森林灭火作业中水囊背负的脊柱生物力学研究

Spinal biomechanics of carrying a water bag in forest fire suppression tasks

为了评价森林灭火作业水囊背负时操作人员的脊柱受力,优化水囊背负的参数,建立了背负水囊与脊柱一体的生物力学模型,分析了背负水囊的质量、重心位置及人体背负姿势对第五腰椎与骶椎椎间盘L5/S受力的影响,并提出了有效减轻脊柱受力的水囊背负措施。结果表明:水囊的质量、重心位置和人体背负姿势均对L5/S内压有较大影响;为了保证脊柱受力安全,水囊背负质量应小于29kg;前屈姿势背负状态下,当人体上半身轴线与水平面夹角θ小于71°背负时,L5/S内压比直立姿势和θ大于71°的稍微前屈姿势背负时急剧增大,因此应尽量避免过度弯腰背负。

In order to evaluate the force of carrying a water bag in the tasks of forest fire suppression on the spines of operators and to optimize the parameters of water bag carriage,we established a biomechanical model of a water bag and spine.We analyzed the effects of weight,the position of the center of gravity and the posture when carrying a water bag on the force at the lumbar L5 /S joint（the inter-vertebral discs between the five lumbar and sacral vertebrae）.Finally,we propose measures for relieving this force on spines.The results indicate that weight,the position of the center of gravity and the posture when carrying a water bag each have a great effect on the force at L5 /S.A suitable weight of a water bag should be less than 29 kg to ensure the safety of spines.When carrying a water bag,the force at L5 /S with back flexion,while θ（the angle between the axes of the upper body and a horizontal plane） is less than 71°,is greater than the force with an upright posture and a slight back flexion while θ is more than 71°.A carrying posture of over flexion of the back should be avoided.