聚丙烯纤维加固土融沉特性的离散元数值模拟研究

NUMERICAL SIMULATION OF THAW SUBSIDENCE CHARACTERISTICS OF POLYPROPYLENE FIBER REINFORCED SOIL BASED ON DISCRETE ELEMENT METHOD

针对掺入纤维对土体冻融特性的影响进行离散元数值模拟,首先自研了过程感知融化固结系统,基于融沉试验,提出了微观参数折减法模拟融化过程,分析了纤维掺量、纤维长度、土样高度的影响规律。结果表明:离散元方法可对融沉过程进行较为有效的模拟,并可得到最优纤维掺量,对于模拟工况,最优纤维掺量为0.1%;从融化压缩模量看,纤维长度与掺量为敏感影响因素,土样高度为次要因素;掺入纤维对土体强度与融沉特性的提升效果具有一致性。

In this paper,a discrete element numerical simulation was carried out to study the influence of doped fiber on the freeze-thaw characteristics of soil.Firstly,a process controlling thawing and consolidation system was developed.Based on the thaw-subsidence test,a microscopic parameter-reduction method was proposed to simulate the thaw process.Besides,the effects of fiber content,fiber length,and soil sample height on the thaw subsidence characteristics of fiber reinforced soil were analyzed.The results show that the proposed simulation method can preliminarily analyze the thaw subsidence process.The optimal fiber content can also be obtained by the discrete element method,and the optimal fiber content is 0.1%for the simulation cases.In term of the modulus of thawing compression,fiber length and fiber content are the most sensitive two factors.However,the sample height is not as sensitive as them.The improvement of fiber incorporation on soil strength and thaw subsidence characteristics is consistent.