Biomechanical lumbar spine’s injury analysis of a seated occupant in a bus in effect of rollover crash simulation

Rollover accidents are one of the most serious injury forms. The harm caused by this type of injury has not been thoroughly studied. Prior research has focused on head and neck injuries and only investigated a 50th-percentile dummy; no one has examined the injuries suffered by women in collisions. In this study, the lumbar injuries of a 50th-percentile dummy without a seatbelt were compared to a dummy 5th in the same circumstance. Additionally, the lumbar injuries of a 5th-percentile dummy without a seatbelt were compared to those of a 5th-percentile dummy wearing one. The results of the study clearly show how important women’s safety is and how seat belts affect collisions. According to women’s physical characteristics, this study aids researchers in enhancing passive vehicle safety. According to the results, all three dummies experienced a high force along the y -axis, indicating a propensity to be thrown during a rollover. According to the study, under the same crash conditions, a 5th-percentile dummy suffered a 4.3% higher lumbar injury than a 50th-percentile dummy. This finding emphasizes how vulnerable females are to lower back injuries in crashes. In the belted condition, Compressive forces increased by 23.2% along the X -axis (0.586 kN → 0.722 kN) and by 72.9% along the Y -axis (0.641 kN → 1.108 kN), while compressive force along the Z -axis showed a slight 5.2% decrease (0.135 kN → 0.128 kN). Tensile forces along the Z -axis also decreased modestly (0.411 kN → 0.398 kN, −3.16%). This increase in force helps to keep the occupant in place, preventing ejection and enhancing safety. Compressive and tensile bending moments decrease by an average of 5%. The submarining analysis revealed no substantial deviation from the baseline results.