PREVENTION OF SOIL COMPACTION ON HARD-PAN DUE TO CYCLIC WHEEL LOADS

防止由于循环轮载荷而导致硬盘上的土壤压实

基本信息

批准号：
10460112
负责人：
HASHIGUCHI Koichi
金额：
$ 5.76万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10460112/
关键词：
Wheel performance testing device Online-measurement of soil deformation Cyclic compaction of soil Tractive efficiency Extended subloading surface model Soil stress measurement system Elastoplastic finite element analysis 有限要素解析圃場耕盤土

项目摘要

The evil influence on soils for crop growing has been brought out by the cyclic compaction by farm wheels, whilst the sizes of farm machinery are increasing year and year. In this research the soil compaction phenomenon due to the wheel traveling is studied experimentally using the soil bin equipment for the precise measurement of wheel traveling performance and theoretically developing the elastoplastic finite element program. The main results obtained in this article are as follows :1) Soil particles traces an ellipsoidal locus by the passage of wheel. The locus locates backward relative to wheel as the slippage increases.2) The size of locus decreases with the number of wheel traveling. Its rate of decrease is more remarkable as the slippage increases.3) The compaction of soil is remarkable near the soil surface. It decreases proportionally to the depth until 60 mm depth and then decreases rapidly. Bedsides, it decreases exponentially with the number of wheel traveling.4) The amplitude of shear strain increases and thus soil compaction becomes remarkable with the slippage. In other words, the soil compaction is influenced remarkably by the dilatancy due to the shear deformation.5) The highest tractive efficiency and the smallest soil compaction is realized at the 5-10% slippage in the case of the rigid wheel traveling on sandy soil.6) The finite element program was developed incorporating the subloading surface model. The soil deformation beneath the wheel is predicted qualitatively by the program.

农机车轮的循环压实对农作物生长的土壤造成了不良影响，而农业机械的规模逐年增大。本研究利用土仓设备对车轮行驶引起的土壤压实现象进行了实验研究，以精确测量车轮行驶性能，并从理论上开发了弹塑性有限元程序。本文取得的主要结果如下： 1）土壤颗粒通过车轮的通过，追踪出椭球轨迹。随着滑移量的增加，轨迹相对于车轮向后移动。2）轨迹的大小随着车轮行驶次数的增加而减小。随着滑移量的增加，其减小幅度更加显着。3）土体表层附近的压实作用明显。它与深度成比例减小，直到 60 毫米深度，然后迅速减小。在床边，随着轮子行驶次数的增加，它呈指数下降。4)剪应变的幅度增加，因此土壤压实随着滑移而变得显着。换句话说，土壤压实度受到剪切变形引起的剪胀的显着影响。 5) 刚轮在沙土上行驶时，滑移量为 5-10% 时，牵引效率最高，土壤压实度最小。 .6) 有限元程序的开发结合了次加载表面模型。该程序可以定性地预测车轮下方的土壤变形。