Effects of occupant anthropometry on thoracolumbar injury risk in reclined postures during frontal collisions

doi:10.3969/j.issn.1674-8484.2026.01.005

Abstract

Abstract:

A full-vehicle frontal 100% overlap rigid barrier crash model was established to investigate the impact of anthropometric differences on occupant thoracic and thoracolumbar spine (T11—L5) injuries in reclined posture. The kinematic and injury responses of occupants in standard and reclined postures were compared, using the human finite element models THUMS (total human model for safety) of the 5th percentile female (5 F), 50th percentile male (50 M), and 95th percentile male (95 M). The results show that the reclined posture generally increases injury risk with injury patterns exhibiting significant body size specificity. Under the reclined posture, the 5 F exhibites the most pronounced thoracic injury risk, with lung pressure reaching 1 230 kPa and maximum principal rib strain reaching 4%. Injury risks for the 50 M and 95 M are concentrated in the thoracolumbar spine, the peak axial force and flexion moment at L2 of the 50 M exceeds the thresholds by 44% and 129%, respectively; the peak axial force at L1 of the 95 M exceeds the threshold by 38%, and the peak flexion moment at L5 exceeds the threshold by 111%. Moreover, the lateral bending moment of the thoracolumbar spine increases with larger body size.

Key words: frontal collision, total human model for safety (THUMS), reclined postures, anthropometric differences, injury risk

CLC Number:

U467.1+4

HUANG Zhishan, PAN Di, HAN Yong, XIAO Zonghan, LIU Hui, QIN Zhenyuan. Effects of occupant anthropometry on thoracolumbar injury risk in reclined postures during frontal collisions[J]. Journal of Automotive Safety and Energy, 2026, 17(1): 50-58.

Figures/Tables 13

References 29

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序号	角度	体型
工况1	25°	5 F
工况2		50 M
工况3		95 M
工况4	45°	5 F
工况5		50 M
工况6		95 M

序号	角度	体型
工况1	25°	5 F
工况2		50 M
工况3		95 M
工况4	45°	5 F
工况5		50 M
工况6		95 M

损伤部位	损伤评价指标	参考阈值
胸部	胸部3 ms合成加速度/g	60 ^[20]
	胸部压缩量/mm	高性能限值22 ^[21]
	胸部压缩量/mm	低性能限值50 ^[21]
	心脏压力/kPa	170 ^[22]
	肺部压力/kPa	16 ^[22]
	肋骨最大主应变(皮质骨)	2.4% ^[23]
胸腰椎	轴向力/kN	3.6 ^[24]
	前向弯矩/Nm	51 ^[25]
	横向弯矩/Nm	仅输出参考

损伤部位	损伤评价指标	参考阈值
胸部	胸部3 ms合成加速度/g	60 ^[20]
	胸部压缩量/mm	高性能限值22 ^[21]
	胸部压缩量/mm	低性能限值50 ^[21]
	心脏压力/kPa	170 ^[22]
	肺部压力/kPa	16 ^[22]
	肋骨最大主应变(皮质骨)	2.4% ^[23]
胸腰椎	轴向力/kN	3.6 ^[24]
	前向弯矩/Nm	51 ^[25]
	横向弯矩/Nm	仅输出参考

序号	胸部3 ms合成加速度/g	胸部压缩量/mm
工况1	29.8	25.2
工况2	40.3	26.7
工况3	38.0	30.1
工况4	31.2	28.3
工况5	28.4	33.2
工况6	41.8	33.7