The LHT-1 rebound modulus tester was used to determine the compression density of paddy.The differential equations of density,stress and grain layer depth in hopper-bottom silo were built.Numerical method was used to obtain the relationship of density,pressure and depth and then the total weight of paddy was calculated by integration.Experimental results show that as the average vertical stress of paddy (00.495 ～ 245.892 kPa),the compression density of Huaidao No.5 paddy increased from 582.772 ～696.593 kg/m3 in the moisture range of 10.38％ ～ 18.30％ w.b.Model calculation results showed that in a silo with a cone hopper,density of paddy in cylinder of silo increased with the paddy depth,the density of paddy in cone hopper decreased with the increase of depth.The vertical stress acting on the paddy in cylinder part of silo increased with depth of paddy,and then decreased with the increase of depth in cone hopper.The lateral stress acting on the paddy in cylinder of silo increased with depth,then increased sharply in the junction of cylinder and cone hopper,the lateral stress of paddy in the cone hopper first increased slightly,and thcn decreased with the increase of depth of paddy heap.%采用LHT-1粮食回弹模量仪测定稻谷堆的压缩密度,建立带锥斗筒仓中稻谷堆的密度、应力与粮层深度关系的微分方程组,用数值方法计算带锥斗筒仓中稻谷密度、应力与粮层深度关系,由积分法计算出筒仓中稻谷的储藏总质量.试验结果表明,淮稻5号(含水率为10.38％ ～ 18.30％ w.b.)的密度随竖直应力(0.495 ～245.892 kPa)增大而增大(582.772 ～696.593 kg/m3).模型计算结果表明,在带锥斗筒仓的筒体部分,稻谷堆密度随着粮层深度的增加而增大;到锥斗部分,稻谷堆密度随着粮层深度的增加而逐渐减小.在带锥斗筒仓的筒体部分,稻谷堆的竖直应力随着粮层深度的增加而增大;在锥斗部分,稻谷堆的竖直应力则随着粮层深度的增加而减小.在带锥斗筒仓中的筒体部分,稻谷堆的侧向应力随着粮层深度的增大而增大;在筒体与锥斗结合处,稻谷堆的侧向应力突然增加;到了锥斗部分,稻谷堆的侧向应力随着粮层深度的增大先稍增大再逐渐减小.
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