The injury biomechanics of the pelvis in under-body blast conditions
File(s)
Author(s)
Pandelani, Thanyani Abson
Type
Thesis
Abstract
In recent conflicts, blast injury from landmines and improvised explosive devices (IEDs) has been the main mechanism of wounding and death. When a landmine or IED detonates under a vehicle, (an under-body blast), the seat acceleration rapidly transmits a high load to the pelvis of the occupants, resulting in torso and pelvic fracture. Pelvic fractures have high a mortality rate, yet their injury mechanism has been poorly researched.
This thesis seeks to advance the understanding of the pelvic injury mechanism of vehicle occupants and to quantify the loading environment at the vehicle seat due to under-body blast. This deeper understanding will lead to better protection and mitigation of injury and death.
An analysis of seat accelerations from live-fire vehicle experiments was conducted and the loading envelope was developed. Cadaveric tests were conducted using loading conditions within the envelope to explore the mechanism of pelvic injury.
In this thesis, a FE model of the pelvis was developed and compared with data from the cadaveric experiments. The material behaviour of the adipose tissue of the buttocks was deemed crucial to the biofidelity of the FE model, so experimental characterisation was conducted.
Tests were performed on cadaveric adipose tissue and an algorithm was developed and used to calculate the non-linear viscoelastic material properties of the human adipose tissue. The material properties will results in better response of the model and understanding of pelvic injuries in UBB events.
A validated 2D model of the pelvis was then used to quantify mitigation technologies. Three foams that can be applied in seats were tested virtually, and all showed variable levels of reduction of the load transmitted to the pelvis.
The findings of this thesis offer deeper insight into the mechanics of pelvic injuries. Researchers and vehicle designers can use the findings and the tools developed in this thesis to facilitate the development of vehicle and seat design for survivability.
This thesis seeks to advance the understanding of the pelvic injury mechanism of vehicle occupants and to quantify the loading environment at the vehicle seat due to under-body blast. This deeper understanding will lead to better protection and mitigation of injury and death.
An analysis of seat accelerations from live-fire vehicle experiments was conducted and the loading envelope was developed. Cadaveric tests were conducted using loading conditions within the envelope to explore the mechanism of pelvic injury.
In this thesis, a FE model of the pelvis was developed and compared with data from the cadaveric experiments. The material behaviour of the adipose tissue of the buttocks was deemed crucial to the biofidelity of the FE model, so experimental characterisation was conducted.
Tests were performed on cadaveric adipose tissue and an algorithm was developed and used to calculate the non-linear viscoelastic material properties of the human adipose tissue. The material properties will results in better response of the model and understanding of pelvic injuries in UBB events.
A validated 2D model of the pelvis was then used to quantify mitigation technologies. Three foams that can be applied in seats were tested virtually, and all showed variable levels of reduction of the load transmitted to the pelvis.
The findings of this thesis offer deeper insight into the mechanics of pelvic injuries. Researchers and vehicle designers can use the findings and the tools developed in this thesis to facilitate the development of vehicle and seat design for survivability.
Version
Open Access
Date Issued
2020-05
Date Awarded
2020-11
Copyright Statement
Creative Commons Attribution NonCommercial NoDerivatives Licence
Advisor
Masouros, Spyridon
Sponsor
Imperial College London
The Council for Scientific and Industrial Research
Publisher Department
Bioengineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)