本文基于常见的实验设备与自主开发的装置，研究将插入物从颗粒堆积中拔出时的最大拉力，探究颗粒物质奇特的力学行为. 具体而言，在精确控制颗粒堆积中插入物的角度、位置的基础上，改变体系堆积密度、颗粒粗糙程度、容器及插入物几何性质等重要参数，以研究它们对最大拉力的影响. 通过修正的Janssen模型，得到了拔出插入物所需最大拉力的理论表达式，从而探讨堆积密度和颗粒粗糙程度对理论模型中的唯象参数的影响. 将此实验研究继续发展推广，开发相关大学物理实验，能够帮助学生理解颗粒物质的力学现象，理解一系列软物质体系中的弹塑性力学行为.

In this paper, based on common experimental devices and self-made apparatus, the maximal force required for pulling out an object imbedded in a granular packing is studied to explore the peculiar mechanical behaviors of granular materials. Specifically, with an accurale control of the object's orientation and position, the packing fraction, particle roughness and geometric propertles of the object and container are changed to investigate their respective influences on the maximal force. Based on a modified Janssen model, an expression of maximal pulling force required is derived to understand how packing fraction and particle roughness affects the phenomenological parameters in the model. It is proposed that by further generalizing and developing this experiment, it would be able to help students understand the mechanical behaviors of granular materials as well as the elastoplastic properties of various soft matter systems.