集中力作用下球形颗粒六角密排堆积体的传力研究

采用铝塑板技术和复写纸技术相结合,当球形颗粒堆积体在不同的六角密排情况下受集中力作用时,对堆积体底面力的分布情况进行了定量的实验研究.结果表明：在所有排列情形下都存在明显的拱效应,且在堆积体的每一水平层面上力的分布都具有120°对称性.证实了颗粒排列形式对力的传递有很大影响.发现在纯六角密排排列时,底部颗粒的受力最为平均,单个颗粒受力的最大值在所有排列中为最小.还发现了非主力链的“聚焦”现象.对实验结果做出了理论解释. 关键词： 颗粒介质 六角密排 力链

Force transmission in three-dimensional hexagonal-close-packed granular arrays submitted to a point load

In this article, the aluminium-plastic board and carbon paper technique are combined to investigate the contact force at bottom boundary of three-dimensional ordered granular arrays in response to a point load. Arching effects were observed with all arrays, and the force distribution markedly depends on the crystal structure and has a 120°-symmetry at every layer of the crystals, while the heterogeneity in force distribution in the pure hcp arrays is minimal of all the arrays. Non-main force chains were observed to have the “focalization" phenomena. These results can be explained by a force-transmission model.