深松铲扰动下天然草地复合土层失效特性的试验研究

Experimental study on failure characteristics of natural grassland composite soil structure under subsoiling operation

为研究深松铲类耕作部件作用下天然草地扰动失效过程,采用草地耕作试验台搭载不同类型和具有不同结构参数的深松铲,在不同作业深度下,进行草地扰动失效试验,对草地土层失效过程、扰动情况、翻垡率、扰动系数、蓬松度,以及耕作部件的作业阻力和沟形面积比阻进行对比分析。试验结果表明:利用深松铲可以打破天然草地形成的“地表干草+植物根茎+土壤”的“夹层式”复合土层结构,对草地土层造成扰动,但其作业效果受作业深度、结构参数以及“夹层式”复合土层结构的影响。深松铲作业后产生的地表翻垡率为5.67%~12.25%,扰动系数为63%~74%,蓬松度为38%~49%。综合所有的扰动失效特性参数,在所试验的深松铲耕作部件中,双翼倾角为150°的双翼形深松铲在草地深松作业时对草地地表扰动和土壤翻垡情况影响较小,对土壤的扰动系数较高,作业效果最佳。

The aim of this study was to study the natural grassland disturbance failure process under the action of subsoiler tillage tools.Field tests were conducted under different operating depths by using a tillage test bench carrying different types of subsoilers with different wing inclination angles.The failure process of the grassland soil layer,disturbance,soil overturning rate,soil disturbance coefficient,soil bulkiness,working resistance of tillage tools,and specific draft forces were compared and analyzed.The results showed that:The subsoiler tillage tools could break the composite soil structure of grassland and cause disturbance to the grassland soil layer,but their operations were affected by the working depth,structural parameters,and the special composite soil layer structure.After the subsoiling,the surface soil overturning rate was 5.67%-12.25%,the disturbance coefficient was 63%-74%,and the bulkiness was 38%-49%.Based on all the disturbance failure characteristic parameters,among the tillage tools tested,the subsoiling shovel with a double-wing inclination angle of 150° has little effect on the disturbance and soil overturn of grassland surface and high disturbance coefficient on soil,and therefor achieved the best working effect.