method was employed using LS-DYNA software. The maximum pressure in a buried pipe explosive was observed at an angle of about 0° to 45° and the minimum pressure occurred at an angle of about 45° to 90°. Therefore, all figures in this study illustrate that fluid pressure levels in buried pipes can help in their stabilization. In generally, by increasing the 1.23 times of liquid density under the explosion, the pressure levels in the soil decreased by 1.3 percent. The gas pressure has been increasing more than oil and water pipes 39.73 and 40.52 percent, respectively.

2

Resistance of columns

Eamon C., Alsendi A.

Builder

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2017

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R.21, nr 12

66--69

EN

A large strain, large displacement finite element model that allows element separation and failure is constructed and validated based on existing results of reinforced concrete columns subjected to blast loads. In this approach, concrete is represented with the Johnson-Holmquist-Cook model while a plastic-kinematic relationship describes steel behavior. The model is used to predict the capacity of typical reinforced concrete bridge columns to resist an assumed blast load scenario, where changes in concrete strength, steel reinforcement ratio, and axial force on the column are considered. The effectiveness of a method of column protection is investigated, where existing columns are wrapped with a relatively inexpensive steel fiber reinforced polymer (SFRP) jacket. It was found that the use of SFRP can significantly enhance the resistance of the columns.

3

3-D simulation of tunnel structures under blast loading

Buonsanti M., Leonardi G.

Archives of Civil and Mechanical Engineering

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2013

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Vol. 13, no. 1

128--134

EN

In this paper we want to study the behaviour of an underground structure subject to blast action. Other than the normal operating loads we considered the actions generated by a thermal gradient simulating the action of a fire load and by a pressure wave simulating an explosion. Initially the theoretical aspects of the problem were exanimated, and then a model was developed in numerical form and implemented through a finite element analysis. This modelling allows the simulation of a real scenario, e.g., railway tunnels with reinforced concrete structure that is subject to a fire generation and a subsequent explosion. The simulation involved aspects of thermal analysis, and therefore the structural problem was tackled analysing the tensions in the structure generated by the effect of temperature–pressure generated by the fire and by the overpressure generated by the blast. Only following this approach the most important factors influencing the dynamic response and damage of structure can be identified and the appropriate preventive measures can be designated.

4

Wpływy środowiskowe robót strzałowych

Modrzejewski S.

Górnictwo Odkrywkowe

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2005

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Vol. 47, nr 3

13-18

PL

Wprowadzenie nowych technologu wybuchowego urabiania skał zwięzłych w górnictwie odkrywkowym oraz postęp w dziedzinie produkcji ekologicznych materiałów wybuchowych i środków strzałowych, stwarzają możliwości poprawy efektywności robót strzałowych i ograniczania ich niekorzystnych oddziaływań środowiskowych. W artykule opisano pełne spektrum zagrożeń i negatywnych wpływów robót strzałowych na otoczenie kopalń. Przedstawiono ogólne zasady i formuły wyznaczania zasięgu szkodliwych wpływów wynikających ze stosowania materiałów wybuchowych oraz scharakteryzowano główne czynniki warunkujące ograniczanie zagrożeń.

EN

The introduction of new firm rock blasting technologies in open cast mining and the progress in the field of ecological blasting materials production and blasting resources create opportunities to improve efficiency of shot blasting works and limit their unfavorable influence on the environment. A full spectrum of threats and disadvantageous impact of shot blasting works on the surroundings of mine was characterized. General principles and formulas of determining the range of damaging influences, which result from utilizing blasting materials was presented and main factors, which condition the limitation of threats was characterized.

5

Prognozowanie wpływów robót strzałowych prowadzonych w górnictwie odkrywkowym na środowisko

Modrzejewski S.

Górnictwo Odkrywkowe

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2004

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R. 46, nr 5/6

35-42

PL

Przedstawiono główne czynniki zagrożenia środowiskowego od robót strzałowych. Scharakteryzowano poszczególne rodzaje oddziaływań oraz podano metody wyznaczania granic stref bezpieczeństwa ze szczególnym uwzględnieniem ochrony obiektów kubaturowych. Określono sposoby i wytyczne ograniczania zagrożeń od drgań sejsmicznych, rozrzutu i podmuchu w kontekście eliminacji szkód górniczych. Opracowano zależności propagacyjne umożliwiające zidentyfikowanie związków przyczyno-skutkowych w układzie działalność górnicza a uszkodzenia obiektów.

EN

The paper presents main risks for the environment caused by shot-blasting work. Specific types of impact were presented, and methods of determination of safe zones were outlined, with a special focus on protection of buildings. The author defined methods of and guidelines for limitation of risk caused by seismic vibrations, dispersion and blast in respect of elimination of mining damage. Propagation dependencies were determined in order to identify the cause-and-effect relations between the mining activity and damage f' buildings.