皮蛋抗压试验及弹性模量和泊松比的测定

Compression test and elastic modulus and Poisson′s ratio of preserved egg

针对皮蛋外形为非标准椭球,难以采用定义方法求其弹性模量的问题,采用美国ASABE提出的弹性模量(E)求解方法和泊松比(μ)测定方法,阐述皮蛋的球度、外观尺寸、曲率半径等基本物理量的求解和系数λ与cosα的数学关系计算原理,利用TMS-PRO食品物性分析仪和小位移传感器为主要测量仪器分别对皮蛋横向和纵向进行压缩试验,获得其不同方向的应力应变曲线,分析计算得出皮蛋抗载弹性模量:中间受压为3.204 MPa,两端受压为3.666 MPa;泊松比:中间受压为0.155 4,两端受压为0.383 0。

In view of the non-standard ellipsoidal shape of the preserved eggs, it is difficult to adopt the defining methods to determine the elastic modulus. This research adopts the elastic modulus （E） proposed by ASABE solving method and Poisson＇s ratio （μ） determination method to describe the calculation principle based on the mathematical relation between the coefficient A of the basic physical quantities of the preserved egg such as the sphericity, appearance of size,curvature radius and and cosine theta. TMS-PRO food property analyzer and small displacement transducer are used as the main measuring instruments to carry out transverse and longitudinal compression experiments on the preserved egg re- spectively to obtain the stress strain curve of different directions. The load-resistance elastic module of the preserved egg is as follows; the intermediate pressure is 3. 204 MPa, and the pressure on both ends is 3. 666 MPa; Poisson＇s ratio; the intermediate pressure is 0. 155 4, ans the pressure on both ends is 0. 383 0.