Change search
Refine search result
1 - 3 of 3
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard-cite-them-right
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Elofsson, Mats
    et al.
    Försvarets Materielverk.
    Johnsson, Fredrik
    Swedish Defence University, Department of Military Studies, Military-Technology Division.
    Forsman, Björn
    SSPA.
    Liwång, Hans
    Swedish Defence University, Department of Military Studies, Military-Technology Division.
    Riskanalys för att fatta bättre beslut2016In: Tidskrift i sjöväsendet, ISSN 0040-6945, Vol. 2, p. 130-141Article in journal (Other academic)
  • 2.
    Johnsson, Fredrik
    et al.
    Swedish Defence University, Department of Military Studies, Military-Technology Division.
    Vretblad, Bengt
    Swedish Defence University, Department of Military Studies, Military-Technology Division.
    Full-scale experiments to determine shaped charge penetration in sandbag constructions from long standoff distances2015In: 16th ISIEMS International Symposium on the Interaction of the Effects of Munitions with Structures, 2015Conference paper (Refereed)
    Abstract [en]

    Protective measures must often be established during explosive ordnance disposal (EOD) operations to reduce the effects of unexploded ordnance (UXO). Adequate models for the design of protective constructions against the jet from shaped charge ammunition are lacking. Two conditions are unique for EOD operations on shaped charges: constructions built from sandbags and long standoff distances. For these conditions, verified test data are very limited.

     

    To study these conditions, full-scale experiments have been conducted at the Swedish EOD and Demining Centre (SWEDEC) with the objective to generate data for the development of a useful tool for EOD operations. Three series of five shots using a 107 mm warhead have been fired against both sandbag and homogenous sand/gravel targets, at standoff distances from 10 to 100 calibers.

     

    The result indicates that the hydrodynamic penetration theory, based on the Bernoulli equation, is not suitable for these target materials and these standoff distances. The actual penetration was more than twice what was expected from calculations based on this theory. Furthermore, the penetration was found to be significantly smaller when the sand/gravel was packed in sandbags – a result in contradiction to the same theory.

     

    Standoff curves which also take into account if the target material is packed in sandbags or not have been developed. The general shape of these curves is different from what is characteristic for materials such as metals and concrete. Increasing standoff decreases penetration only marginally.

     

    The jet is fully fragmented into smaller segments when it hits the target, but still has good penetration capability in these target materials. This phenomenon is related to the cut-off velocity, the lowest jet velocity that gives a contribution to the penetration, which is considerably lower than for more resistant target materials. Combining the influence of the cut-off velocity with the hydrodynamic penetration theory is used in the explanatory model in the paper.

     

    The experiments also demonstrated that the target material surrounding the jet moved forward, resulting in a growing penetration channel after the jet was fully consumed. This is related to phase three penetration. The contribution to the total penetration is considerable and gives a plausible explanation as to why sandbags give better protection.

     

    The results have been used to develop a new model for the design of protective measures against jet penetration. The military utility for EOD operations has been the main criteria during all development phases. The final result is a simple tool that can be used under field conditions. Approximately one year after the first experiments, the result has been implemented in regulations and training for EOD personnel in the Swedish Armed Forces.

  • 3.
    Johnsson, Fredrik
    et al.
    Swedish Defence University, Department of Military Studies, Military-Technology Division.
    Vretblad, Bengt
    Swedish Defence University, Department of Military Studies, Military-Technology Division.
    Sivertun, Åke
    Swedish Defence University, Department of Military Studies, Military-Technology Division.
    Shaped Charge Calculation Models for Explosive Ordnance Disposal Operations2012In: Journal of Military Studies, ISSN 1799-3350, Vol. 3, no 1, p. 1-24Article in journal (Refereed)
    Abstract [en]

    The clearance of unexploded ordnance (UXO) and other explosive remnants of war (ERW) containing shaped charge warheads poses a particular technical hazard to consider for explosive ordnance disposal (EOD) personnel. The wide use of light anti-tank weapons, such as rocket propelled grenades and the scattering of sub-munitions in different conflict areas have made the clearance of shaped charge ammunition a frequent task. However, unlike other hazards, for shaped charges, EOD personnel lack adequate means for the establishment of the maximum hazardous area and for the design of measures for hazard confinement against the shaped charge effect.

    In this article two different models are suggested, which together give guidance for protective measures during clearance of shaped charge ammunition. The development of these models is based on their military utility, by consideration of the limited information availability, the short time frames, the working methods and the technology level that are characteristic for EOD operations. The two suggested models are developed further into a complete set of design rules for protective measures, giving a versatile tool to replace today´s rough estimates and guesswork, in these safety-related decisions.

1 - 3 of 3
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard-cite-them-right
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf