有缝隙颗粒堆积体中应力传递规律的实验研究

散体颗粒堆积体在自然界和实际工程应用中普遍存在,具有许多复杂奇异的特性,如应力链、崩塌、非线性波等.对有缝隙颗粒堆积体进行焦散线实验研究,与无缝隙情形进行对比分析,发现:缝隙的存在对应力的传递有较强的阻碍作用,使颗粒堆内部应力的传递范围明显缩小,其分布满足六次多项式规律,而不是无缝隙情形的抛物线规律;有缝隙颗粒堆内部的应力分布符合高斯分布函数,各层应力的最大值是无缝隙情形的2～3倍.

Stress Distributions in Granular Packs with Gaps

Understanding the mechanical properties of granular materials is important for applications in nature and the civil industry.The granular packs show some perplexing and fancy properties,such as stress chains,dilapidation and nonlinear wave etc.In this article,the caustics method is used to investigate the distributions of contact forces inside a granular pack with gaps submitted to a compressive load.Our experimental results demonstrate that the gaps inside the granular packs play an important role in the transmission and distributions of the strain,the strain transmission boundary in the granular packs are subjected to a six-degree polynomial expression,and the maximum value of the strains in the granular packs with gaps is double or three times to the strain value at the same height in the packs without gaps.