水稻穴盘秧苗钵体力学特性试验研究

Experimental Study on Potting Characteristics of Rice Seedling in Hole Tray

以培杂泰丰杂交稻种为试验对象,在立体育秧温室培育穴盘秧苗。试验时苗龄28 d,钵体含水率35.76%~54.08%,仪器为TA-XT2i型质地分析仪。对穴盘苗钵体进行平板压缩、加卸载循环和蠕变试验研究,发现平板压缩变形约3.15 mm,抗压力随变形的变化趋势差异明显,压缩约4 mm,抗压力出现峰值上升变化陡点。当加载力为1、2、3、4和5 N,秧苗钵体平均蠕变量0.0055、0.0055、0.0056、0.0057和0.0059 mm。试验结果表明,钵体抗压力与变形呈非线性变动;平板压缩过程,钵体无明显屈服破坏点;苗钵体面对外界加卸载时表现较强塑变能力。选用Burgers模型能有效表征穴盘苗钵体压缩蠕变特性。分析多种稻种穴盘苗力学特性,结果发现不同穴盘苗钵体抗压力与变形关系遵循非线性曲线。该研究可为水稻移栽机设计优化提供理论参考。

Using Peiza Taifeng hybrid rice as experimental object,hole tray seedlings were cultivated in a three-dimensional seedling greenhouse.During experiment,seedling age was 28 d,moisture content of bowl was 35.76%to 54.08%.Instrument used was the TAXT2i texture analyzer.A study was conducted on plate compression,loading and unloading cycles,and creep tests of hole tray seedling bowl.It was found that compression deformation of plate was about 3.15 mm,and there was a significant difference in trend of pressure resistance with deformation;compression was about 4 mm,and peak value of pressure resistance increased sharply.When loading force was 1,2,3,4,and 5 N,average creep of seedling bowl was 0.0055,0.0055,0.0056,0.0057,and 0.0059 mm.Experimental results showed that pressure resistance and deformation of bowl body exhibited nonlinear changes;during compression process of flat plate,there was no obvious yield failure point on bowl body;seedling bowl exhibited strong plastic deformation ability when facing external loading and unloading.Burgers model ccould effectively characterize compressive creep characteristics of tray seedling bowl.Mechanical properties of various rice seed hole tray seedlings were analyzed.It was found that relationship between pressure resistance and deformation of different hole tray seedling bowl bodies followed a nonlinear curve.This study could provide theoretical reference for design optimization of rice transplanters.