摘要
包装堆垛存储是成品粮储藏的主要方式,堆垛倾斜倒塌是储藏过程中需关注的重要安全问题,其中包装粮摩擦特性是堆垛整体安全分析的关键因素。该文搭建了包装粮摩擦性能测试实验平台,进行了不同排列堆叠形式的包装粮层间摩擦特性测试与分析。研究表明:包装粮的变形是其层间摩擦特性的显著影响因素,层间接触摩擦力随变形的增大而增大,最终达到最大值后趋于平稳;包装粮的摩擦特性是由包装袋的层间接触摩擦性能、包装袋表面粮食颗粒间的咬合作用以及袋间相互嵌固效应共同影响的;多层堆叠的包装粮由于堆叠时侧面会向外轻微膨胀,而与相邻包装粮侧面形成挤压作用,层间接触等效摩擦系数相较于单面接触时更大;相同竖向荷载下,包装粮纵横十字交错排列(下部横向并列)相较于层叠无缝排列的等效摩擦系数增大41%~47%,四面接触挤压排列相较于双面接触挤压排列的等效摩擦系数增大38%~57%。该研究成果为包装粮堆垛倒塌机制研究提供了理论参考。
[Objective]Packaged grain stacking serves as the primary storage method for finished grain globally.However,stack inclination and collapse remain persistent safety hazards,threatening both economic sustainability and food security.Current industrial practices lack a systematic understanding of the interlayer friction mechanics governing stack stability,particularly under variable stacking geometries and long-term storage conditions.This study addresses this critical gap by quantitatively investigating the deformation-coupled friction behavior of packaged grain layers,aiming to establish a predictive framework for collapse risk assessment and provide actionable insights into the optimization of storage configurations.The urgency of this work is underscored by escalating global grain storage demands and the need to minimize postharvest losses estimated at 8%to 10%annually because of improper stacking practices.[Methods]A dedicated friction performance testing platform was developed to evaluate the interlayer friction dynamics in packaged grain stacks.The grain bag friction testing device was independently developed and mainly consisted of three systems:horizontal tension,vertical load,and measurement.The packaged grain was subjected to horizontal tension provided by a horizontal tensioning system,with a quantifiable vertical load applied to its upper part,and the horizontal tension and horizontal displacement of the packaged amount under different load conditions were obtained by the measurement system.The values obtained by the horizontal tension and horizontal displacement sensors were recorded,and the relationship curve between horizontal tension and horizontal displacement was plotted.Controlled experiments were conducted to analyze key variables,including stacking patterns(i.e.,laminated seamless,vertical–horizontal crisscross,and multisided contact arrangements),grain layer deformation,and interlayer interactions.Quantitative metrics,such as equivalent friction coefficients,were measured under incremental vertical loads to characterize friction evolution.[Results]The results showed that the deformation of packaged grain is a significant factor affecting the interlayer friction characteristics.The interlayer contact friction initially increases with the increase in deformation,subsequently reaches the maximum value,and finally tends to be stable.The friction characteristics of packaged grain are affected by the interlayer contact friction performance of the packaging bag,the bite effect between the grain particles on the surface of the packaging bag,and the mutual embedding effect between the bags.Because of the slight outward expansion of the side of the multilayer stacked packaged grain during stacking,the extrusion effect forms on the side of the adjacent packaged grain,and the equivalent friction coefficient of the interlayer contact is larger than that of the single-sided contact.Under the same vertical load,the equivalent friction coefficient of the vertical and horizontal crisscross arrangements(i.e.,the lower transverse juxtaposition)of the packaged grain is increased by 41%to 47%compared with the laminated seamless arrangement,and the equivalent friction coefficient of the four-sided contact extrusion arrangement is increased by 38%to 57%compared with the double-sided contact extrusion arrangement.[Conclusions]This study establishes a deformation-coupled friction model for packaged grain,revealing that optimized stacking geometries significantly enhance interlayer friction and collapse resistance.The quantified friction increments under crisscross and multisided contact arrangements provide actionable guidelines for designing stable grain stacks.These findings advance the mechanistic understanding of stack collapse and provide a scientific framework for improving grain storage safety standards.
作者
丁永刚
马贞诚
韩志强
许启铿
刘永超
张峰
王晨旭
DING Yonggang;MA Zhencheng;HAN Zhiqiang;XU Qikeng;LIU Yongchao;ZHANG Feng;WANG Chenxu(School of Civil Engineering,Henan University of Technology,Zhengzhou 450001,China;Zhongshan Grain Reserve Management Co.,Ltd.,Zhongshan 528400,China;Henan University of Technology Design and Research Institute Co.,Ltd.,Zhengzhou 450001,China)
出处
《实验技术与管理》
北大核心
2025年第5期90-96,共7页
Experimental Technology and Management
基金
河南省高等学校重点科研项目(25B560009)
企业合作科研项目(H2023TM417)。
关键词
包装堆垛存储
包装粮
摩擦性能测试平台
层间摩擦特性
排列堆叠形式
packaged grain stacking
packaging grain
friction performance test platform
interlayer friction characteristics
stacking patterns
