Study On Human Lower Limb Injury In Coal Mine Underground Roadway Walking

The environment of underground roadway in coal mine is complex,and mechanized auxiliary transportation is difficult to be perfected in time.Walking is still the main way of passage in underground roadway.Generally,tracks,belts or other large equipment are arranged in the roadway,and the sidewalk space is limited.Moreover,the roadway surface under the underground is affected by mining,which often has ups and downs,which is not conducive to walking.Walking on complex road conditions for a long time is easy to cause fatigue injury of human lower limb joints.Workers in coal mine face the risk of occupational disease of lower limb joints injury.There are various types of underground roadways,and different roadways have different layout facilities and ways of passage.The vertical roadways mainly transport personnel by cage,while the inclined and horizontal roadways mainly transport personnel by cart and walk.Environmental factors such as temperature,ventilation,noise and lighting in underground roadway will aggravate human fatigue during walking and easily lead to lower limb joint injury.Underground workers must wear and carry safety equipment in accordance with regulations.Heavy clothing restricts the movement of human lower limb joints and reduces walking efficiency.Different types of underground work carry different equipment.The mechanical and electrical team carries 5.2kg,the gas detection team carries 7kg,and the ground survey team carries about 12.5kg of equipment,which increases the load on lower limb joints and increases the risk of damage.The walking cycle of human body can be divided into support phase and swing phase.According to the characteristics of human body,seven rigid body models consisting of trunk,thigh,calf and foot were established.Statics analysis of swing phase was conducted to obtain the torque formula of lower limb knee and ankle joint at different moments of swing phase.Combined with the man-machine environment characteristics of underground coal mine roadway,human walking models of incline roadway uphill,wearing restraint,walking of roadway unrolling road surface and walking with different loading modes were established respectively,and the human knee and ankle joint torque formula of incline roadway uphill walking was obtained.It was analyzed that wearing restraint would lead to the reduction of step length and increase the number of touching the ground,thus increasing the risk of joint injury.Undulating road surfaces and heavy loads can increase knee and ankle torque.By simulating the walking posture of the 5°,10°,15° and 20° inclinations,it is found that with the increase of the inclinations,the percentage of the population with task performance ability of the knee joint decreases from 98% to 25%,and the percentage of the population with task performance ability of the ankle joint decreases from 100% to 21%.The average energy consumption of the 10° inclinations is close to the upper limit of energy consumption.In the face of roadway undulation,the force on knee and ankle joints was significantly affected.57% and 22% of the population with task performance ability were on the left and right sloping ground,while 79% and 24%of the population with task performance ability were on the front and back sloping ground.Different loading ways will make the body joint stress is different,waist body load compared with portable and shoulder body load on the lower extremity less load.Through the man-machine environment analysis of coal mine roadway,combined with rigid body model analysis and JACK and Solid Works joint modeling and simulation,this thesis explores the influencing factors that are easy to lead to lower limb injury of coal mine roadway walkers,and provides suggestions for improving roadway layout,workers’ wearing and mine organization.There are 31 papers,16 tables and 83 references.