恒阻大变形锚索负泊松比结构效应实验研究

Materials with negative Poisson's ratio effect in rock shock resistance, shear and many other aspects including energy absorption than the traditional sense of the Poisson ratio of the material exhibits a more excellent performance. Therefore, in recent years for ordinary cable cannot resist the large deformation of soft rock and rock slope anchor breaking and other issues, a novel cable with large elongation and constant resistance also with negative Poisson's ratio effect has been researched and developed, and successfully applied to the mine disaster control field. However, in view of the negative Poisson's ratio of theoretical and experimental research is still blank for the anchor cable with large elongation and constant resistance. This project aims to use static stretching, infrared thermal imaging detection, discrete laser temperature measurement, the circumferential strain measurement and numerical simulation theories and methods to study radial and axial deformation law of constant resistance anchor cable with large elongation, and temperature effect, thermal infrared imaging effect, stress field evolution characteristics and energy absorption characteristics, revealing large deformation negative Poisson's ratio of anchor cable structure effect and energy absorption mechanism of constant resistance, to establish theoretical and experimental basis for constant resistance large deformation energy absorbing mechanism of anchor cable, has the important theory significance and practical value.

具有负泊松比效应的材料在抵抗岩体冲击、剪切和能量吸收等诸多方面比传统意义下的泊松比材料表现出更为优异的性能。因此，近些年针对普通锚索无法抵抗软岩大变形和岩体滑坡锚索拉断等问题，研发了具有负泊松比效应的恒阻大变形锚索，并成功应用于矿山灾害控制领域。但是，针对恒阻大变形锚索负泊松比效应的理论和试验研究尚属空白。本项目拟采用静力拉伸、红外热成像探测、离散激光测温、环向应变测量与数值模拟计算等理论和方法，研究恒阻大变形锚索的径向和轴向变形规律、温度效应、热红外成像效应、应力场演变特征及能量吸收特性，揭示恒阻大变形锚索负泊松比的结构效应和能量吸收机理，为恒阻大变形锚索的吸能机理建立理论和实验基础，具有重要的理论意义与实用价值。

本项目采用深部国家重点实验室（北京）自行研制的HWL-2000恒阻大变形锚索静力拉伸实验系统，对十余组恒阻大变形锚索进行静力拉伸实验。主要进行了以下几项工作：（1）利用自主研发的静力拉伸实验系统，对多组恒阻大变形锚索进行拉伸实验，通过对恒阻力值曲线的稳定状态分析发现，恒阻大变形锚索具有良好的恒阻效果；通过对不同加载速率条件下的恒阻力值对比分析后发现，恒阻大变形锚索随拉伸速率的增大而呈现“增阻”现象，即在现场工程中的体现为“岩体变形愈强，锚索的阻力也愈强”的重要控制作用；（2）对静力拉伸过程中锚索的力学曲线、轴向、径向、圆周方向变形量以及本体的温度变化曲线等数据的深入分析，揭示了恒阻大变形锚索具有负泊松比效应这一特殊力学特性；（3）采用激光测温系统和热红外成像系统对多组恒阻大变形锚索静力拉伸实验过程进行测量，对比本体的温度变化曲线和分析热红外成像后发现，恒阻大变形锚索具有吸能这一重要力学特性；（4）运用插值软件（Surfer）建立恒阻大变形锚索轴向和径向应变模型。按照恒阻大变形锚索静力拉伸试验相同的环境条件和工况条件，运用有限元分析软件（ANSYS）建立恒阻大变形锚索静力拉伸试验模型，开展一系列数值模拟计算，研究不同加载速率条件下恒阻大变形锚索在轴向和径向的变形规律。在基金委的支持下，通过资助人及其合作者的共同努力，本项目得以顺利完成，形成了23篇标注了基金号的已发表论文、专利8项等。